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STUDIES
IN MEDIEVAL SCIENCE
AND
PHILOSOPHY, LOGIC
Published under the auspices of the CENTER FOR MEDIEVAL AND RENAISSANCE STUDIES University of California, Los Angeles
Publications of the CENTER FOR MEDIEVAL A N D RENAISSANCE STUDIES, UCLA 1. Jeffrey Burton Russell: Dissent and Reform in the Early Middle Ages 2. C. D. O'Malley: Leonardo's Legacy 3. Richard H. Rouse: Serial Bibliographies for Medieval Studies 4. Speros Vryonis, Jr.: The Decline of Medieval Hellenism in Asia Minor and the Process of Islamization from the Eleventh through the Fifteenth Century 5. Stanley Chodorow: Christian Political Theory and Church Politics in the Mid-Twelfth Century 6. Joseph J. Duggan: The Song of Roland 7. Ernest A. Moody: Studies in Medieval Philosophy, Science, and Logic
Studies in Medieval Philosophy, Science, and Logic Collected Papers 1933-1969 ERNEST A. MOODY
UNIVERSITY OF CALIFORNIA PRESS BERKELEY
LOS ANGELES
1975
LONDON
University of California Press Berkeley and Los Angeles, California University of California Press, Ltd. London, England ISBN: 0-520-02668-J Library of Congress Catalog Card Number: 73-91661 Copyright © 1975 by The Regents of the University of California Printed in the United States of America
Contents Foreword
vii
Preface
ix
William of Auvergne and His Treatise De Anima (1933)
1
John Buridan on the Habitability of the Earth (1941)
111
Ockham, Buridan, and Nicholas of Autrecourt (1947)
127
Ockham and Aegidius of Rome (1949)-
161
Laws of Motion in Medieval Physics (1951)
189
Galileo and Avempace: The Dynamics of the Leaning Tower Experiment (1951)
203
Empiricism and Metaphysics in Medieval Philosophy (1958)
287
The Age of Analysis (1963)
305
A Quodlibetal Question of Robert Holkot, O. P., on the Problem of the Objects of Knowledge and of Belief (1964)
321
Buridan and a Dilemma of Nominalism (1965)
353
The Medieval Contribution to Logic (1966)
371
Galileo and His Precursors (1966)
393
William of Ockham (1967)
409
Jean Buridan (1969)
441
Foreword
Ernest Moody is not only a profound scholar and a lively companion: he is a totally independent spirit, capable of charting his own course toward new adventures as few of us are. During the financial boom and crash of the '20s and early '30s he worked on Wall Street until the Great Depression persuaded him to abandon the service of Mammon for the consolation of philosophy. Having become sufficiently consoled to achieve a professorship at Columbia University, he resigned his chair and spent the better part of a decade operating an isolated cattle ranch in Texas, some sixty-five miles from the Mexican border. Once a week he drove to town to get the mail, buy supplies, and have a beer with the boys in the local saloon. But the ranch house had a library that collected no dust, and at last he was ready for another change, and crossed Jordan to the Canaan of Southern California. His changes of life-style, and the diversity of the sorts of people with whom he has lived and worked, may help to explain the comprehensiveness of his learning. N o American medievalist has done more, both b y editing difficult texts and b y their interpretation, to expand our understanding of late medieval logic. But his Truth and Consequence in Medieval Logic—written during his Texan period— which won the Haskins Medal is unique-, it translates the discursive logical Latin of the fourteenth century into the formulaic expression of twentieth-century symbolic logic. It is accessible to only a trace element in the guild of medievalists, but has immensely increased respect for the prowess of medieval logicians among their present-day successors. Moreover, Ernest Moody has fused his probings of logic with remarkable work in the history of medieval mathematical mechanics. W h o else combines so successfully the history of logic with that of science in this period? vii
Foreword, More important is his capacity for synthesis and new insights. His work is fundamental to our undemanding of the way in which the thinkers of Frankish lands assimilated, evaluated, and built upon the great mass of Greek and Arabic philosophy that came into Latin from the eleventh century onward. His masterly essay "Empiricism and Metaphysics in Medieval Philosophy," reprinted in this volume, is revolutionary for intellectual history. In Moody's words, if the later fourteenth century "has seemed to the historians of philosophy an age of decline, to the historians of science and logic it has seemed an age of rebirth and advance.... For better or worse, it gave a new character and direction to all later philosophy, of which we have not yet seen the end." T o gather Ernest Moody's scattered articles, and one major unpublished piece, into a single volume, is a great service to international scholarship for which the University of California Press should be thanked. Lynn White, jr.
viii
Preface
The essays gathered together in this volume were written over a period of thirty-seven years, embracing the whole span of my career as a scholar and teacher. The first study, on William of Auvergne, was written in 1933 as a thesis for the Master of Arts degree at Columbia University. Although it has been on deposit in the Columbia Library for the past four decades, it has not hitherto appeared in print. The last of the essays, on Jean Buridan, was written for The Dictionary of Scientific Biography and appeared in the year of my retirement from active academic life at UCLA in 1969. The essays are ordered chronologically so that they provide, along with the books I wrote during those years, a fairly complete record of the development of my interests in the fields covered. The preparation of this volume has given me occasion to reread the studies contained in it and to reflect not only on their content and on the circumstances under which they were written but also on the remarkable flowering of medieval studies that took place during the period in which I was working in the field. Although medieval art and vernacular literature had some devotees in the early years of this century, it was not until after the First World War that the study of medieval thought in the areas of philosophy, science, and legal and political theory began to come into its own. My four years as an undergraduate at Williams College, from 1920 to 1924, came before this revival of medieval studies, and though I majored in philosophy and studied its history as then taught, the twelve centuries between Augustine and Galileo were dismissed as unworthy of serious attention. It was not until 1932, eight years after my graduation from Williams, that I decided to pursue a life of scholarship and enrolled ix
Preface as a graduate student in philosophy at Columbia University. By then it had become possible to engage in research in medieval philosophy in a few universities such as Harvard and Columbia, and I made the personal decision to specialize in this field. Several circumstances influenced my decision to concentrate on medieval philosophy. One was the fact that I had acquired competence in Latin as a student at Trinity School in New York, at a time when four years of high school Latin were required for college entrance. It made sense to choose a field in which I could utilize this skill, which was no longer commonplace. Another factor was the presence at Columbia of a young assistant professor, Richard McKeon, who was competent to guide research in this area. Although his own doctoral research, completed in 1928, had been on Spinoza, he had studied medieval philosophy with Etienne Gilson at Paris and was one of a handful of American scholars acquainted with the subject. At Columbia there were also sufficient library resources for such research, matched only by those of Harvard. Finally, it was apparent that the medieval field offered ample opportunity for original research, with many first-rate thinkers whose works had scarcely been studied by any modern scholars. The rebirth of medieval studies, especially in philosophy and science, had begun only a few years before, and mostly in Europe. In America the pioneer works of Charles H. Haskins, Medieval Science and The Renaissance of the Twelth Century, were published in 1927, while the first volume of Lynn Thorndike's History of Magic and Experimental Science appeared in 1929. The Medieval Academy of America had been organized at Harvard in 1925, and shortly after, in Toronto, the Institute of Medieval Studies, sponsored by Etienne Gilson and St. Michael's College, was started. It was a good time to get in on the ground floor. The first essay in this volume, on William of Auvergne and his treatise De anima, was my initial venture into the field of medieval philosophy, carried out during the academic year 1932-1933 and submitted as a thesis for the M. A. degree that I received in 1933. In rereading the study I am conscious of the somewhat limited background from which I worked at that time. The scholarly material then available was nearly all of nineteenth-century vintage done in France and Germany, and my own critical standards reflected the ways in which philosophical problems had been formulated and discussed by American philosophers of the first two decades of this x
Preface century. Nevertheless, I am not ashamed of this first work of mine, even though, if writing it today, I would use other forms of expression and do more to relate the material to its historical and philosophical contexts. In comparing my study with the third volume of A. Masnovo's Da Guglielmo (TAuvergne a S, Tommaso d'Aquino, published in 1945, which deals primarily with the same material as my essay, I am pleased to find that his analysis is in rather close accord with that of my study. Although I had originally intended to continue with William of Auvergne for my doctoral dissertation, I became interested in William of Ockham and decided to switch my research to him. What attracted me to Ockham, in the first instance, was the bad publicity given to him by the Thomists and particularly by Gilson, who portrayed him as a diabolical genius who tore down the beautiful edifice of scholastic philosophy and theology erected by Saint Thomas Aquinas. Since it was natural for me to side with the underdog, I felt the urge to find out what Ockham had to say. In the academic year 1933-1934 I worked on this project with McKeon's help, after which he left Columbia to go to Chicago. But by the end of 1934 I had completed my book, The Logic of William of Ockham, and was fortunate enough to find a publisher, F. J. Sheed, who brought it out in the autumn of 1935. In those days publication was required for the award of the Ph.D., so it was not until 1936 that I received the degree. The first stage of my plan for an academic career was thus completed, but the next step, of finding a position in a university, was not easily accomplished in those years of the Great Depression. Like William of Ockham, I was in danger of becoming a "venerable inceptor," waiting for a license to teach. My book on Ockham received many favorable reviews, including one by Gerald B. Phelan, president of the Institute of Medieval Studies at Toronto. He urged me to come there and held out the promise of finding a place for me in the Institute if I would do so. I made several visits in the autumn of 1936 and took part in Gilson's seminar. But I did not wish to move to Toronto, and decided to wait my time at home while pursuing further research in the medieval field. The fourteenth century fascinated me, and when I came across the studies of late medieval physics which had been done just before the First World War by Pierre Duhem, I sent for photostats of the writings of Jean Buridan, including most of those extant in early editions as well as some writings found only in manuscript xi
Preface versions. With the help of Capelli's manual and of Steffens' facsimiles, 1 taught myself to read the medieval scripts and devoted most of 1938 to preparation of an editio princeps of Buridan's Quaestiones super libros Aristotelis De caelo et mundo. This was published by the Mediaeval Academy of America in 1942. Meanwhile I wrote the article "John Buridan on the Habitability of the Earth," which appears as the second essay in this volume (reprinted, by permission, from 'Speculum,' XVI [1941], 415). It contained my edited text of one of Buridan's Questions, on an interesting problem of geology, with an analysis of its content. In 1939 I received an appointment as Lecturer in Philosophy at Columbia University, and was asked to give two courses for graduate students. I offered courses and seminars in areas of medieval philosophy and on Aristotle and Saint Augustine. After a four year interruption during the Second World War, I returned to Columbia as Associate in Philosophy, later becoming Associate Professor. My most productive years commenced at this time, stimulated by contacts with colleagues, students, and other scholars of the area. At Columbia Paul Kristeller and I worked together on several projects, including a joint seminar on manuscript reading and editing. One of our students was Thomas Merton, who later gained fame as a poet, writer, and Trappist monk. In the areas of contemporary logic and philosophy of science I had common interests with Ernest Nagel, who gave me the benefit of his knowledge and critical acumen. A meeting ground for scholars in the New York area concerned with historical studies in philosophy and science was the Renaissance Seminar sponsored by J. H. Randall, Jr. This group met each month at Columbia, where research papers were read and discussed. Being pressed to make a contribution to the group, I worked up the material in my study, "Galileo and Avempace: The Mechanics of the Leaning Tower Experiment," which appears as the sixth essay in this volume (reprinted, by permission, from the Journal of History of Ideas, XII, 2 [April 1951], 163-193; XII, 3 [June 1951], 375-422). Early in 1946 I made the acquaintance of Philotheus Bijehner, O.F.M., who had organized the Franciscan Institute at St. Bonaventure College. He was eager to enlist my aid in promoting the study of William of Ockham and asked me to write something for publication in Franciscan Studies, which he edited. The result was the third essay of this volume, Ockham, Buridan and Nicholas of Autrecourt Xll
Preface (reprinted, by permission, from Franciscan Studies, 7, 2 [June 1947], 113-146). The fourth essay, Ockham and Aegidius of Rome (reprinted, by permission, from Franciscan Studies, 9, 4 [December 1949], 417-442), was also written at Boehner's request for a special issue of Franciscan Studies devoted to Ockham, whose death in 1349 was being commemorated in 1949. At that time Boehner also persuaded me to undertake the task of preparing a critical edition of Ockham's commentary on Porphyry's Praedicabilia, as a contribution to the projected edition of Ockham's philosophical works which was being sponsored by the Franciscan Institute. I worked on this task for some years, completing it just before Boehner's untimely death in 1955. Because of his death, publication was delayed for ten years, when the edition finally appeared as a Franciscan Institute publication. The essay on "Ockham, Buridan and Nicholas of Autrecourt" was one of my better efforts, from the point of view of construction and literary merit. On receiving it, Father Boehner said that it read like a detective story. It did however contain two errors that should be brought to the reader's attention. In presenting the view of Bernard of Arezzo concerning intuitive cognition, as quoted by Nicholas of Autrecourt, I stated that this was Ockham's doctrine and that Bernard of Arezzo should be regarded as a defender of Ockham. But I would now have to modify this because of Bernard's statement that "Clear intuitive cognition is that by which we judge a thing to exist, whether it exists or does not exist." This does not correspond accurately to Ockham's position, according to which a clear intuitive cognition is that by which we can evidently know that a thing exists, if it exists, or that it does not exist, if it does not exist. Whether Bernard's statement was a slip, and not actually intended to differ from Ockham's view, cannot be known with certainty; but the difference, as it stands, is important. T o what extent this may affect my assumption that Bernard was a leader or member of a pro-Ockham faction in the university, attacked by Nicholas of Autrecourt, is uncertain. But it does make it harder to establish a clear cut division between defenders and critics of Ockham on the basis of the letters of Nicholas of Autrecourt. However, the part of my essay dealing with the content of the decree of 1340, concerning the question of literal interpretation of texts, seems to me perfectly sound. The second error in my study, of less significance, consists in my use of a statement taken from the 1497 edition of Holkot's works as testimony to Ockham's position that a xiii
Preface real science is of propositions whose terms stand for things that exist independently. The printed edition of Holkot, in actuality, ascribed to Ockham a position that belonged to Walter of Chatton, so that my use of this quotation was inappropriate. I discovered this mistake in 1962, when I studied a manuscript of Holkot dealing with the problem of the objects of knowledge and wrote the article that appears as the ninth essay in this volume. I would still defend the main thesis of my 1946 study, that the decree of 1340 was not directed against the teachings of Ockham, as well as the general treatment I gave of Ockham's empiricism and the rationalism of Nicholas of Autrecourt, in relation to the issue of skepticism. The remaining essays written while I was at Columbia, numbered four to six in this volume, represent research in medieval physics and its relation to Galileo and seventeenth century science. The article on "Ockham and Aegidius of Rome" used material uncovered in this research, but it was mainly intended to show that Ockham's attack on those who treated quantity as a real accident distinct from substance was not directed against Saint Thomas as most historians had supposed, but was aimed specifically at Giles of Rome. The article "Laws of Motion in Medieval Physics" (reprinted, by permission, from The Scientific Monthly, 72 [January 1951], 18-23) summarized the main contributions of the fourteenth century to the science of mechanics. Most of my effort in the area of medieval physics, however, was given over to the writing of the long study on "Galileo and Avempace." This study contains some controversial views on the relationship between Platonism and Aristotelianism in the development of early modern science, and in particular it challenges the contentions of Alexandre Koyre and of Ernst Cassirer on this issue. The views I expressed in this study have in turn been questioned by others, notably by the late Anneliese Maier in her book, Zimschen Philosophie und Mechanik (Rome 1958). I am not ready to make any retractions, however. My last two years at Columbia, from 1949 to 1951, were largely given over to work on two books. One of these, The Medieval Science of Weights (Scientia de ponderibus), grew out of a project I set up for students in the seminar on manuscript reading and editing which Kristeller and I gave as a joint project. I used a manuscript of the De ratione ponderis of Jordanus de Nemore as material for transcription by our students. They managed to get the first book done, and this xiv
Preface was enough to get me started on the task of editing all the known medieval treatises on statics from the available manuscript sources. After constituting the texts and providing English translations and introductions for each treatise, I then added detailed commentaries in which the content of each work was analyzed in its scientific and mathematical aspect. When I had finished I showed the manuscript to my friend Marshall Clagett, who was then at the University of Wisconsin, and he asked if he might join me as a collaborator by contributing similar texts, translations, and commentaries for works on the subject by Thabit ibn Qurra and by Blasius of Parma. I had known Clagett since 1940, when I had been a member of his examining committee for the doctorate in history. I was happy to have him as coauthor of the book and also to have him arrange for its publication by the University of Wisconsin Press as the first of their series of Publications in Medieval Science. This book seems to have established a literary form for works of this sort, which has been followed in the books dealing with medieval science written since then by Clagett and his able pupils, as well as by one of my Columbia students who contributed a volume to the Wisconsin series. The one effort, which put a strain on my modest training in physics and mathematics, was sufficient for me, especially since I had let myself get involved in another project which put its own strain on my very modest training in mathematical logic. There had been established at Amsterdam, Holland, under international sponsorship, a project for publishing studies in logic and the foundations of mathematics, with L. E. J. Brouwer, E. W. Beth, and A. Heyting as general editors. The publishers of the series asked me to contribute a volume on medieval logic, and this I agreed to do. The result was my book, Truth and Consequence in Medieval Logic, which was published in 1953 and well received. What I attempted to do in this book was to give an interpretation, in formulations that would be intelligible to a modern logician, of the medieval theories of truth conditions and of logical consequence. I used symbolic devices, in the modern manner, to give clear and economical representation of the rules stated in word language by the medieval logicians, and I sought to organize the materials in a systematic form such as would be used today. I found interesting analogies between medieval and contemporary problems and formulations, as well as notable differences. The book earned me the Haskins Medal of the Mediaeval xv
Preface Academy of America in 1956, and occasioned the presentation to me, in that same year, of the Nicholas Murray Butler Medal ( in silver) which Columbia University awarded for the most distinguished contribution to philosophy made by one of its own graduates during the previous year. Both of these books were published after I had given up my career as a teacher, and had moved to a ranch in Texas to try out the life of a farmer and cattleman. This life lasted for seven years, from 1951 to 1958, and was interrupted only by a return to Columbia as visiting professor in the autumn of 1954, and by a similar visit in the spring of 1957 to the University of California at Los Angeles. It was during this visit to UCLA that I composed the seventh essay of this volume, "Empiricism and Metaphysics in Medieval Philosophy" (reprinted, by permission, from The Philosophical Review, LXVII, 2 [April 1958], 145-163), for delivery at a regional conference on philosophy held at the university. While visiting UCLA I accepted an invitation to join its faculty on a permanent basis, and, after winding up my ranch operation in Texas, I moved to Los Angeles in the summer of 1958. One of the attractions of UCLA, at the time, was the presence of Rudolf Carnap in the philosophy department. This tended to make it an important center for studies in logic and philosophy of language, bringing many distinguished men in these fields to the department as visiting professors and guest lecturers. In this way, during the ensuing years, I was able to exchange ideas concerning medieval work in this area with such men as I. M. Bochenski, Peter Geach, and the late A. N. Prior. With my interest in logic so well nourished, I focused much of my research on the work of the later medieval logicians, and gave particular attention to medieval attempts to resolve problems in the philosophy of language such as are matters of lively controversy today. The ninth and tenth essays in the present volume deal with two such topics. The one entitled "A Quodlibetal Question of Robert Holkot, O. P. on the Problem of the Objects of Knowledge and of Belief' (reprinted, by permission, from Speculum, XXXIX [1964], 53), was built around a text of Holkot which I edited from a single manuscript version that was in my possession. This had value in resolving a few historical questions concerning Holkot and his contemporaries, but the main focus of the study was on the philosophical xvi
Preface problem of the type of entity constituting that which we may be said to know, or to believe. Holkot's extremely nominalistic answer to this problem intrigued me. The other paper, "Buridan and a Dilemma of Nominalism," was written in 1962 as a contribution to The Harry A. Wolfson Jubilee Volume (reprinted, by permission, from the American Academy for Jewish Research), and published at Jerusalem in 1965. It presents Buridan's method of analyzing statements of indirect discourse involving such verbs as 'knows,' 'believes,' 'promises,' and the like—a problem, first treated in modern times by Frege in his well known essay Ueber Sinn und Bedeutung, that had come to be a lively topic of controversy among such contemporary logicians as Carnap, Quine, and Church. Buridan's method of dealing with the problem within the framework of a nominalist ontology seemed to me quite interesting in relation to these discussions. I received helpful comments on both of these essays from W. V. Quine, to whose writings they made reference. The eleventh of the essays in this volume, "The Medieval Contribution to Logic," was written at the request of the editors of Studium Generate, (Jahrg. 19, Heft 8 [Heidelberg, 1966], pp. 443-452). It was a sketch of the development of medieval logic in its historical aspect and in terms of its original contributions. At the time I joined the UCLA faculty there was no more than the usual interest in medieval culture within the modern language departments and in the departments of history and art. But this was destined to change within a very short time, due primarily to the appearance on our campus of Lynn White, jr., who came the same year I did. His own specialty was medieval technology, but he sparked interest in all things medieval and organized our scattered personnel and resources in this field into a cohesive group which later became the UCLA Center for Medieval and Renaissance Studies. The twelfth essay of this volume, "Galileo and his Precursors," was delivered as a paper at a Conference sponsored by the Center to celebrate the four hundredth anniversary of the birth of Galileo. It may be read as something of a postscript to "Galileo and Avempace," in that it offers my considered response to the much debated question of the degree to which seventeenth-century mechanics had its origins in the late medieval period. The eighth essay of this volume, "The Age of Analysis" (reprinted from Proceedings and Addresses of the American Philosophical Assoxvii
Preface cation, X X X V I I [October 1941], 53-67), was my presidential address delivered at the annual meeting of the Pacific Division of the American Philosophical Association. It is not primarily concerned with medieval thought, but with the state of academic philosophy in America and Europe as of the year 1963. But in discussing this subject I could not resist drawing analogies with the medieval "age of analysis" that occurred in the fourteenth century, and in this sense the essay is appropriately included in the present volume. It could indeed serve as a postscript to "Empiricism and Metaphysics in Medieval Philosophy," which sought to establish a perspective on the historical significance of the evolution of philosophy and theology in the Middle Ages. This perspective is also conveyed, indirectly, in the final two essays of this volume, "William of Ockham" (reprinted with permission of the Publisher from the Encyclopedia of Philosophy, Paul Edwards, ed„ 8: 306-317. Copyright ©1967 by MacMillan, Inc.) and "Jean Buridan" (copyright © 1970 American Council of Learned Societies. Reprinted with permission of Charles Scribner's Sons from Volume II of the Dictionary of Scientific Biography). While these articles are primarily devoted to giving a factual account of the lives and achievements of the thinkers dealt with, they present aspects of fourteenth-century philosophy which opened the way to modern conceptions of science and to political and social values that have been distinctive of the modern era. There can be many different motivations impelling a scholar to investigate the thought of a past age. In the case of medieval culture, there have been those whose, main concern was to portray the less attractive side of that age, with its superstitions, cruelties, and ignorance. Others have been attracted to it as an age of faith, and even as a culture to which we should return in a restoration of religious values that the modern age has lost. My own interest in the period has not been of this sort, and in the case of medieval philosophy I have had scant sympathy for the advocates of a return to Saint Thomas and the alleged golden age of scholasticism. Rather, I have been concerned with the way in which some of our most cherished modern ideas, institutions, and values had their origins in the medieval period. As my essay on Jean Buridan suggests, the fourteenth century gave birth to an idea of science and of its appropriate aim and method, which has been distinctive of western culture in modern times. In "Empiricism and Metaphysics in Medieval Philosophy" I sought to xviii
Preface show that the preemption of the domain of speculative metaphysics by a religion based on faith had much to do with this development. Other great creations of the medieval period, formative of our modern culture, were the universities as institutions independent of political and finally of ecclesiastical control, and the concepts of common law and of constitutional government, whose medieval origins have been studied by other scholars in recent years. My studies of medieval thought have been concerned, throughout, with the ancestry of ideas, institutions, and values that we cherish as achievements of modern civilization. Although the Renaissance enthusiasm for classical antiquity led to the labeling of the intervening centuries as the media aetas or "middle age," the intellectual leaders of European culture in the twelfth, thirteenth and fourteenth centuries spoke of themselves as moderni, who had made progress over the heritage of the ancients. My work has been largely devoted to finding those aspects of medieval thought that justify this characterization. I wish to express my gratitude to the University of California Press and its staff in Los Angeles, and to the UCLA Center for Medieval and Renaissance Studies, for making possible the publication of these collected papers, and to the publishers who have kindly given their permission to reprint the essays that originally appeared in their publications. I also want to express my appreciation to Lynn White, jr., who first suggested that I put together this volume of collected papers, for his part in bringing the project to fruition. E. A. M. Camarillo, California
xix
William of Auvergne and His Treatise De Anima I. Introduction 1
William of Auvergne, Bishop of Paris from 1228 until his death in 1249, is of interest to us chiefly because he was one of the first Christian philosophers to have had access to practically the whole body of philosophical literature on which the scholasticism of the thirteenth century was nourished. Despite this fact, the references to him appearing in the extant thirteenth century literature fail, with few exceptions,1 to make any mention of his philosophical doctrines. T o his contemporaries and successors, he was primarily a Bishop, well known for his eloquence and ready wit,2 and universally respected as a conscientious and thoroughly honest servant of the Church. As is so often the case with mediaeval philosophers, few facts about William's life are to be found. The date of his birth is unknown, but it was probably prior to 1190, since in 1225 he was teaching theology at the University of Paris, a privilege not ordinarily accorded to those less than thirty-five years of age. His birthplace was Aurillac in Auvergne, if we may give credence to a note placed at the end of a thirteenth century manuscript, which reads: "Magister Guillelmus de Arvernia, oriundus de Auriliaco.. ."3 Etienne de Bourbon4 tells a story about William of Auvergne as a 1 A notable exception is Roger Bacon, who says (Opus Majus, Bridges' ed., [London, 1900]: III, 47): "Nam universitate convocata bis vidi et audivi venerabilem antistitem dominum Gulielmum Parisiensem Episcopum felicis memoriae coram omnibus sententiare quod intellectus agens non potest esse pars animae." See also S. Thomae Aquinatis Opusculum De forma absolutionis, cap. II: "sic sensisse quosdam antiquos famosos Magistros, scilicet Magistxum Gulielmum de Altissiodoro et Magistxum Gulielmum Alvernum . . ." 2 Valois, p. 147. 3 Quoted by Valois, p. S, n. 3. 4 Lecoy de la Marche: Anecdotes cCEtienne de Bourhon (Paris, 1877), p. 389.
1
William
of
Auvergne
child, which, if true, indicates that William was of poor family. It was said that when he was a child he was one day begging in the street, when a woman offered him alms on condition that he would promise never to become a Bishop. The child, perhaps sensing his destiny, declined the offering. N o indications can be found concerning William's activities prior to the year 1223, when in an official document he is mentioned as a canon of Notre Dame. 5 Again in 1224 and in 1225, two bulls of Pope Honorius III mention William ("magistro W . L'Auvernatz, canonici Parisiensi") in connection with the appointment of clerics to investigate conditions in certain monastic establishments that were apparently in need of reform. 6 From this evidence it may be inferred that William had already made some name for himself as a man of ability, since otherwise he would scarcely have been singled out by the Pope for these commissions. On October 20th, 1227, Bartholomaeus, Bishop of Paris, died. Canon law provided that the selection of a successor, subject of course to Papal approval, belonged to the Chapter of Notre Dame, with the provision that if the Chapter failed to agree with practical unanimity, the right of appointment would revert to the Holy See. The events which led up to William's appointment to the Bishopric of Paris are recounted in detail in the bull of Pope Gregory IX, dated April 10th, 1228.7 It appears that the Chapter first named a certain cantor, Nicholas, but with a considerable minority dissenting. It was William of Auvergne who then stated that the election was not valid, and who threatened to appeal the matter to the Holy See. Thereupon Nicholas asked to be excused from the honour that had just been conferred on him. The majority faction of the Canons, however, not wishing the choice to be taken away from them, voted again and proclaimed the Dean of the Cathedral Bishop, announcing their choice to the public and even singing a T e Deum to celebrate it. William was obdurate, and appealed to Rome. The result was his own appointment to the office by Gregory IX. Cartul. Ste. Opportune, Arch. Nat., Paris, LL93, F o . 11: in Valois, p. 6. Bibl. Nat. Paris, Collect. Moreau, ms. #1183 F o . 11; in Valois, pp. 333-334. 7 Institut Imperial de France: Notices et Extraits des manuscrits de la Bibliothèque Impériale, t. X X I (Paris, 1865), pp. 206-208. T h e Bull speaks of William as "virum eminentis scientiae, vitae ac conversationis honestae, ac opinionis praeclarae, zelum Dei et animarum habentem." 5
6
2
William of Auvergne William's manifold interests and duties as Bishop of Paris have been pictured, with as much completeness as is warranted by the scattered sources available, by Valois. As Bishop he was secular as well as ecclesiastical power, acting as judge, magistrate, diplomat, and official head of the University. Numerous documents authorizing the foundation of new parish churches, and of new monasteries and religious foundations, bear witness to William's conscientious, and even vigorous, fulfillment of his duties.8 Letters addressed to William by the Pope reveal the importance of the Bishop's office from the standpoint of political and diplomatic activities.9 In 1231, for example, William was commanded to act as Papal representative in the peace negotiations between France and England; in 1229 the Pope requested him to send troops to aid him in a war with Frederick II—a request to which the Parisian Bishop responded by sending money instead; in 1246 he was appointed receiver in bankruptcy of the Church of Cologne. There is also a most reproachful letter addressed by Gregory IX to William in 1238, complaining that the Bishop of Paris had failed to defend the rights of immunity of the Chapter of Notre Dame against incursions by officers of the King—St. Louis.10 An affair in which William of Auvergne played a prominent part was the condemnation of the Talmud.11 In 1238 a converted Jew, named Nicholas, drew up a list of thirty-five heretical and anti-Christian doctrines contained in the Talmud, and showed them to Pope Gregory IX. Under date of June 9th, 1239, Gregory wrote to William of Auvergne asking his advice as to what measures should be taken. William, who had no high opinion of the "gens Hebraeorum," advised strong action.12 The result was a Papal bull, issued through William of Auvergne as representative of the Holy See, and sent to all the civil and ecclesiastical authorities. It ordered them to enter all the synagogues on the first Saturday in Lent, 1240, and to confiscate the Jewish sacred books. After this had been done, amidst a great outcry from the Jews, an official investigation by the royal power jointly with the Valois, pp. 40-46. Denifle-Chatelain, t. I, pp. 116-174, contain many of these letters; others are described by Valois, pp. 84-117. 10 Notices et Extraits des Manuscrits de la Bibl. Impériale, t. XXI, p. 210. 1 1 Valois, p.121 fï., gives a detailed account of the whole affair. 1 2 See De legibus (Opp. I, p. 25) for William's opinion of the Jews. 8 9
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leading ecclesiastical authorities of Paris was made into the content of the Jewish books, resulting, in June 1242, in a public burning of the Talmud. It was almost at the beginning of William's tenure of office that the famous strike of the masters and students at the University took place.13 It seems that in February, 1229, the students became somewhat riotous in the course of celebrating the Carnival, so that on the complaint of some citizens whose property had been damaged, the Queenregent Blanche of Castile sent soldiers to disperse the offenders. In the skirmish there was some bloodshed, and the masters and students, enraged at this invasion of their rights of immunity, called on William of Auvergne to obtain redress from the royal authority. When William failed to accomplish anything, the students, feeling that the Bishop was not protecting their interests with due care and energy, suspended all classes and left Paris for neighboring cities.14 It was apparently at this time that William gave a chair in theology to the Dominicans, to help fill the gap caused by the absence of the secular Masters.15 In any case, the striking Masters appealed to the Pope, who then wrote to William, severely rebuking him and ordering him to re-instate the striking clerics.18 The Pope also appointed a commission of two Bishops and an Archdeacon to judge the dispute, in a bull dated Nov. 24th, 1229, and the following May wrote to Blanche of Castile exhorting her to receive kindly the returning Masters.17 Thus the Masters returned to Paris in triumph, with the affair taken out of William's hands. Two points of interest may be 13 Valois, pp. 47-64, gives a good account of the whole affair. Most of the extant documents bearing on the affair are printed in Denifle-Chatelain, t. I, pp. 118-166. 1 4 Denifle-Chatelain, t. I, p. 118, gives the decree of 21 "provisores" of the University, dated March 27, 1229, threatening a six year strike unless redress of their wrongs was obtained within a month from Easter, April 1 J, 1229. 1 5 Denifle-Chatelain, t. I, pp. 252-258, gives a letter addressed in 1255 to all prelates and scholars, in which the regulars, and especially the Dominicans, are accused: "tamen propter quandam atrocem injuriam et famosam nobis illatam translata majori parte studii Parisiensis Andegavis, in ilia paucitate scolarium, quae remansit Parisius, desiderio suo potiti, conniventibus episcopo et cancellario Parisiensibus, qui tunc erant, in absentia magistrorum sollempne magisterium et unam magistralem cathedram sunt adepti . . ." The references to William of Auvergne already cited (p. 1) by Roger Bacon (Franciscan) and by Thomas Aquinas (Dominican) show an immensely higher opinion of William than is indicated in the above "conniventibus episcopo et cancellario." 1« Denifle-Chatelain, t, I, pp. 125-127.
17
Ibid., pp. 127-128, and 128-129.
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mentioned in connection with these events. For one thing, the success of the appeal of the striking Masters to the Pope signalizes the strength of the movement which later culminated in the complete independence of the University from control by the Bishop of Paris. Secondly, if it is true that it was during this strike that the Dominicans were first allowed to teach theology at the University, it becomes easier to understand the antipathy which reigned for some fifty years between the secular Masters and the Mendicants. In 1235 William called the Masters of the University together to discuss the legality of one cleric holding a plurality of benefices,18 a practice which he strongly opposed, and against which he wrote a special tract.19 Again in January, 1241, he convoked the Masters in order to condemn ten heretical propositions, which were proscribed by a proclamation signed by William and the Chancellor Odo. 20 As a matter of fact, the authority of making such condemnations belonged to the Bishop alone, but it was not long before the University began to assume this function in its own right, due in part, very likely, to William's habit of always convoking the Masters as a preliminary to the promulgation of condemnations. Two letters from the Pope, dated June 4, 1238, and Feb. 13, 1245 respectively, reflect the struggle which was going on at this time in connection with the granting of the licentiate. The first, addressed by Gregory IX to the Prior of the Abbey of St. Victor, asks the latter to compose the differences between the Masters and William of Auvergne on the question of granting the licentiate. The second, from Innocent IV to the Masters and Scholars, confirms the agreement made between them and the Bishop and Chancellor on this question.21 1 8 Denifle-Chatelain, t. I, pp. 157-158, gives a quotation from Thomas de Cantimpre, De apibus, I, 1, c. 20, describing two disputes before William, the Masters being convoked, on the plurality of benefices, in 1235 and in 1238. 19 De collatione et singularitate beneficiorum (Opp. II, Supply p- 248). 20 Plessis d'Argentre: Collectio iudiciorum de novis errorilnts (Paris, 1728), 1.1, pars 1, pp. 186-187; also Denifle-Chatelain, 1.1, pp.. 170-171. The ten propositions are of purely theological interest, and include such heresies as denial of the Double Procession, the statement that the divine essence is not in the Holy Spirit in the same way as in the Father and Son, that the bad angels were created evil, and that Adam could not have avoided sin. Of slight philosophical interest are Propositions 4, 6, and 7: (4) "quod animae glorificatae non sunt in caelo empireo cum angelis, nec corpora glorificata erunt ibi, sed in caelo aqueo vel cristallino, quod supra firm amentum est, quod et de beata Virgine praesumitur;" (6) That an angel can be in two places at once; and (7) That there are eternal truths that are not God. 2 1 Denifle-Chatelain, 1.1, pp. 166 and 176.
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William of Auvergne died in 1249, probably on March 30th, and was buried in the Abbey of St. Victor. 22 He was apparently well beloved in his own time, since even the difficult Roger Bacon speaks of him as "Bishop William of Paris, of happy memory," 23 while Etienne de Bourbon testifies to his wit and to his eloquence as a preacher. 24 In a passage in the De Universo William breaks his habitual silence with regard to himself enough to afford a little glimpse into his youth, recalling the other-worldly and essentially Platonic, or Neo-Platonic inspiration which guided him in his studies, before he learned that illumination from above cannot be claimed, but only received as a free gift of grace. Hence it is, that in the time of my youth I thought that the acquisition of the splendour of prophecy, and of great illumination, was easy; for the reason that our souls are, as it were, in contact with both worlds (scil. the spiritual and the corporeal). And so it seemed to me that it was easy to purify our souls from the pollution of sin, easy to break the bonds, or chains, by which our souls are held down and, as it were, imprisoned. . . . For I believed that by a little abstinence, and by turning my soul away from the cares and pleasures that held it captive and which pressed it down into the inferior world of sensible things, my soul would be freed from its obscurity and darkness, and that, through contrary habits those chains and bonds would be broken and consumed; and thus my soul, in freedom, would escape and be able by its own power to break through to the higher realm of light. Now, however, I have learned by long study of divine things, that human souls cannot be purified from the pollution of vice and sin except through virtue and by the grace of the Creator. 25 2 More than twenty treatises of varying length are generally recognized as authentic works of William of Auvergne. 26 The more impor22
Valois, p. 5, n. 3, discusses the conflicting evidence on the date. Roger Bacon, Opus Majus (Bridges' ed.), Ill, 47. 24 Lecoy de la Marche: Anecdotes d'Etienne de Bourbon, p. 388. 25 De Un., p. 1056. 26 Two incomplete editions of William's Opera Omnia were published in 1496, at Nuremberg, and in 1591 at Venice. The best, and most recent edition is that of Orleans, 1674, in two folio volumes. The first volume contains most of the treatises of the Magisterium divinale; the second contains sermons which are inauthenric, but has a Supplement containing the De Trinitate, De anima, and two other tracts. References are to the Orleans edition of 1674. 23
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tant of these formed parts of an encyclopedic undertaking to which William refers as his Magisterium divinale sive sapientiale. While the encyclopedic tradition has a long history, William's undertaking was neither a vast scrap-book like the Etymology of Isidore of Seville, nor a text-book of authorities like the Lombard's Sentences, nor a Summa Théologien composed of Quaestiones. Its aim was to cover the whole field of theology and metaphysics, with relevant questions in physics, logic, morals, and law, by means of original treatises which, while embodying great learning, would enlighten and convince the reader through their own rational discussion as much as by the appeal to authority. The Magisterium divinale was apparently intended to consist of seven parts. William nowhere gives a list of its contents, but Valois has been able to reconstruct the plan and order of the work on the basis of references to its different parts found here and there in William's writings. These seven divisions are as follows:27 I. De Trinitate. Discusses natural theology and the first principles. II. De Universo, 1, /-//. Discusses the sensible or corporeal world. III. De Universo, I, III. The relation of God and creatures. IV. De Universo, II, I-III. The non-corporeal world of angels. V. De Fide et legibus. On faith and the old and new law. VI. De Sacramentis.2s In eight parts, one on the Sacraments in general, and seven on the Sacraments themselves. VII. Summa de Vitiis et Virtutibus. In six parts, as follows: (1) De Virtutibus. (2) Demoribus. (3) De Vitiis et Peccatis. (4) De Temptationibus et Resistentibus. (5) De Meritis. (6) De Retributionibus Sanctorum. In addition to these works, William's published writings include a De Causis seu Cur Deus Homo, a work on prayer called De rhetorica divina, a treatise De collatione et singularitate beneficiorum, a supple27 28
Valois, pp. 195-197. Haureau, in Notices et extraits de quelques manuscrits latins de la Bibl. Nat.,
7
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ment to the work on the Sacraments entitled De Poenitentia novus tractatus, and his treatise on the soul, De anima. There are approximately ten other tracts existing in manuscript which appear to be authentic writings of William of Auvergne, as well as some 530 sermons in manuscript at the Sorbonne, the Bibliothèque Nationale, and at Arras.29 / One other treatise which is included among the published works of William of Auvergne, and which is referred to as his own in his other treatises, is the De imrnortalitate animae. This has been shown to be an almost word for word copy of a treatise of the same title ascribed to Domenicus Gundissalinus.30 It is difficult to account for such obvious plagiarism on the part of the Bishop of Paris, though there are several points that should be taken into consideration. First of all, it is possible that the ascription of this treatise to Gundissalinus is mistaken, and that it is a genuine work of William of Auvergne.31 In the second place, it is possible that William may have seen a copy of such a work by Gundissalinus in his youth, and in later life have thought that the notes he had taken on it were not a copy, but an original treatise merely "inspired" by that of Gundissalinus. It is, however, hard to explain the fact that William in no place mentions Gundissalinus' name, though his writings indicate that he was acquainted with the translations, and probably with the original works, of the Archdeacon of Toledo. Finally, it is possible that there did at one time exist an original treatise by William on the immortality of the soul, which was mixed up by some early copyist with Gundissalinus' treatise, so that the latter wok, instead of the former, was incorporated in the copy of William's writings. As concerns the date of William's literary activities, there have been widely variant opinions. Baumgartner32 ascribed an early date 1.1, p. 186 (Paris, 1890), claims that the De Sacramentis is not authentic. It appears, however, that the De Sacramentis of which he is speaking is a dialogue, attributed in some manuscript to William of Auvergne, which is an entirely different work from the one published in the Orleans edition. 29 Valois, pp. 171-186. The Sermons printed in the Orleans edition are by William Perrauld; those enumerated by Valois are in manuscript only, and are quite distinct from die ones by William Perrauld. 30 For comparative texts and a detailed discussion of the apparent plagiarism, see Dr. G. Bulow: "Des Domenicus Gundissalinus Schrift von der Unsterblichkeit der Seele," in BGPM, B. II, Heft 3 (Munster, 1897). 31 This is the view of A. Masnovo, Da Guglielmo d'Auvergne a S. Tammaso
ental potentate to his subjects; i.e., the view that God is far removed from the created world, ordering it through intermediaries, and caring for it only because it provides an opportunity for displaying his power. I find very little justification for Landry's interpretation in William's work. 9 See chap. 2 for substantiation of this opinion. Also De Un., pp. 851—852; De An., pp. 161,196. 10 De Trinitate, Opp. II, Suppl., p. 8. The real distinction between essence and existence, plus the doctrine that God alone is "ens per essentiam," are in themselves enough to prevent a pantheistic interpretation. See also Schindele, pp. 5862, who reaches the same conclusion.
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though qua mere body the latter has its own corporeal forms which constitute it as a determinate quantity of elementary material substance.11 It cannot be said that William lacked a definite point of view on this question; he did not waver between the two horns of his dilemma, but rejected them both, and, lacking a sufficient metaphysical equipment to express his view in a precise way, he had recourse to analogies. The Platonists, believing that the soul pre-exists and enters the body at birth, faced the problem of explaining how the soul made its entrance into the body; that is, whether it entered it by local motion, or part by part, and whether there was a point at which the soul was only half in the body. This question does not arise for Christians, who consider that the soul is created in the body at birth; but William deals with it, since it would be relevant to the resurrection of the body. In accordance with his previously expressed views, he concludes that it is a false problem: there can be no motion of an incorporeal soul. What happens, then, when the soul "returns" to the body? Only this: the body becomes receptive to the life which the soul has to give it, and returns to obedience in the same way that the subjects in a kingdom become subjects of a new king—not part by part, nor by any motion at all, but all at once. For just as the creator naturally gives himself, spreading into each thing which is receptive of him; so the human soul gives itself naturally to its body as a whole and in its parts, and enters it and flows through it, not by dividing itself nor by dispersion, whereby it would be cut up into parts or rarified; but merely by the integral suffusion of its total being. 12
The analogical explanation is completed by comparing the different bodily organs to the seven planets, which are used by the Creator as instruments of his providence, even though the operations performed through them remain essentially the operations of God. According to this comparison, the heart takes the role of the sun, the brain that of the moon, the spleen that of Saturn, the gall bladder that of Mars, the genital organs that of Venus, the tongue and lips that of Mercury, 11 See De an., p. 196 (quoted n. 47 above); also De an., p. 199: "Et intendo quod ipsa anima per semetipsam, et per hoc quod est anima, operatur vitam corporis sive vivificat corpus, et propter hoc necesse est ipsam esse ubicumque operationem istam perficit."
12
Dean., p. 201. 44
William of Auvergne while the liver corresponds to Jupiter. Aristotle is favoured to the extent of admitting that the heart is the chief instrument of the soul in its operation of vivifying the body. Of these the heart is first, whose harmony is to the sun; for just as the sun is a kind of fountain of life for this inferior and created world—on account of which it is called the father of the vegetables by Aristotle, as the earth is called their mother—, so the heart is like a fountain of life to the human body, and to its individual members. For this reason one of the greatest Italian philosophers says of the sun, that it is the mind of the world. 1 3
The first problem in connection with the relationship of soul and body, namely the problem of how the soul moves and operates the body, is, as we have seen, left without a very satisfactory metaphysical explanation. In rejecting any physiological account, William shows his caution as well as his understanding of the nature of the problem. Indeed, since he has defined the soul as the immediate principle of the life of the body, he needs no further explanation of how the soul moves the body; but his unwillingness to take the full consequences of this definition, through making the soul the substantial form of its body in the full Aristotelian sense, weakens his position; for unless the soul is the substantial form of the body, it cannot be the immediate principle of the body's operations. Sensing this difficulty, William takes refuge in his analogy to the relationship between God and creatures; for God, without being the substantial form of a created being, is nevertheless the immediate principle of the creature's existence. Where this analogy falls down, however, is in the fact that while God, as creator, gives being to created things, the soul only gives life to an already substantial body. Hence the question comes down to this: can a thing have any principle more immediate than the principle of its substantial being? Can one substance act on another except via the substantial form or nature of the other? The only answer to this question, short of the Aristotelian position, lies in the doctrine of a plurality of substantial forms in a single thing. The substance that is formed by the union of prime matter and the first corporeal forms (whether this be the forma corporeitas of later Augustinism or, as in William, the forms of the four elements), func13
Ibid. The reference is to Boethius.
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tions as matter in a further substantial union with the soul as its spiritual form. T h e difficulties of this position became apparent in the philosophies of St. Bonaventura and of Duns Scotus; but it must be concluded that their theories were logical developments from the position taken by William of Auvergne, who wished to bring body and soul into a more than accidental union which would at the same time allow for a substantial distinction between them. 14 2
T h e second set of problems arising in the determination of the relationship between soul and body consists of the questions connected with sense perception and knowledge, by the soul, of corporeal things. That sense perception cannot be a modification of the soul by corporeal things, and that it must be, in the last analysis, an activity of the soul, follows from William's definition of the soul's relation to the body as unilateral, and as analogous to the relation of God to the creation. For William of Auvergne, as for St. Augustin, it is unthinkable that what is merely corporeal and inanimate should be able to affect and modify, by its proper corporeal powers or actions, that which is spiritual. Spirit does not suffer passion in the sense that bodies do—it is not alterable by the action of corporeal agents.15 Such a principle gives rise to difficulties of its own; but at least it enables William to escape the insuperable difficulties attendant on a causal theory of perception, where the external object is supposed to produce a perception of itself in the soul through a series or corporeal events in the sense organs, nervous system, and brain. Intermediaries of a semi-psychic character are of no more value in explaining sense perception than they are in explaining the movement of the body by the soul. T h e theory of the inner senses, and the physiology of the sense organs, can be of value in exhibiting the human organism as a finely integrated instrument; but an instrument cannot operate itself, nor can it produce from its own structure an operator transcending 1 4 Essentially, the problem William is trying to solve in his whole psyéhology, is that which Aquinas states in his Qu. Disp. De anima, art. I: "Utrum anima humana possit esse forma et hoc aliquid." 15 De legibus, Opp. I, p. 55: Arguing against astrological influences on the soul, W . says: "Virtutes ex quibus sunt hujusmodi operationes aut sunt corporales aut sunt spirituales; si corporales, non possunt igitur naturaliter imprimere dispositiones spirituales. Naturales enim operationes sunt per similitudines, agens enim naturaliter intendit dare quod habet, et assimilare sibi recipiens."
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itself. It is essential for the understanding of William's theory of perception to remember his fundamental principle: the soul alone (apart from G o d ) can produce the dispositions and apprehensions that are in the soul, the corporeal cannot act on the spiritual.16 It follows from this principle that sense perception involves two distinct elements, the physiological and the psychical. In both elements the soul is active principle; in the physiological function the soul is to the body (or to the sensory equipment of the body) as operator to instrument; in its psychic function the soul acts in, by, and for itself. Hence William's analysis of sense perception involves a description of the physiological aspects, or of the relationship of corporeal action and passion that exists between the human body and its physical environment; and it also involves an analysis of the act of perception which takes place in the soul, and which is purely immanent and spiritual. I have now shown you that there are two elements in sense perception, namely the reception of an impression from that which is sensed, and the judgment concerning it. The judgment reveals the quality, whereas the reception is an impression of the external sensible form in the sense organ, which is imprinted on it by the sensible agent; very much as the impression that is made by any illuminated or coloured thing in the crystalline humour of the eye is undoubtedly something received. But to judge concerning the quality of this sensible form does not pertain to the crystalline humour, nor is the judgment in it.17 William accepts, with little change, the Aristotelian analysis of the physiology of sensation. The outer senses, according to this theory, are neutral with respect to their proper sensible forms. The eye is actually uncoloured, but in potentiality to the colours of sensible things. Since the qualities of corporeal objects fall into several categories, each group consisting of a pair of contraries and their intermediates, a plurality of sense organs is needed, each organ being in potency to one of the pairs of contraries. Hence the outer senses are selective, and receive only the accidental forms of that which the soul apprehends in its unity. 18 16 De anp. 83: "corporales autem dispositiones non posse esse in subjecto spirituali." "Dean., p. 70. 18 De Un., p. 867: "Sicut enim pupilla oculi abstracta est a coloribus, et ita facta, ut nullius sit in effectu coloris, receptibilis tamen sit omnium colorum, non
41
William of Auvergne T h e distinction of several internal senses, not found in Aristotle, was introduced by William to Latin scholasticism for the first time, having apparently been derived from Avicenna. 19 In the course of his defence of the unity of the soul, William enumerates its different powers, in order to reduce to absurdity the theory that there must be in the human being a separate soul for each kind of human operation. 20 In addition to the vegetative and motive powers, and the five external senses, he mentions five internal sense faculties: common sense, imagination, memory, sense-judgment (vis aestimativa), and sense-reason (vis ratiocinativa). 21 T h e functions of these internal senses are not described in detail, though enough is said of them in various connections to indicate that William understood them in much the same way that the later scholastics did. Insofar as these internal senses are used by the soul in its function as animator and operator of the body, rather than in its role of rational or intellectual spirit, their function corresponds to that of what we nowadays call the nervous system, or the sensory-motor system. T h e y are physiological intermediaries between the action of external things on the organism and its motor reaction. The soul, as immediate prinautem aliorum sensibilium . . . sic facta est virtus intellectiva omnium formarum materialium nuda secundum effectum, potentialiter tamen receptibilis est uniuscujusque eorum. Haec igitur est causa, per quam non recipit in se divisionem vel ramificationem. Sensibiles vero virtutes, quia non operantur, nisi per organa corporea seu corporalia (nec potuit esse organum quod omnium formarum sensibilium esset receptibile) fabricata sunt eis diversa organa ideo sunt divisae, atque ramificatae secundum ilia. Dependentia igitur a corpore cum diversitate formarum sensibilium cum ea contrariete, quam dixi, quam quaedam habent ad quaedam organa, coegit ponere hanc divisionem, et pluralitatem virtutum sensibilium.'" 1 9 Baumgartner: "Die Erkenntnislehre des W. v. Auvergne" BGPM, II, 1, 26. 20 De an., p. 108. A distinct soul as principle of each kind of human operation would necessitate at least fifteen souls in man, says W. It is interesting to contrast William's ready acceptance of Aristotelian principles with respect to the functioning of the body, and with respect to the corporeal in general, with his complete innocence of Aristotelianism in connection with natural theology and the spiritual world in general. He shows no hesitation in adopting hylomorphism in explanation of corporeal changes and activities, but feels no necessity of attempting a similar analysis of spiritual substances. Bonaventura was more consistent, and developed a hylomorphic theory of spiritual substances, attempting to preserve the Augustinian independence of soul from body by the doctrine of the plurality of forms. William, however, merely places Aristotelian physical theory side by side with the Augustinian theory of the soul. 21 Ibid. The distinction between vis aestimativa and vis ratiocinativa is not explained. It would seem that William regarded both as human faculties. 48
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ciple of life in the body, is the operator of the bodily organism with respect to its movements and physical adjustments to its environment; but this whole sensory equipment, as found in animals as well as in man, terminates in motion, and has no immanent or reflective act. This fact is expressed by William when he says that the soul, with respect to its sense powers apart from its intellective powers, "stands outside," and inheres in external things.22 The physiological element of sense perception, which can, in contrast with the term "perception," be called sensation, is an activity of the soul only in the body, and is similar to its other vital functions, such as digestion or involuntary movement. William distinguishes three ways in which the soul of any animal acts in the body. T h e r e are three m o d e s of c o n j u n c t i o n b e t w e e n the soul a n d b o d y , a n d the first of these is life, the s e c o n d , sensation—and w e d o n o t distinguish f r o m sensation those things w h i c h remain in the sense o r g a n s , s u c h as i m a g ination and m e m o r y , f o r these a p p e a r to be sensations that a r e p r e s e r v e d as in a s t o r e h o u s e ( t h e s a u r u s ) . T h e third m o d e is a f f e c t i o n , w h o s e divisions a n d p a r t s are the m o t i v e passions, s u c h as sadness a n d j o y , f e a r a n d a n g e r , a n d others of this kind, i n s o f a r as m e n share t h e m w i t h the other animals 2 3
The first mode of union, which William here calls life, is effected by the vegetative acts of the soul in the body; sense activities, insofar as they constitute a conjunction of soul and body, are, whether they are in the external senses or in the internal senses, purely transitive, and not at all immanent, acts of the soul. The third mode of union, affection, refers not to the immanent or conscious hopes and fears of the human soul, but to what is nowadays called "instinct." 24 Mere sense affections of this type are, as William says, motive passions— their actuality is exhausted and completed in bodily movement, and 22 De virtutibus, Opp. I, p. 153: "Certum enim est bruta exterioribus inhaerere, et in illis sistere, et ut ita dicamus, quasi foris etiam stare. D e intimis vero nihil percipere, nisi quantum vis naturalis aestimariva eis suggerit . . . vis aestimativa solis signis naturalibus utitur, non inquantutn signa sunt, sed inquantum comitantia . . ." Signification is the immanent act of the soul; but the vis aestimativa, though it acts as if by signs, has no immanent significatory power. 23 De legibus, Opp. I, p. 88. 24 T h e conscious correlate of instinct is its corresponding emotion. T h e "motive passions" of animals lack this conscious correlate, though they are named after the corresponding human emotions accompanying similar patterns of reaction.
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does not take on immanent significance in and for the soul of the animal. In other words, the animal soul, or the human soul insofar as it resembles the animal soul, has no immanent or internal act; it is nothing more than the principle of the body's reaction to its environment. T w o consequences of this analysis are: (1) that animal souls are not free, but react in determinate ways to their environment;25 (2) since the vital and motive activities of the soul, even in man, are those which connect soul and body, it follows that in all natural operations of the human composite the vital and motor activities of the soul underlie its higher, or immanent, activities. This is expressed by William in a way which bears a curious resemblance to the modern principle that the motor reaction precedes, in time, the conscious emotional accompaniment.26 Thus the human soul, to the extent that it resembles the soul of any other animal, functions not for itself but for the bodily organism whose principle of life it is. The inner senses are just as external to the soul as the outer senses; they are just as devoid of immanent or perceptual activity as the "crystalline humour" of the eye. William frequently compares the inner senses to books which cannot read themselves, requiring a reader.27 The power of knowing, which is an immanent act of the soul in and for itself, does not reside in the body at all, nor can the series of internal physiological reactions that occur in sensation produce the power of perception. The sense organs, in25 De virtutibus, O p p . I, p. 120: " D e motivis autem inferioribus manifestum est singula consideranti, q u o d necessariae sunt passiones eorum, non liberae ullo m o d o ; et propter h o c dixit A u g u s t i n u s super G e n e s i m ad litteram, quia bruta ex necessitate feruntur, non libertate, seu voluntate." 26 Ibid.., p. 118: " f o r t e v e r u m est q u o d m a j o r i s luminis est anima humana q u a n t u m ad vitam, q u a m q u a n t u m ad sensum vel intellectum; et h o c est, q u o n i a m a propinquiori fluit ex ea vitae radius, q u a m sensus, vel intellectus; similiter forsitan et motus, u n d e et p r i m o ista d u o operatur in c o r p o r e humano, vitam scilicet et m o t u m , et etiam novissime." 27 De an., p. 82: " P r o v i d e v e r o et circumspecte dixi hominem scire et intelligere in anima, quoniam etiam si f o r m a e illae remanerent in o r g a n o imaginationis post animae ipsius recessum, non remanerent tamen scientias in effectu; sunt enim sicut litterae, sive liber, c u m applicatae fuerint per o r g a n u m suum animae humanae. C u m v e r o ab ea separatae fuerint esse litterae, sive liber in effectu; non enim erit aliquid sciens, vel legens per eas in effectu, n e q u e in potentia, nisi forsitan anima ilia cui liber erat deservirent sicut prius, si c o r p u s resumeret, et o r g a n u m imaginationis illas similiter habens inveniret." " A m p l i u s n e m o a d h u c v o c a v i t libros scientiam nisi per abusionem notissimam, essentialiter autem et p r o p r i e nullus u n q u a m opinatus est ut videlicet litterae vel liber scientias essent."
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ternal or external, neither cause perception nor do they perceive; 28 yet it is certain that in some way they enter into the process which terminates in actual perception. Our analysis, so far, has been chiefly confined to the physiological part of sense perception, which in animals other than man constitutes the whole expression of the sensitive faculty. Animal sensitivity is, quite literally, sensitivity of the body to its environment—it is that function which the animal soul carries out in the animal body, whereby the latter reacts as an organized whole to its physical situation. T h e process, in animals, begins and ends with motion, and is neither free nor conscious. It is because this constitutes the limit of the powers that belong to animal souls, that animals are not immortal; they have no active powers beyond those whose function can be fulfilled only in a body, and therefore survival of their souls in separation from their bodies would be "supervacuous." 29 In the human soul, the act of sensitive bodily reaction is generally, though not always, completed or perfected by the immanent act of perception—an act which does not, in itself, issue in any bodily movement, but remains in the soul. In what, then, does perception consist? It is not a motion nor the result of a motion; it is not even a necessary part of the process which commences with the physical alteration of a sense organ, and terminates in a bodily motion or reaction. T h e answer to this question is to be found in William's statement that all cognition is through signs. 28 De an., p. 120: "receptibilitas formarum visibilium non facit oculum potentem videre, sive aptum vel idoneum ad videndum." Cf. De virtutibus, Opp. I, p. 120: "nihil enim potest sensus communis (non impeditus ut diximus) nisi prout recepit a particularibus, et imaginatio similiter, nisi prout recepit a sensu communi, ac si diceretur prout ei traditum est." Also De an., p, 121: "judicatio autem hujusmodi neque in oculo est neque oculi; non enim judicat oculus de coloribus, neque dijudicat inter eos." William is most emphatic in denying that perception is an act of the sense organs, but in spite of this he frequently talks as if it were; e.g. De an., p. 93: "Dico igitur quod sensus omnes sive vires sensibiles sunt et errantcs, sed errores suos corrigere non valentes, sicut evidenter vides in visu qui solem esse bipedalis magnitudinis renunciat tibi, scil. animae tuae." Obviously, if actual perception and judgment is not in the eye, the eye cannot be accused of judging erroneously concerning the size of the sun. Carelessness in phraseology frequently obscures William's thought; his statements usually apply only to their context. 29 De an., p. 72: "omnis anima irrationalis mortalis est . . . et causa in hoc est, quoniam otiosa et supervacua esset vita ejus extra corpus, cum non sit nata operari nisi in corpore, et per illud."
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W e understand as outside of the soul whatever is not the essence of the soul itself, or which is not a part, disposition, or accident of it. F o r whatever is outside our souls is only apprehended by our souls through the impression of its likeness. H e n c e it is that those things which are in our bodies—namely bones, intestines, nerves—are naturally unknown to us, even though they are, in their substantial being, close to us and to our souls; and they are, therefore, outside our souls in the aforementioned manner. I bring up these instances so that you may see that it is not substantial presence or propinquity which effects knowledge, but the impression of a likeness, or the formation of a sign, in our souls. 30 T h i s does n o t mean that w h a t w e k n o w is the sign rather than the thing signified; if this w e r e the case, w e would k n o w the sign itself only b y another sign, and so on ad infinitum.
W h a t it does mean is
that the thing k n o w n is in the soul according to the m o d e o f being of the soul, w h i c h is cognitive. T o k n o w a tree is something different f r o m being a tree; if a man could b e c o m e a tree, he would put forth leaves, but he would not know. K n o w l e d g e is b y signification, and what is k n o w n is that w h i c h is signified rather than the symbol or act b y w h i c h it is signified. 31 Signification is the a c t to w h i c h W i l l i a m frequently refers as the generation of a sign within the soul. 3 2 It constitutes an inner reaction on the part o f the soul t o its own acts as principle o f sensitivity in the De retributionibus sanctorum, Opp. I, p. 318. Ibid.-, "si quis autem dicat, quia juxta hoc quod dicimus, non Deus ipse videbitur ab anima humana in patria, sed imago ejus, quam diximus, licet Aristoteles ad hoc respondisse videtur in libro suo de anima, ubi dicit: Quod imago Leonis picta duobus modis considerari potest, vid., ut imago Leonis, et ut res; et cum consideratur ut imago, non in ea proculdubio sistit intuentis consideratio, sed magis per earn in Leonem extenditur . . . impressio quae fit in oculo a re visa non videtur, sed magis res a qua impressa est, et ad hunc modum se habere de formis et impressionibus imaginabilibus et intelligibilibus, quia non ipsae imaginantur aut intelliguntur, sed magis res, quarum sigillationes et similitudines sunt, nisi forte quis de eis considerationem per se fecerit, quetnadmodum et nos sic loquentes facimus." While it is natural to the human soul to signify things by its direct sensitive reactions to them, in which case the reaction of the sense organ (signified by the sensible form) functions as a "natural sign," the significatory act is wholly the act of the soul, and is not necessarily conditioned by this natural medium of signification. See De an., p. 215: "non est necesse ut omnia signa rerum similitudines earum sint, sicut expresse vides in nominibus rerum, et signa litterarum, inter quae, et res quas significant, nulla est omnino similitudo." 30
31
3 2 De an., p. 215: "ponere res in virtute intellectiva non est nisi ponere signa earum in ilia. . . . Non est autem in ea vel apud earn, nisi per modum quem dixi, vid., per designationem."
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William of Auvergne body. It is, as St. Thomas also expressed it, a reflection or return by the soul from the terminus of its activity in the body to the principle of such activity in the soul.33 In this process, the act of the soul in the sense organ, which in itself has no cognitive value, is given significance by the soul itself, much as a printed word, which in itself is only a group of marks on paper, becomes a sign and acquires meaning through the act of the reader. The question of how the soul can act on itself, in this immanent process of perception, is answered by William as follows. The sensitive act of the soul is numerically distinct from the significatory act of the soul, even though it is the same soul which acts in both cases. Since these modes of activity are numerically distinct from each other, there can be no question of a single substance acting and being acted upon simultaneously in the same respect. The soul, considered in itself, is active only; it is not prior to itself, as agent to patient, but it is prior to its acts, and its acts by one power may be prior to its act by a different power.34 For example, the soul cannot sense itself sensing; but it can understand itself as acting in the sense organs, and this understanding of the sensitive act is undoubtedly posterior to the sensitive act which is thus understood. The problem of sense perception, in William of Auvergne and in thirteenth century philiosophy as a whole, has a setting that is exactly the reverse of most seventeenth century statements of the problem. For William, sensation places the soul in the external object, and understanding is the act whereby the soul returns to itself through reflecting on its sensitive act; the soul is in the world, so to say, before it has any world of its own. Thus the difficulty of later philosophy, 3 3 S. Thomae Aquinatis De veritate, Q. I, art. ix; "in hoc enim quod cognoscunt aliquid extra se positum, quodammodo extra se procedunt; secundum vero quod cognoscunt se cognoscere, jam ad se redire incipiunt." 34 De virtutibus, Opp. I, pp. 107-108: "Alia ergo sunt impressiones in anima, quae generatae sunt per apprehensionem primae operationis, aliae quae per secundam, et illae utique majores et fortiores; non igitur est operatio ista ullo modorum ex illis eisdem cogitationibus et affectionibus, quas per sui apprehensionem generat in prioribus; quare non est inconveniens ullo modo, ut actiones, quae sunt in animabus nostris, agant in eas, et reflectant super eas; neque inconveniens est, ut similes sint in apprehensione cogitationis, et affectiones illis cogitationibus et affectionibus, ex quibus et per quas exeunt; sed omnino inconveniens et impossible est, esse easdem numero; neque inconveniens est animam et agere in se, et pari a seipsa, et haec secundum diversas vires." Ibid., p. 119: "nihil prohibet alteram virium agere in alteram in eadem anima, ut apprehensiva in motivam, quemadmodum imaginatio in desiderativam, sicut dicit Aristoteles."
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where the soul was said to know its subjective reaction before it knew the objective terminus of its action, is nicely avoided. For although the sensitive act occurs first, it cannot be understood except insofar as its external terminus is used to signify the sensitive operation. For all understanding is by signs, and an operation can only be signified as an operation by its terminus. Hence there is no question of how, from a synthesis of subjective "feelings" known immediately by the soul, the soul thence attains its external object of knowledge; such a picture of sense perception inverts the actual order. Sensation is a physical operation conditioned by corporeal substances in interaction with the body; the end of such an operation is attained by the operation—but the operation is understood by its end. In its fundamental characteristics, William of Auvergne's theory of sense perception is thoroughly Augustinian, though it is developed with considerable use of Aristotelian ideas. Its success depends ultimately on the two principles which it presupposes throughout: (1) that the soul, though substantially distinct from the body, is the immediate active principle of the body's operations, and (2) that the soul has, in addition, an immanent act whereby it can signify, for itself, its operations in the bodily senses in terms of the corporeal forms which are the objective termini of these operations. The first of these two principles is supported, as we have seen, through an elaboration of the analogy between the soul body relationship and that of God to the creation, though some indication of the later Augustinian solution, the doctrine of the plurality of forms, is given. The second principle involves the whole question of what fulfills, in William's psychology, the role of the active intellect, as well as his theory of an intellectual "habitus" to account for the apparently spontaneous fecundity of the intellect. These theories will be considered later, in connection with the question of knowledge by intellect. 35 William's theory of sense perception gets along without phantasms. He does use the word occasionally, when referring to Aristotle, but he generally means by phantasm the same thing that he means by intelligible form or sign.36 The intelligible sign is, in William's psychology, not a mere universal (at least not in its pure and natural See chap. 1. De anp. 211: " Q u o n i a m autem non est possibile animam intelligere sine phantasmata, et intendo sine signa vel forma intelligibili." 35
36
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state); it is the soul's inner act of signification of the individual substances that are objects of its sensitive activities, which generates the intelligible sign. Thus the forma intelligibilis, in William's system, fulfills one of the important functions of the phantasm in Aristotle's psychology; it signifies individual sensible substances, but remains intelligible because it is wholly abstracted from material conditions.37 This in turn is possible in William's system because he does not regard matter as the principle of individuation—substances are individutaed by their inmost essence.38 When William speaks of the sensible form, he nearly always means by it the purely physical alteration that occurs in the sense organs (inner or outer) as a result of the interaction between the body and its environment. Sometimes he identifies the phantasm with the sensible form in the imagination, which is located in one of the cells of the brain. Thus, in discussing the question of memory of particular sensibles after death, he distinguishes between memories which are in the soul itself, and those which are only potentially apprehensible, existing merely as physical states of the brain. Since, they say, it is impossible to understand without phantasms, as Aristotle says, and since all phantasms are undoubtedly destroyed by the death of the body, therefore all understanding (according to t h e m ) perishes also. . . . But in answer to this I say that it is possible, and perhaps necessary, that many memories should perish, especially of particular things and of sensible things which are hidden away in the store-house of memory; and I say this because those memories which are in the soul, that is, whose signs are impressed in the soul itself, are not necessarily taken away from the soul by the death of the body. T h o s e memories, on the other hand, which are merely impressed on the aforesaid cellule of the 37 William's position with respect to knowledge of singulars, is the reverse of the Aristotelian view, since he attributes to intellect, but not to sense, perception of the individual. See De an., p. 203: "sensus non attingit ipsas substantias rerum hujusmodi, sed soles dispositiones earum sensibiles; vis vero cognoscitiva superior animae humanae praetendit subesse dispositiones hujusmodi quaedam, hoc autem quoniam sustinet totam illam circumvestionem sensibilium accidentium, potest esse substantia, et haec substantia, de qua dicunt philosophi sequaces Aristotelis quia ipsa est substantia sustinens decern praedicamenta." The attainment by the senses of the sensible dispositions of things is physical—not cognitive: De Un., p. 914: "sensus recipiendo calorem sive passionem ex calido calidus fit." 38 De Un., p. 858: "Et propter hoc quoniam in substantiis suis differunt omnia crcata, sive sint sensibilia, sive intelligibilia, omniaque singularia, videt (intellectus) differentias earum essentiales, per quas nulla earum est alia." This natural ability to know singulars is, however, lost as a result of the Fall.
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brain, and deposited in it as if in a thesaurus, are indeed lost, not only through the death of the body, but by wounds inflicted on this cellule even during life.39 While phantasms, in the role which they fulfill in the Aristotelian system, are unnecessary in William's psychology, he does distinguish between those intelligible forms which are generated in the soul through reflection on its sensitive operations, and those which are actualized in the soul independently of its activity in the body, either by the soul itself through an acquired habitus scientiarum, or by the immediate influence of God.40 Adam and Eve, before the Fall, enjoyed this immediate intuition of the inmost substantial individuality of things within the universal Exemplar, God; sense activity, in this state of innocence, was needed not for knowledge, but only for bodily movements.41 Hence the intelligible forms by which things were known intellectually in the state of innocence, were generated in the soul immediately, through an inward contemplation of God in the soul itself, the latter being the sign and image of God whereby He was known.42 The intelligible forms or signs whereby, in the present state of misery, the human soul knows things, are to be sure generated in the soul by the soul, but not by the purely inward conjunction of the soul to God. Instead of reflecting on the divine Exemplar and thereby knowing created things in their inmost substantial being, the soul can only reflect on its sensitive acts and characterize the external substance by the corporeal dispositions in terms of which these sensitive operDe an., p. 221. De Un., p. 1057: "Mundus autem intelligibilis, sive regio lucis, quae non est nisi aeterna et luminosissima Veritas, quae est creator benedictus, quasi supereminet animae humanae a vertice, et propter hoc quasi contingit earn virtus intellectiva, quae si libera incorruptaque esset, et sana, multo facilius se erigeret ad regionem lucis, et intueretur earn, quam modo se inclinet ut intrat in regionem tenebrarum, sive in mundum sensibilium." Apart from divine illumination, the soul's habitus scientiarum develops in it only through its experience of the sensible world; but once the soul has acquired its knowledge, it is independent of the senses for actualizing it in itself at will. 41 De an., p. 143. The sense of touch, for example, is needed for eating. 42 De retributionibus sanctorum, Opp. I, p. 318: "sic semetipsam intuens mens humana in gloria ilia, non semetipsam proprie videt, sed Deus cujus imago et similitudo tunc est, et repraesentatio pro modo, qui ei congruit, perfecta." Also De Un., p. 816: "Quod omnis intellectus est propter intellectum solius creatoris, et quod est speculum totius universitatis intelligibilibus." 39
40
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ations are signified. It is in this way that the soul is dependent on its sense activities for knowledge of corporeal things, and it is because of this dependence that intellectual knowledge of individual existing things can increase only through experience and the physical contacts of the body. 43 T h e attempt to know the intelligible essences of things, in the present state of corruption of the soul, would appear to be an attempt by the soul to get along with an imitation of its true and natural mode of knowledge, of which it has been deprived. Self-consciousness, whereby the soul in knowing its own operations "from the inside," as it were, knows its own nature, provides an example for the soul of what all its knowledge ought to be like.44 T h e intelligible form which the soul generates in itself through reflecting on its sensitive operations is imperfect as a medium of knowing the external substance in its inner being; it is the soul's improvisation whereby it attempts to exercise its intellectual power without the mediation of God. William uses the illustration of a man who, being deprived of the light of the sun, lights a lantern to show him the way. Another metaphor would be a blind man, whose power of vision is known to him through former use, who now uses his sense of touch as a means of imagining how things look. Knowledge by reflection on sense operations is not, according to William of Auvergne, the natural or perfect mode of human knowledge, though we are forced to it by the consequences of original sin; in the state of innocence, the sensitive operations of the soul were intended only as means of adjusting the body to its corporeal situation and environment. 43 De an., p. 143: "Nunc autem hoc est tempore miseriae et corruptionis praesentis necesse habent animae humanae mendicare a rebus sensibilibus per sensus cognitiones eorum sensibiles, propter obtenebrationes virtutis intellectivae quae ad exteriora particularia et sensibilia penitus caeca est, et ad ilia omnino non attingens nisi sensibus adjuta et aliquatenus illuminata. Sensus enim . . . nihil integritatis percipit, sed usque ad proximum venit, ratio vero quaedam subesse perpendit et intelligit, id est, substantiam subesse varietati sensibilium accidentium. . . . Quapropter a propria luce naturali et intima destituta, mendicat lumina sensuum . . . quemadmodum et nos destituti a luce solari et lumine diei, lucernas nobis accendimus." ^William calls the power of the human soul to know itself the "intellectus adeptus," probably because Alexander of Aphrodisias, and the other commentators who made use of this term, generally took self-knowledge to be the indication of the first actualization of intelligence in man. See De an., p. 217: "declaratio vero hujus est quia intellectus iste est quo ipsa anima humana intelligit se esse intelligentem." That the soul knows itself needs no proof; "non est disputare res ferentes quod est dicere."
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William's analysis of the soul-body relationship preserves the point of view established in his definition of the soul. B y attributing to the soul all the active powers of the human composite, so that both sensation and cognition, and likewise motion and the vegetative powers, are activities of the single substantial soul, he is able to exhibit the processes which are ordinarily looked upon as interactions between soul and body as activities of the soul alone, either in the b o d y or in itself. It is not the body, qua body, that acts on the soul in sense perception; it is the soul qua operator of the sense organs that acts on itself qua intelligence. And in voluntary activity we find the same process of internal interaction, but in the reverse order: the vis motiva superior reacts to the intellectual operation of the soul according to its own proper principle (the g o o d ) , and then generates a movement of the soul qua concupiscible, which in turn acts through the sensory-motor powers of the soul, and finally issues in the movement of the body. T h e soul, while remaining one in essence, is many in operation, 45 and is, as w e saw at the beginning of this chapter, a kingdom of faculties ruling the body. T h e body obeys orders, though it is a distinct substance from the soul; and the explanation of this obedience is found in the point of view that was later expressed b y the doctrine of the plurality of forms, whereby one substance is held to be the immediate principle of operation of another substance. This doctrine is the weak point of this whole psychology; it is the principle on which most of William's other principles rest, but it is itself supported only b y the general analo g y between the soul-body relation and that of G o d and the created world. 4 5 T h e diversity-in-unity of the soul's activity is explained b y an analogy. De virtutibus, O p p . I, p. 118: " Q u i d aliud est multitudo virium in anima humana, aut alia substantia nobili, quam radiositas in Stella? et quid aliud anima humana in corpore humano, quam Stella radiosa in nube? . . . Q u a n t a autem diversitas sit receptibilium radiositatis animae humanae in corpore humano, manifestum est ex ipsa diversitate operationum, et organorum sive membrorum. Ossa enim in corpore humano non recipiunt nisi vitam, oculi autem recipiunt visum et aures auditum, et ad hunc m o d u m se habet de a l i i s . . . . "
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IV. Intellect and Reason 1 The philosophy of William of Auvergne might, with some justice, be described as an attempt to expand the Augustinian tradition so that it would include Aristotelianism and Neo-Platonism at the same time. The influence of Aristotle in logic and the natural sciences came up against the influence of the Arab and Jewish philosophers, and of the Christian mystic tradition, in psychology and metaphysics. William of Auvergne was a melting pot for these widely differing points of view, and though his synthesis contains some confusing elements and unreconciled oppositions, his fundamental Augustinism provides a basis of unity. It is quite in line with the Augustinian point of view to make no distinction between the subject matter of philosophy and that of theology, or between "natural" and "supernatural." This is particularly evident in questions connected with psychology and epistemology: intellectual knowledge of particular corporeal substances is considered to be "natural" to the soul, but lost to it as a result of original sin. The soul is said to have a "natural" aptitude for divine illumination (God concurring), but in this life such illuminations are exceptional, and in a sense unnatural. On the other hand, if we attempt to exclude the explanations that William gives for these less normal occurrences, and confine ourselves to his explanation of human ways of knowing in via, a fairly adequate and consistent theory of knowledge comes to light. It is this path that we shall attempt to follow, though, as will appear, no rigid line can be drawn without danger of distorting William's system. In our analysis of William's theory of sense perception, we saw that he would not allow that the forms of sensible things, as they exist and act in nature, could be efficient causes of the act of perception in the human soul. Neither are they, in the strict sense, material causes of perception; for it is not in the body that the soul actualizes the intelligible sign, but in itself. They are, however, that which is perceived; the things themselves are what is known, and the act of knowledge is the act of the soul and not at all of the things. The 59
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difficulty of this view is that knowledge is regarded as a "passive act," which seems like a contradiction in terms, at least if the same subject is, with respect to what is known, both active and receptive. T h e Arabs, following Aristotle, attempted to solve this problem by positing an active intellect, either separate and unique for all human souls, or else as a faculty of the individual soul. William shows a real appreciation of the usefulness of this doctrine, and of the need of something to fulfill its function. But since the theory of the active intellect, in his eyes, ran counter to such fundamental doctrines as the indivisibility of the soul, or its individual immortality, he refused to entertain it as an acceptable explanation. Yet this problem, of what reduces the intellect from potency to act, remained as the central question around which William built his psychology of intellect; the function of the active intellect as that which abstracts intelligible forms from the phantasms is scarcely considered; the problem that concerns William is almost entirely that of the actualization in the soul of forms or signs that are there potentially. Let me say therefore, in the first place, that there have been philosophers, and others after them w h o thought they were followers of Aristotle, who held that the operation of the intellect, which is understanding, is perfected in two ways—that is, by action, and by passion or reception. A n d on account of this they posited the material intellect as that which is receptive of passions which are signs to the intellect whereby the latter apprehends intelligibles. T h e y also attributed these passions or receptions t o the active intellect, whose operation is to draw forth the aforesaid signs, that are potentially in the material intellect, into actual being, and on account of this they called it the active intellect. Since its act is this, which I have mentioned, and since by its act the intelligible forms or signs are educed, they compared its relation to the material intellect to the relation of light to colours; and according to their opinion, just as light by its radiation brings colours from potential to actual being, so the active intellect brings from potential to actual being the intelligible forms which were potentially in the material intellect. 1
Since the soul is indivisible, says William, it is impossible that this active intellect should be a part of the soul; it must, if it exists, either be a spiritual substance distinct and separate from the soul, or be the soul itself.2 T h e latter view is rejected on logical and empirical De an., p. 20Í. Ibid.: "pars quidem illius esse non potest; iam enim remota est, ut praedixi tibi, ab ea partibilitas, in eis quae praecesserunt." 1
2
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grounds: for to say that the soul itself is active intellect, as well as the substance in which the intelligible forms are actualized or received, destroys the distinction that gave rise to the theory of the active intellect. And in any case, if the soul itself were the active intellect, it would be always in act, and would understand all intelligibles continuously, which is obviously not the case.3 Another possibility, that the forms of things in re actualize themselves in the material intellect, is also rejected. This hypothesis, says William, is founded on the false assumption that because sensible forms enter automatically into the sense organs, without needing any active agent other than themselves, intelligibles can in the same way enter of their own accord into the soul. The fallacy lies in confusing sensation with perception; the reception of the sensible form in the organ is not perception, for perception takes place in the soul and not in the sense organ.4 The only theory of an active intellect which seems to William worthy of. serious consideration, is the theory of a separated active intelligence. He attributes this theory to Aristotle, identifying the active intellect with the tenth celestial intelligence, and also accusing Aristotle of the Arab doctrine that this tenth intelligence creates human souls.5 While he rejects both of these doctrines, he retains the problem and seeks for an equivalent of the separated active intellect. Apparently the theory of the active intellect was very widespread at the time the De anima was written,6 and William never seems quite satisfied with the arguments by which he attempts to dispose of it. Although he states that the human soul is essentially the same as the material intellect,7 insofar as knowledge takes place in the soul, he will not allow that the soul is merely passive in knowledge. One of the inconvenient consequences of the doctrine of the separated active 3 Ibid., p. 206: "Revertar igitur, et dicam quod intellectus agens de quo hie agitur est substantia vivens per se, cum non possit essse substantia corporalis, necesse est earn esse substantiam spiritualem, et cum non sit anima substantia separata spiritualis, et propter hoc intelligens etiam per semetipsam actu continuo intelligent^; si enim potentia tantum intelligens esset, nullo modo congrueret ei nominatio haec qua nominatur intellectus agens."
4
5
Ibid., pp. 205-206.
De an.,
p. 210. Ibid., p. 205: "Et quoniam multi deglutiunt positiones istas absque ulla investigatione discussionis et perscrutationis recipientes illas, et etiam consentientes illis, et pro certissimas eas habentes." 7 Ibid., p. 206: "essentia sua (scil. animae) non est nisi intellectus materialis, et propter hoc intellectus agens . . . nec ipsa essentia ejus est." 6
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intellect is that it leaves the soul without the power of knowing, like a mirror which can receive forms but which cannot itself see them. If the human soul, according to its essence or to its knowledge, were merely the material intellect, and in no sense active—and I mean if it were only receptive of inscriptions or cognitions—it would then be merely a book of descriptions or inscriptions of this kind, but it would be a book only for a reader other than itself, and not for itself.8
Furthermore, if the efficient cause of knowledge in the soul is not the soul itself, but a separated intellect always in act, how explain the fact that the soul does not always and uniformly receive all the knowledge which can be actualized in it, and how explain the fact that learning requires so much effort on our own part?9 These inconveniences seem sufficient to William to make the theory of the active intellect, in this form of it anyway, untenable. So he returns to the Augustinian view that the soul acts on itself and in itself, generating the intelligible signs by which it knows; knowledge is an immanent act, and cannot be accounted for on any other basis. Wherefore it is manifest that the intellect, in us, is not only material and receptive of intelligible forms, but also efficient and generative of them within itself; and this is what one of the greatest of the Christian theologians says. 10
William's respect for Plato and Aristotle is such that when he is forced to disagree with them, he tries his best to re-interpret their statements in a more favorable way. In this case, he is more than ever loath to blame Aristotle for the doctrine of the active intellect, in the form in which he criticizes it, since in his opinion the reasons which caused the Stagirite to posit a separated active intellect are to be found also in Plato's theory of ideas, which in turn has a basis in the Christian doctrine of Exemplarism. Aristotle said concerning the active intellect that it is like an intelligible sun for our souls, and the light of our intellect, illuminating in it actually the intelligible forms which Aristotle held to be potentially in it, and bringglbid., p. 121. 9 Ibid., p. 122. 10 Ibid., p. 122.
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ing them forth from potency into act The cause, however, which forced him to posit this intelligence, was the position of Plato concerning the forms, or the world of species, which is also called the world of archetypes, the world of the principal forms, and the world of intelligibles. For Aristotle was unable to keep from being forced to assent to this position of Plato, though what Plato's reasons or proofs may have been has not been communicated to me. Therefore let me suggest the reasons which he seems to have had, or which he could have had.11 T h e reasons which William attributes to Plato, as the basis for his theory of ideas or achetypes, may be summed up as follows. Since the senses have sensible forms for their proper object, therefore the intellect, which is separate and distinct from the senses, must have intelligible forms as its proper object. Further, since sense affections are similitudes of the object, received by the sense organs, intelligible signs in the soul will have been received b y the soul from external forms that are actually intelligible. For only what is can act, and the cause must be proportionate to the effect; hence there must actually be intelligible forms which can act on the human soul. 12 It follows from this, says William, that there are intelligible signs proper to intelligible things, for otherwise the latter would not be knowable b y us in this life. 13 But Aristotle's mistake, he adds, was in thinking that the intellect abstracts the intelligible forms of things from sensible forms. For if he says that the intellect despoils, and abstracts from their material conditions, the forms which are imprinted by sensibles, and in this way makes them into intelligible forms, and signs of intelligible things; it would follow, in the first place, that nature had neglected the intellectual faculty in us . . . since it needs (according to him) to beg from sensible signs the signs which are necessary to it.14 In confirmation of this, William argues from the fact that it is possible to understand as true, propositions about non-existent things. It 11 12
De Un., p. 821. Ibid.-. "Agere autem,
vel imprimere, non potest, quod non est; necesse igitur est intelligibilia esse, quae hujusmodi similitudines seu passiones imprimunt in intellects nostro." 13 Ibid.-. "Erunt igitur rebus intelligibilibus signa propria intelligibilia, impressa ab eisdem, vel non erunt cognoscibilia nobis . . . intelligibilia." " D e Un., p. 821:
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is true from all eternity, for example, that it is impossible for a man to be a donkey; but this truth cannot be undertstood without intelligible signs, and in cases where a human intellect understands a truth about things of which it has had no sense experience, it is certain that the intelligible signs whereby it understands are not in such cases received by the intellect from sense impressions.15 More obvious still is the fact that the first principles of the sciences, which are known by the intellect per se, are not impressed on it by sensible or particular forms. Nor do these first principles impress themselves on the intellect; for they are universals, and universals cannot act or be acted upon. Aristotle, in spite of his effort to get away from the separated forms of Plato, had to grant that there is in knowledge an element transcending what is given in sense experience; and it is this very element that is the basis of intelligibility. Thus was Aristotle led to his theory of the active intellect, according to William, which was really only the Platonic world of Ideas in disguise. Therefore, since these signs or similitudes, or intelligible forms, have necessarily a cause which impresses them on the soul, and since principles of this kind cannot be the causes which impress them, it is necessary that they are impressed on our souls, according to the intellective power, by some other entity or entities. And since this cannot be done by universals, as Plato seems to have thought, it follows that these impressions are made by something which is particular or singular; and this is what Aristotle called the active intelligence, considering it to be a form full of forms . . . which is to say a formifluous form, a knowledge that makes knowledge (scientiam scientificam), or an intelligence which makes understanding, in accordance with the word of the philosopher who said, every intelligence is full of forms.16
In the above reasoning William finds more than a grain of truth. For insofar as the first principles, and the truth by which the soul knows things, are not made by the soul, but are implanted in its inmost 15 De an., p. 211: "verae sunt quaedam negationes quae, quoniam purae negationes sunt, manifestum est eas non esse, tamen aeternaliter verae sunt; quale est illud non est possibile hominem esse asinum.. . . Quoniam autem non est possibile animam intelligere . . . sine signo vel forma intelligibili . . . manifestum est praedictum exemplum nec sciri, nec intelligi posse quin intelligantur formae hominis et asini . . ." 16 De an., p. 211. Cf. Liber de causis (Bardenhewer p. 173): "Omnis intelligentia plena est formis."
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nature by a supreme intelligence, this position must be granted. Aristotle's mistake was in thinking that a created intelligence, as the separated active intellect was thought to be, could be the light of the soul. Before proceeding to the examination of William's own theory of the intellect, it will be profitable to consider the source of his interpretation of Aristotle, and of such terms as intellectus materialis, intellectus adeptus, etc., which William uses. W e have already remarked on the fact that Alexander of Aphrodisias seems to have enjoyed a considerable vogue at the University of Paris in William's time, a vogue which the Bishop of Paris considered dangerous to Christian doctrine, and worthy of being combatted with every weapon of reason. A comparison of Ch. VII of William's De anima with the De intellectu et intellecto of Alexander, reveals the fact that the popularity of the theory of a separated active intellect, already mentioned, was largely inspired by Alexander, and by the Arab commentators who used his distinction.17 Alexander distinguished four grades of intellect: the material intellect, which is nothing but the potentiality of the human being toward receiving intelligible forms through the influence of the active intelligence; the "acquired intellect," or intellectus adeptus, which is the material intellect endowed with a positive potentiality toward assimilating intelligible forms (the intellect "formally" intelligent); the intellectus qui habet habitum, which is the intellect developed by experience so that it can turn immediately to those intelligible forms relevant to its experience; and finally there is the separated active intellect, which Alexander tended to identify with the divinity. Alfarabi adopted these four distinctions and linked them up with his hierarchy of being;18 Averroes, while opposing Alexandrism with respect to its materialism, made use of the distinctions, and developed the idea of the habitus scientiarum as a convenient way of explaining the fact that study and experience give the human intellect a greater aptitude for being reduced to act, with respect to some intelligibles, than with respect to others.19 The influence of these Alexandrine 17 See G. Thery: Autour du décret de 1210: Alexandre d'Aphrodise (Bibl. Thomiste, VII: Le Saulchoir, Kain, Belgique, 1926), pp. 27-67, for exposition of Alexander's doctrine and its influence on Arab philosophy. Texts of the Latin translations of Alexander's treatises are reprinted, pp. 74-99. 18 G. Thery: Autour du decret de 1210: Alexandre d'Aphrodise, pp. 27-38. 19 Ibid., p. 58.
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distinctions on William of Auvergne, whether he took them direct from Alexander or from the Arab commentators, will appear when we analyze his own theory of intellectual activity. It may here be noted that the interposition of the two additional distinctions between the old Aristotelian active and passive intellects, tended to make the active intellect more than ever remote from the individual human soul, so that this "intelligible light" ceased, in William's theory, to be the tenth sphere, and became merged with the Augustinian "light of truth," which was God. 20 Having thus disposed of the active intellect by identifying it with God, William's problem was to determine whether the human soul has in itself a proper principle of the actualization of intelligibles in itself, or whether it is only a passive mirror receiving its intelligible forms direct from the divine Exemplar.
2
According to William, the doctrine of an active intellect had been introduced by Aristotle and his followers for the sole purpose of explaining how the human intellect is reduced from potency to act. These philosophers were, however, misled by the assumption that a valid analogy could be drawn between the activity and passivity of intellect, and action and passion as found in corporeal things. Aristotle himself recognized the radical difference between the way in which a sense organ receives the sensible form, and the way in which an intelligible form is actualized in the intellect.21 Whereas the act of heating is in the heater, and not in the thing heated except under the form of the reception of heat, this is not analogous to the act of understanding, which is immanent, remaining in the intellect which actually understands. Hence the theory that the act of understanding is the act of a separated active intelligence, in the sense that the act of making the organ of touch actually receptive of heat is in a separate hot sub2 0 Alex. Aphrod., De intellectu et intellecto (in T h e r y , p. 75): "Comparatio autem hujus (intellectus) agentis ad animam, sicut dicit Aristoteles, est sicut comparatio luminis; sicut enim lumen, causa est colorum visorum in potentia ut videantur in effectu, sic haec intelligentia facit intellectum materialem.. . . esse intellectum in effectu." 21 De Un., p. 1018: "nolo te o p i n a r i . . . quod intellectus assimilatur rebus intellectis, juxta m o d u m assimilationis sensuum ad sensibilia . . . sentientes calidum calefimus, intelligentes autem calidum non calefimus."
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stance that comes in contact with the organ of touch, fails to account for understanding in the human intellect. William, afer pointing out these deficiencies in the theory, attacks the problem more constructively. In the first place, since the human intellect is not in act to the full extent of its potential knowledge, but is constantly in process of learning and coming to know what it previously knew only potentially, there must be some power or principle in the soul to account for this movement of knowledge from that which is already known to new knowledge. T h e answer to this is simple; it is by knowing the first principles of a science that we are able to reason to its conclusions. T h e first principles, however, are per se nota, and naturally present to the intellect. Hence no other formal principle is needed to account for the unfolding of knowledge in the soul by reasoning and philosophizing. "Therefore," he says, "the supposition of an active intellect is most futile, and it is a mere figment."22 T h e first principles are naturally present, as principles of the mind's operation in thinking, to the soul. The intellect is determined to them by its very nature, as is shown by the fact that they cannot be doubted or denied, except perhaps verbally. 23 Not only are they self-evident in themselves, but they are capable of making other things evident under the aspect of truth or falsity. 24 William compares them to light, which not only makes itself visible to the eye, but makes all othe things visible as well. 22 De an., p. 209: "cum scientiae principiorum per se sint in intellects materiali, et non per aliud, erunt scientiae conclusionum per scientias illorum in intellectu materiali, et non per aliud . . . figmentum igitur est tantum, et vanissima positio intellectus agentis." 23 De virtutibus, Opp. I, p. 120: "vis enim nostra intellectiva necesse habet consentire primis impressionibus et primis principiis, et omnibus propositionibus quae vocantur communes animarum conceptiones, aut dignitates; similiter et consequentiis sillogismorum, et etiam conclusionibus eorum . . ." Ibid., p. 124: "innata sunt nobis amor boni, et notio veri, intelligens innata, hoc est intus sive ab intimis nostris naturalibus nata." 2 4 De an., p. 210: "manifestum est quod principia scientiarum et doctrinarum, quae per semetipsa nota sunt, lumina sunt per seipsa lumine seu cognitione sua ostendentia conclusiones, et facientia eas relucere ad ipsam, et hoc est facientia ipsas cognosci; propter quod sublatis ipsis vel ignoratis tanquam abscondita luce fit nox spiritualis apud virtutem intellectivam, et ista nox est prohibens videri sive cognosci conclusiones . . . ñeque possibile est ut claudat se visus hujusmodi vel repellat a se . . . vel ut discordât ab eis discredens illa vel ignorans, et hoc est quod Aristóteles intellexit in sermone suo quo dixit quod principiis non est contradicere ad interius rationi."
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T h u s to the spiritual vision, which is the intellect, there- is an intelligible or spiritual light, which reveals itself to the intellect b y itself, and likewise shows to the intellect other things b y means of itself. T h i s however is as if it were said that it is a light in and by itself, which by itself illuminates the intellect . . . and this is to say, that by knowledge of it other things are known. A most evident example of this kind is in the light of the sun, and in the other things which are seen by its light. 2 5
Having thus affirmed that the proximate principle of intellectual activity resides in the soul, in the form of the first principles to which it is determined by nature, William then restates the argument for a separated active intellect in a different form. While it is true, he says, that the first notions and principles whereby the intellect judges, are per se nota, "it may justly be asked whence these signs or forms come into the intellect." 26 Plato, he says, thought that they could impress themselves on the soul; but Aristotle justly criticized Plato's doctrine by pointing out that the first principles are universals, and that univers a l cannot of themselves act or affect anything. 27 There must therefore be something "which is particular or singular," and thus Aristotle was led to posit the tenth celestial intelligence as the effective cause of the presence in the human intellect of the first principles known to it per se.2s William lays stress on the connection between the function of the separated active intelligence as source of the principles of intellectual operation, and as creator of human souls.29 Such a view would be quite logical, if it were possible for a created intelligence to create, since principles per se nota, present by nature in the soul, could only be implanted in it by its creator. And this is precisely the view that William holds as concerns the source of the first principles; their source is in the intelligence which creates human souls, but the only creator is God, and not, as the Arab Peripatetics thought, a created intelligence. A c c o r d i n g to the Christian doctrine which must be most true in all things, and entirely free f r o m all falsity and error, the human soul is placed
,p. 210 Ibid., p. 211.
25Dean. 2®
27 De an., p. 211: "principia universalis sunt, universalis autem vel agere, vel pati non videtur esse possibile." 28 ¡bid., p. 211: "necesse est ut hae impressiones fiant ab aliquo quod sit particulare."
29
Ibid., p. 210. 68
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on the horizon of two worlds, and is there naturally established and ordered. And one of these worlds is the world of sensible things, to which it is closely bound through the body; the other, however, is the Creator himself, who is in himself exemplar, and a mirror of universal and most resplendent appearance, of the first intelligibles. Here truly are all the rules of truth, the first principles I mean, and also the universe of hidden knowables to which the created intellect does not attain except by gift and grace of divine revelation. The creator is thus the eternal truth, and the eternal exemplar of most clear expression and of expressive representation, and is as I said the purest and most spotless mirror of universal appearance.This world, as I said, is joined in the closest way, and immediately present, and naturally placed before the intellect of man; and because of this the human intellect reads in it, without any other medium, the aforesaid principles and rules; out of it, therefore, as from a living book, or an informing mirror, it actualizes by itself these two kinds of rules and principles, and because of this the Creator himself is naturally a book, and near to the human intellect; from him therefore come the impressions with which we are concerned, and the inscriptions of signs in our intellectual faculty.30 T h e above passage sounds very much like Ontologism; certainly it uses phraseology which would indicate that the soul knows by direct illumination from God. But a number of factors make necessary a rather careful reconstruction of such a view. For one thing, William definitely rejects the Platonic theory that the truth of created things is in a world of exemplars, and only by reflection or imitation in the things themselves.31 He distinguishes between terms predicable primarily of God and only secondarily or even equivocally of creatures (such terms as "being, goodness, wisdom, truth"), 3 2 and terms which signify the essences of contingent beings. T h e latter are known to God, but they are in the things themselves, and it is not correct to say that the essence of this fire is in a separated exemplar of fire, rather than in this particular fire. William definitely accepts the Aristotelian solution of the problem of universals, holding that they signify the Ibid., p. 211. De Un., p. 836: "Mundus igitur archetypus, sive exemplaris, nullo modorum est Veritas rerum particularium, hoc est, nullo modorum est vel substantia, vel essentia, vel esse illarum, nisi quis per abusionem intolerabilem dicere velit omnem imaginem, ad cujus similitudinem imago alia fuit, veritatem esse illius." 321bid., p. 837: "Sicut est ens, potens, et potentia, sapiens et sapientia, bonus et bonitas, pulcher et pulchritudo, et his similis, quae secundum depuratam et immixtam contrario per omnia veritatem, soli conveniunt creatori." 3 31
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essences which are in the individuals of the species.33 In view of this, we must interpret William's language concerning God as the universal mirror, to mean that the human intellect knows the essences of things not by a vision of them in God, but by its own formal principle of understanding which is actualized in it by the Creator, and which it knows, through reflection, to be determined toward knowledge of universal truth. A further clue to William's point of view is to be found in his identification of the Platonic world of archetypes with Aristotle's active intelligence, and in turn with what Augustin called the Eternal Truth by which the soul judges.34 For William, God is not the exemplar of particular things except insofar as all things "¡participate," in an analogical sense, in the transcendental attributes such as ens, bonum, verum, etc. It is, however, under the aspect of, or by the light of these transcendental principles that the intellect understands and judges; hence it is by actualizing in the soul these first principles of understanding, that God fulfills the functions of the separated active intellect of Aristotle, and of the Eternal Truth of Augustin, and of the archetypal world of Plato. This would seem to be the only interpretation of William's point of view that harmonizes with the fundamental principles expressed throughout his writings. The "light" which comes from God and illumines the soul, apart from the special cases of supernatural or miraculous visions, is the light by which the intellect is actualized in the formal principles of its operation. It is, as we have already seen, analogous to sunlight in that it makes itself seen (in this case as the self-evident first principles), and by it all other things are seen. This is elsewhere expressed by an elaborate analogy of mirrors. The human intellect is potentially a mirror of all intelligibles: it needs only to be made an actual mirror with respect to one intelligible, to be of itself capable of mirroring any intelligible whatsoever that may be placed before it—for its formal actuality with respect to one intelligible makes it, in the formal sense, an actual intelligence, and therefore involves its possession of the first principles. 33 Ibid., p. 836: "Hujusmodi species totum est esse individuorum; quicquid enim habet Socrates praeter hominem . . . accidit eidem." 34 De virtutibus, Opp. I, p. 114: T h e soul, according to Aristotle, can by its higher powers approach "nobiles regioni lucis, immo ipsi luci aeternae, quae secundum Aristotelem ultima decern intelligentiarum est, et vocat earn intelli-
10
William
of
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Since the intellect is naturally intended to be a mirror, that is, naturally disposed so that all intelligible forms may be reflected in it, therefore it is naturally intended to be a mirror of any form which can naturally be reflected in it. Further. All visible mirrors are fitted to be mirrors of all visible things, and of each one of them. And every visible mirror, when it has become visible actually—i.e., when some visible form has actually been reflected in it, makes every other visible thing an actual mirror, if it is clean and bright, and placed directly opposite it; however, that which visible mirrors do in virtue of their direct opposition to each other, intelligibles do between themselves, by their intelligible mutual conjunction; and according to this, all intelligent substances, by their immediate conjunction to the first universal and resplendent mirror (which is the creator), receive from his irradiation the condition of being in actuality intelligible mirrors. 3 5 A n o t h e r w a y in w h i c h William approaches the question of the relation between G o d and the soul in the act of understanding, is b y s h o w i n g that the end t o w a r d which the soul, qua intelligent, is b y nature determined, is not truth as a mere universal, but a particular being in w h o m all truth is grounded—i.e., G o d . H o w e v e r , in s a y i n g that G o d is the ultimate perfection of intellect, William seems t o mean that the c o m p l e t e actualization of the potential k n o w l e d g e in the soul, depends on the a g e n c y of God—on the function of G o d equivalent t o that of the separated active intellect. A n d this is somewhat different f r o m holding that the soul " s e e s " intelligibles in G o d , as if G o d w e r e a collection of exemplars of individual created things. W i l l i a m keeps fairly close to Augustin's w a y of speaking, w h e r e b y G o d is present to the soul as the truth b y w h i c h it judges—and the w a y in w h i c h the eternal truth is present in the soul is in the first principles b y w h i c h it understands. B u t these principles are "innate," b y the i m m e d i a c y of G o d ' s act of giving being to the soul, and are its> f o r m a l principles of operation; hence they m a y , to this extent, be considered as equivalent t o an active intellect w h i c h is not separated f r o m the soul, but in it. In this w a y William pushes the doctrine of a separated active intellect, as f o u n d in Alexander of Aphrodisias and in Averroes, t o such an extreme degree of separation, that it disappears f r o m p s y c h o l o g y , and gentiam agentem; secundum Platonem vero mundus specierum sive idearum, quem vocat mundum archetypum, et mundum exemplarem, et mundum intelligibilem; Augustinus vero vocat earn aeternam veritatem."
35 Be Un., p. 816.
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of
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is merged with the metaphysics of divine causality. The first principles, actualized in the soul as principles of its natural operation, constitute a proximate formal principle of understanding proper to the soul itself. Their presence gives the soul its habitus scientiarum in potetitia, or a positive power of actualizing knowledge in itself, this is a "first act" of the intellect, whose actus secundus is described by William as habitus scientiarum in effectu, which in turn is nothing else than scientia in effectu.36 What remains to be explained is how the habitus in potentia, which signifies the soul as equipped with its first principles, becomes a habitus in effectu, or the possessor of actual knowledge. In the Thomist system knowledge results from the actualization by the active intellect of the intelligible forms potentially present in the phantasms; but William rejects the doctrine of abstraction in this form. It is this question to which he devotes most of the last part of Ch. VII of his De anima.
3 Insofar as William maintains the self-sufficiency of the intellect, once it receives its first actuality in the form of the first principles, and insofar as he maintains its independence of sense activities in the formation of the intelligible species, he is faced with the difficult task of explaining why the intellect is not completely in act. For if it needs no active agent for this purpose beyond the first principles by whose light all things can be made intelligible, and if all intelligibles are potentially in the material intellect rather than in the sensible phantasms which successively appear in the sense organs, there would seem to be no reason for the discursive character of human knowledge. William's answer to this difficulty is found in a theological point of view which is decidedly Platonic in character—attention to sense activities, to which the soul is unnaturally condemned as a result of original sin, hinders the complete and "natural" actualization of its intellectual powers. The soul of Adam, before the Fall, was created with his intellectual powers uncorrupted by attachment to sensible 36 De Trinitate, Opp. II, p. 20: "habitus scientialis, et scientia in effectu non d i f f e r u n t . . . una et eadum sunt habitus ipse et partus ejus secundum essentiam." 37 De an., p. 136: "quemadmodum sensibilia per sensus se ingerunt animis nostris . . . hoc autem intelligo de puris et reeds animis."
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things, so that the intelligible forms potentially in his intellect were actualized in it without impediment or effort, and were lighted up within him through the presence of the first principles. William compares this immediate and "natural" generation of intelligibles in the soul, in the state of innocence, to the effortless actualization of sensible forms in the sense organs, such as we now experience where no physical impediment is present. 37 T h e corruption of the soul by original sin is described as a rebellion of the lower powers of the soul against its higher powers—or, more accurately, as the perversion of intellect and will whereby they turn away from the first truth and the first good which is their natural object of attention, and occupy themselves with inferior sensible forms. Thus the light of truth is impeded b y the soul's attachment to inferior things, and the operation of the intellect is hindered, delayed, and broken up. W h e r e the perfect and pure intellect would generate wisdom in itself, the corrupt intellect is distracted b y sensible particulars, and gives birth to what William calls intellectual "abortions," which require reasoning and study in order to ripen them into wisdom. When however things are known in their particularity, either through experience or through teaching, the intellect is to that extent frustrated, and as if by abortion gives birth not to wisdom itself, but to parts of it; and on this account it is said that these parts of knowledge require cultivation and time. Thus, in order that it may complete the generation of wisdom, the intellect needs these aids (scil. excogitation and reasoning). . . . But let us suppose that our intellect were of such perfection, that everything which it can do through these aids, it could do of itself alone, and by itself alone; then it would not require cultivation of this kind, or reasoning, but of itself alone, and by itself alone, it would give birth to knowledge, not abortively, nor in parts, nor at diverse times, but all at once. For it has within itself all that is needed for the generation of wisdom.38 Discursive reason thus appears as an operation of the soul which is only necessary to it because of its corruption; since the soul no longer has the purity and freedom which will allow it to generate intelligible forms in itself immediately and without the mediation of sense activities, it uses reason as a means of climbing back from the inferior level of sense experience to the wisdom which is proper to it as an intellec38
De Trinitate, Opp. II, p. 20. 73
William of Auvergne substance.39
tual It is because we must, in our state of corruption, commence our knowledge with reflection on our sense activities, that the possession of wisdom requires continued effort, and the process of learning through discursive reason. By practice and continued study it becomes easier for us to generate intelligibles in our intellect at will, and though in this life we do not attain to the state where all our potential knowledge is capable of immediate actualization, nevertheless, as we master different fields of science we aquire a habitus which enables us to produce intelligible forms in our intellect, relevant to thosefieldsof science, with comparative immediacy and ease. This habitus scientiarum is developed, through study and practice, from the first principles by which we are said to have, from birth, the habitus scientiarum in potential William's theory of an intellectual habitus, together with his theory of the first principles naturally present to the soul, provides his equivalent of the Aristotelian doctrine of the active intellect, in its two functions. First, the presence in the soul of the first principles accounts for the fact that the material intellect is in the first instance, or "formally," reduced from potentiality to act. Secondly, the theory of the habitus acquisitum provides a connecting link between sense experience and the progressive development of knowledge in the soul, since the acquisition of a habitus with respect to any part of knowledge is 39 De anp. 136: "Laesiones autem et impedimenta sunt depressiones phantasiarum, sordes vitiorum, assuetudo nimia circa sensibilia et dissuetudo ab intelligibilibus, sicut dixit unus ex philosophis Latinorum, vid., quia in contemplatione rerum intelligibilium nihil difRcilius est quam a consuetudine oculorum aciem mentis abducere." 40 De an., p. 214: " T u autem vides quod virtus intellectiva ex eo quod est virtus Intellectiva potentia est intelligendi tantum non potens per semetipsam exire in actum intelligendi, sed indiget ut saepe audivisti eductore et adjutore alio. Per habitum vero efficitur non solum potens, sed etiam promptissima, expeditissimaque ad actus intelligendi, et efficitur sicut fons inundantissimus, et copiosissimus inundans in semetipso sive intra semetipsum; non enim est fons sive scaturigo aquarum scientialium sive sapientialium tantum, imo etiam est alveus et receptaculum. " E t ergo hoc quod dico quemadmodum de speculo, de quo certum est tibi quod naturaliter receptibile est, et receptaculum in eo resultabilium substantiarum sive formarum, non autem generativum earum in se ipso, sed extra se tantum, vid., in aliis speculis. Verum si ei vel visui habitu seu frequentia resultationum, ut generativum efficeretur illarum de semetipso absque inspectore generareret illas. et esset non solum speculum, sed etiam speciosum, et intendo speciebus plenum plenitudine redundativa earum. Sic est habitus scientialis vel sapientialis in speculo intellectivae virtutis, videlicet ut plenitudo, et fons redundans sive inundans in eadem scientias in effectu."
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occasioned by sense experience. While William's use of the notion of an acquired habitus is somewhat different, in its purpose and context, from Averroes' use of the idea as a method of accounting for variations in the efficiency of the influence of a separated active intellect on different individuals at different times, the doctrine of habitus is used, in both cases, as an explanation of how sense experience conditions the actualization of intelligible forms in the intellect. As has already been noted, William maintains that the soul ought, if uncorrupted, to actualize intelligibles in itself without reference to its sense activities in the body. Hence he has no use for the Aristotelian doctrine of abstraction; the phantasms of sense are, for him, the occasion of intellectual distraction, rather than "matter" for the abstraction of intelligibles. From the epistemological point of view, the difference between the two theories is marked, but from a strictly psychological standpoint they come to much the same thing. In both theories sense activity is, at least in the present state of corruption, a condition of the actualization of intelligibles in the soul, and in both theories the efficient cause of the act of understanding is the soul itself —in the one case acting in virtue of the first principles present to it a priori, and in the other case acting in virtue of its formal principle of operation, the active intellect. The difference, psychologically, is largely one of emphasis: the Aristotelian emphasizes the continuity between sense experience and understanding, while William minimizes it as far as possible. But from the epistemological point of view, one of the fundamental points of cleavage between Aristotelianism and Augustinism occurs here: the Peripatetic doctrine of abstraction makes knowledge of universals, and of the first principles, dependent (for us) on experience, while the Augustinian rejection of this doctrine commits its defenders (the defenders of Augustinism) to a priorism, in some theory of innate ideas, or divine illumination. William devotes considerable space to the development of a theory of occasionalism, attempting to show by many analogies that everything which is actualized in the soul comes from the potentiality of the soul itself, and not from sense impressions, although the sense activity provides the occasion for an act of the soul which is relevant to the situation that caused the sense impression. Thus he gives the instance of the spider, who, on the occasion of a slight tremor coming to him through his web, forms by his own natural "light" a picture of the fly being caught in his web. IS
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Thus the apprehension, as I said, of the spider with respect to the capture of the fly, is occasioned by the motion or concussion of a thread in his web, but it is effectively or efficiently caused by an innate light, or by an art naturally implanted in the spider. Just as you may see reminiscences and recollections issue forth from the store-house of memory, similarly cognitions and affections (issue forth) from the habits of the sciences, and of the virtues and vices, by the lightest stimuli of external occurrences. This is seen in the example which Aristotle gave of mental aptitude (solertia), i.e., of the man who sees someone talking with the money-changer, and from this concludes that he wishes to get some money changed by him. Here this sight gives the occasion to the quick-witted mind, so that out of it comes this thought, or suspicion. However, it is manifest that the view itself could not in itself be, in any way, the cause of this opinion or suspicion; on the other hand there is no doubt that it is something of an occasion, and that as a kind of help (adminiculum) it favors the formation of the opinion. But the quick-witted mind is in itself the cause of the formation of the thought, which issues forth from it like an overflow, or like a stream from its own source.41 According to William's theory, the intelligible form, generated in the intellect by its own powers on the occasion of sense activity, joins the soul directly, by a "spiritual conjunction," to the thing itself which the form signifies. Such a spiritual conjunction takes place when the soul intends the object, by its act of signification or designation. This act of signification is, except for the fact that it is occasioned as above stated, spontaneous; it is not caused as corporeal events are caused, by the relationship of action and passion. It is not necessary that every issuance from potentiality to act should be through action and passion, as you may see in the issuance of the motive power (of the soul) into motion; otherwise infinites would precede every motion. Thus the intellectual power is of such nature that it receives many signs by even one very slight excitation, and becomes a book of many designations. The reason for this, however, is that a stimulus of this kind applies the soul to things, and joins it to them by a spiritual conjunction.... Thus the intellectual power is of such nature that, when so applied to things, it assimilates to itself, and takes on for itself their similitudes or 41 De Un., p. 928: also p. 929: "Quemadmodum audivisd . . . de intellectu, qui cum nihil patitur a formis materialibus et sensibilibus, per occasionem tamen alienae passionis, scil. quae fit in aliquo ex organis sensuum, exeunt ab ipso novi cogitatus."
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signs; for it is naturally intended to become actually a book, for itself, of the things to which it is thus joined.42 The problem with which William is most deeply concerned, that of how the one indivisible soul can actualize itself in knowledge, is considered to be solved by showing that the first principles are actualized in the soul by the Creator, and that from these, through the many occasions of sense experience, a habitus scientiarum develops the intellectual fecundity of the soul, so that it becomes a fountain of intelligible signs that overflows into itself. The analogy to the Trinity illustrates the theory—God the Father, the completely actual generator of the Word, is a habitus sapientiae completely in act, and is therefore one in essence with the Son, who is Sapientia in effectu. The one God, however, is not generative and generated in the same respect, but only with respect to the paternity and filiation within the Godhead.43 According to William, the immanent activity of the intellect in knowledge is similar; the soul in understanding is both active and receptive, but it is nevertheless one in essence, and its activity and receptivity do not contradict its essential unity. One further question to be determined is that of intellectual knowledge of singulars. While William denies that we can know singulars intellectually in this life, except insofar as we infer the individuality of a substance underlying the variety of accidents to which our sense operations introduce us, he maintains firmly that in its state of perfection the intellect knows individuals in their inmost individual substantial being. Otherwise, he says, we could never know God, who is 42 43
De an., p. 215. Ibid., p. 214: "Determinatum
igitur est tibi per hoc quod virtus intellectiva non est agens et patiens scientias in effectu, neque dans et recipiens illas secundum idem, sed recipiens est illis ex naturali aptitudine seu receptibilitate sua. Dans vero sive inundans illas est ex plenitudine hoc est ex habitu redundante in earn, et intra earn. E t quoniam plenitudo hujusmodi habitus tanquam fons est scientiarum actualium inundans eas de se in capacitatem sive amplitudinem atque profunditatem virtutis intellectivae, quemadmodum in alveum propriuni; et est nonnulla similitudo inter generationem scientiae seu sapientiae actuali, de qua agitur hie, et generationem primogenitae sapientiae quae est Dei altissimi filius. Sicut enim Deus pater de propriae foecunditatis plenitudine, eructavit verbum illud bonum, quod est dicere genuit intra semetipsum; sic vis intellectiva quasi impraegnata et foecundata hujusmodi habitu de plenitudine illius eructat et gignit scientias in effectu in semeripsa, et intra semetipsam; scientiam autem in effectu non intelligo nisi formas intelligibiles sive signa intellectualia resultantia in effectu, et actu apparentia in speculo virtutis intellectivae." Cf. De Trin., Opp. II, p. 20.
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an individual; yet knowledge of God is the perfection of intellect, and the end for which it was created. 44 The possibility of an intellectual knowledge of singulars is grounded in William's theory that substance is the principle of individuation. 45 He does not, however, go so far as to say that Socrates and Plato are specifically or essentially different. William holds that whatever is in Socrates beyond the essence "man" is accidental. But while Socrates and Plato are essentially one in species, they are numerically diverse; William distinguishes between similarity, which is the basis of specific identity, and numerical identity, or, conversely, between the dissimilarity which exists between different species, and the diversity which exists between individuals of the same species. This diversity of individuals within the species is not accidental; Socrates and Plato are essentially diverse individual men, and their diversity is not due to accidental characteristics, nor to matter. The universal, on this view, signifies diverse essences that are completely similar to one another; in this life we only know essences according to their universal character of similarity in kind. But the perfected intellect will know them also according to their diversity of being; that is, the perfected intellect will know substances not only by their species, but by their substantial being. In this life, William concedes, the basis of our distinction between individuals of the same species is in their accidental differences, from which we infer their substantial individuality, though this can only be signified by the common essence. This is brought out quite clearly in a passage where William "explains away" Boethius' statement that accidental differences make the numerical distinction between individuals of the same species. Let not the w o r d s of a certain Italian philosopher disturb you, where he said that only the variety of accidents makes numerical difference, for his meaning in this was only to exclude specific or other substantial differences, or to refer the meaning of his w o r d s to us, in the sense that this numerical distinction is a distinction of our minds. F o r it was his intention in this passage, that only the difference of accidents (i.e., not the species or substantial
De anp. 203. De Un., p. 858: "in substantiis suis differunt omnia creata" . . . "Intellectus videt interiora omnia, hoc est, ipsa substantialia rerum. . . . Hoc autem non putes me dicere de intellecm in corpore quodammodo demcrso . . . sed de intellects glorificato." 44 45
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difference, or any of the common essentials) makes numerical difference, or diversifies the individual itself, or makes for us the numerical distinction between individuals. For we do not distinguish individuals within the species, but rather we unite, by the essential similitude, whatever belongs to them in the species, or rather, whatever the species itself is in itself. He himself says that the species is the substantial similitude of the individuals, and you should understand that I said substantial—i.e., according to the whole substance; for beyond the connotation (ratio) of the species, the individual has nothing that is substantial. This kind of similitude, mark you, is commonly called identity in species. Do not doubt that if our intellect were now illumined with the illumination of its final glory, it would distinguish and number within the species itself, not however by dissimilitude, since there is none in the same species, but by diversity, whereby it sees that this is not that, and vice versa; and it would most accurately number, and call things one, and another, and the third. But in the present state of dark misery it is not illuminated so as to number them and distinguish them, except through the accidental differences—that is, sensible accidents—unless perhaps by prophetic splendour, or by some other irradiation coming to it from above, it is given the power to do this. 46 Leaving out of consideration this intellectual knowledge of singulars in their substantiality, which is not possessed in this life, there is nevertheless a distinction, in William's psychology, between intelligible signs which intend individual substances, as individuals, and those which signify the species as a universal. This distinction has some c o r respondence to that between the phantasms and the intelligible species, in the Thomist system; the similarity is found in the fact that the signification of individuals as individuals, in this life, is bound up with the awareness of the distinguishing sensible accidents, while the signification of the essence, as a universal, is attained by abstraction from these sensible accidents, or material conditions. William lists three modes of knowledge, apart from the a priori knowledge which we have of the first principles, that characterize human intellectual activity: knowledge based on sense perception; knowledge of species as universals, obtained by abstraction; and knowledge of relations. It is manifest that our intellectual power is receptive of information, illumination, and inscription from the inferior world according to the 46 De Un., p. 802. Cf. De Vn., p. 858, and the Appendix at the end of this chapter.
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modes which y o u have heard. T h i s however happens in three ways. First by sense, which introduces t o the intellect sensible substances, and intellectual substances which are joined t o bodies. T o be sure it (sense) does not paint their intelligible forms in the intellect, since it does n o t itself receive these forms; but the intellect, by itself alone, reaches out t o these substances beneath the variety of sensible accidents. T h u s the intellect apprehends, o r sees, substances of this kind beneath a covering. 4 7
Elsewhere he describes the process whereby the intellect forms the intelligible species by which it knows the individual, as a process of inference from the sensible accidents to their cause.48 It would seem to be little more than the judgment by which the soul concludes that the terminus of its sense activities is an individual existing substance of such kind as to be characterized by these sensible accidents. The second way is by abstraction, which William calls "denudation" or "despoiling." It is the consideration of the essential characters of individuals within the same species without determinate reference to the individuals; and this is accomplished by disregarding the "garment of accidents" which clothes the individual, and considering only the essential character which all members of the class possess in common. William speaks of this as if it were a secondary act of the mind, independent of the process of understanding the essence in the individual; abstraction, in his view, is the process of removing individualizing characteristics from an idea of a substance, so that the residue will signify all individuals of the species.49 The third way is by "connection or binding together," and is the sort of knowledge that comes from knowing one thing in terms of its relation to another, as the correlative is known if the relative is known. The causal interconnection of things corresponds with the essential 47
De an.,
p. 213. De Un., p. 1057: "mundus iste sensibilis . . . est regio tenebrarum quantum ad virtutem intellectivam animarum nostrarum, quoniam ipsa . . . a parte mundi inferioris illuminatur ad cognoscenda, quae per hoc possunt cognosci, sicut per motum ad causam motus cognoscendam." 49 De an., p. 213: "Secundus modus est per abstractionem; et jam declaratum est tibi quid sit abstractio seu spoliatio aut denudatio; haec enim non est nisi privatio apprehensionis formarum individuantium sive individualium, et posui tibi exemplum de hoc in imagine Herculis eidem simillima, et intendo quae clare videnti et e proximo inspicienti non nisi Herculem repraesentare posset. Si autem elongaretur ab ilia pro modo elongationis, imminueretur apprehensio formarum hujusmodi; donee veniret ad hoc ut imago ilia non repraesentaret ei nisi hominem vagum, non potius unum quam aliam." 48
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relationships that reason traces in its work of analysis; thus the understanding of essences in the light of the first principles per se nota, leads to knowledge of causes and effects, and thus to the formation of a habitus scientiarum with respect to all that is in this way understood.50 Through the rather elaborate psychological analysis which has been outlined, William seeks to justify the validity of knowledge by universals, and by demonstration "propter quid" and "quia," without compromising his theological conviction that the human intellect in this life is corrupt and imperfect. By a number of ingenious theories and analogies, he pictures the intellect as essentially and "naturally" intellectual in the sense that angels are intellectual; the use of sense perception, instead of an inward illumination by the eternal truth that is present to the soul in the form of the first principles, is looked upon as an unnatural perversion of the intellect made necessary only by its corruption; likewise reasoning, whereby the broken pieces of knowledge that come to us through the prism of sense perception are partially bound together and restored to their purer intellectual unity, is a remedy of imperfection necessitated only by our intellectual corruption. What gives William's analysis its philosophic interest is the sincere effort he makes toward fitting his theory to the problems raised by the Aristotelian approach to psychology and epistemology. He does not, like some other Augustinians, disregard problems which appear in the Peripatetic approach, with the claim that the light of Christian truth makes such problems irrelevant or unimportant; but he makes every effort to give an answer, in terms of his principles, to all the important questions raised by the Peripatetics and Arabs whose alternative theories he is criticizing. As a result, he has to expand the Augustinian doctrine in the direction of Aristotelianism, by finding equivalents for the elements which appear in the latter; and thus we find William using many detached theories borrowed from Aristotle, Alexander of Aphrodisias, and the Arabs, and finding a place for them within the Augustinian point of view. Hence, whatever the shortcomings of the 50 De an., p. 213: "Tertius modus est per connexionem sive per colligationem, et intendo quod quaedam res colligatae sunt quousque ad invicem, ut sicut una sine altera esse non potest, sic neque cognitio alterius sine cognitione reliquae. . . ." Ibid., p. 21 J: "omnes res propter colligationes . . . antedictae viae sunt aliae ad alias, et intus ducunt aliae ad alias virtutem intellectivam juxta modos quos audivisti, sicut causa introducit effectus ad illam, et effectus ad causam."
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system, the fact remains that William of Auvergne was one of the first philosophers of the thirteenth century to try conscientiously to meet Peripateticism on its own ground, and by this attempt he may be said to have prepared the way for those who, like Thomas Aquinas, undertook to develop a Christian Peripateticism.
Appendix
to IV
William of Auvergne, throughout his writings, seems to put great faith in Boethius on all questions of logic and metaphysics. The wellknown passage of the Italian philosopher, where he says that accidents make the numerical difference between individuals, worries William considerably, and causes him on several occasions to give elaborate expositions of Boethius' real meaning. The following quotation, from De Universo, II, II, c. 15 (Opp. I, pp. 858-859) is one of them: Sensus enim sola forinseca apprehendit; de interioribus vero, vel intimis nihil, sicut dicit quidam ex philosophis latinorum. Sensus inquit nihil integritatis percipit, sed usque ad proximum venit. Ratio vero quaedam subesse perpendit. Intellectus igitur videt interiora omnia, hoc est, ipsa substantialia rerum, ipsaque substantias earum. Et propter hoc quoniam in substantiis suis differunt omnia creata, sive sint sensibilia, sive intelligibilia, omniaque singularia, videt differentias earum essentiales, per quas nulla earum est alia; sicut enim hoc non est hoc, nisi per hoc, quod est, hoc est dicere non a foris, neque ab aliquo quod sit post esse ipsius, et supra id adveniens, sicut, quod hoc non est illud, non est ex forinsecis, neque accidentalis differentia, sed diversitas et differentia essentialis. Hanc igitur videt intellectus, qui videt intus, ubi ista diversitas est. Sensus vero inter simillima sensibilia diversitatem non videt, nisi ad intus, quemadmodum dixi. Intellectus vero totum pénétrât, quemadmodum dicitur de visu lyncis. Hoc autem non putes me dicere de intellectu in corpore quodammodo demerso atque sepulto, et originali nostra corrupdone obscurato, fantasiisque depresso, sed de intellectu (ut Christianorum utar sermone) glorificato. Terno vero causa hujusmodi erroris fuit ignorantia penetrationis et profundationis intellectus in intima intelligibilium. Haec autem sunt substantiae, et substantiae illorum, et differentiae essentiales ipsorum, quae faciunt diversitates secundum numerum. Erraverunt etiam hujusmodi homines decepti aequivocationes ejus, quod unum est. Cum enim refertur ad speciem, hoc est, cum dicitur unum specie, intentio ejus non est nisi similitudo essentialis. Species enim (ut ait idem philosophus) substantialis 82
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est, et intelligitur secundum totum. Non enim sunt unum specie, nisi ea, quae essentialiter, atque totaliter, hoc est, secundum totas substantias, similia sunt. Quae vero genere tantummodo unum, vel idem sunt, non totaliter, nec integre, sed secundum partem substantiarum suarum tantum similia sunt, quoniam secundum unum eorum, quod intentio seu ratio generis continet.... Intellectus igitur noster in his tenebris et in hac depressione, in qua sumus hic, non distinguit ad nudum Socratem a Platone in hac specie homo. Quoniam nec ad nudum et clarum penetrai apprehensio ejus, nec intrat in illam. In gloria tamen futura sua ad nudum, et clarissime intuebitur eorum diversitatem numero, per quam solam numerantur, et per quam solam vere ac proprie dicitur hoc, et illud unum, et alius unus, et alius alter, et reliquis, non autem ullo modorum per varietatem accidentium. Et sermo, quo iste philosophus Italicus dicit, quia sola accidentium varietas facit differentiam numero, intelligendus est (ut praedixi tibi) per subauditum, quod subauditur, nobis videlicet, in his tenebris constitutis, per quas prohibetur (ut praedixi tibi) intellectus noster penetrare ad nudum, et videre ad liquidum intima sensibilium substantiarum, quae in presenti non videt, nisi velata id est quasi sub operimento varietatis sensibilium accidentium. In maintaining that the principle of individuation is substance itself, William includes in substance the esse as well as the essentia; thus he is not so far from the Thomist theory that matter is the principle of individuation, for his own doctrine amounts to little more than the Aristotelian dictum that all individuals are first substances, and that first substances alone exist. Intellectual knowledge of singulars, which William promises to souls in their beatitude, is equivalent to intellectual knowledge of matter such as God has.
V . Freedom
and
Immortality—Conclusion
1 In William of Auvergne's analogy of the soul to a kingdom, the king is always the analogue of the will, and intellect is represented as the royal counsellor. Beneath these two superior faculties are placed the "executive motive powers," which are like sheriffs who carry out the
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William of Auvergne royal commands, and reason, which is a judge applying the laws of the kingdom to particular cases by means of a syllogism in Darii. So far it has been shown that the will, like a king or emperor, is free and sovereign in all those things which are placed beneath us, and that the inferior motive powers are by full right placed beneath it, like servants ready to carry out all its commands. . . . T h e intellect is like a counsellor. T h e reason however is like a judge of the minor premiss, or a witness. When, therefore, the will follows the counsel of intellect in its commands, it administers its kingdom prudently; when it judges according to reason, it enacts justice and judgment in its whole kingdom. 1
The inferior motive powers are five: the appetitive, digestive, and expulsive, and the concupiscible and irascible powers.2 The first three, which are generally regarded as involuntary, are probably excluded from the domain of the kingly power of the will, and the instruments of all voluntary motions remain the concupiscible and irascible powers. Where he speaks of the inferior "executive" powers, William mentions only reason, which is a kind of minor administrator of the higher commands. Probably the internal senses, such as the estimative power and the imagination, also function as executive instruments in carrying out the commands of the will. The immediate object of the inferior activities of the soul is always something concrete and particular; the proper object of will and intellect, on the other hand, is the good and the true—in its perfection, God, and in its imperfection, the signs of God which are to be seen in the world of created things. For while the natural perfection of the soul is knowledge of God, original sin has turned the human soul away from the immediate communion with God, so that it now knows Him only under the cloud of the created universe,3 while its higher motive faculty is detemined only to act for the vague end of happiness, and does not directly perceive that its sole complete happiness is in God alone.4
De virtutibus, Opp. I, p. 122. De an., p. 108.
1 2
aDe Un., p. 867: "Quoniam nec ipsum creatorem, nisi tanquam sub nube universi, et gubernationis ipsius" (scil. cognoscit intellectus humanus in hoc statu miseriae). 4 De legibus, Opp. I, p. 84: "Amor Dei et desiderium beatitudinis nobis innata sint, et indita, sicut et fuga miseriae." The love of God, however, without knowledge of Him, involves faith as its vehicle.
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William's ethics are thoroughly Augustinian, in that the goods of this world are, in relation to the higher faculties of the soul, purely of instrumental value. 5 Intellectual knowledge of particular things, or of the sciences, is not an end in itself; indeed it is an evil if it causes the soul to stop in via, and t o forget to regard things as signposts leading t o eternity. 6 O n the other hand, the pure soul w h o has attained beatitude, and whose intellect is perfected in the knowledge of God, enjoys without evil the knowledge of the sciences and of created things, which under these conditions have a certain intrinsic value which, though adding nothing to the fullness of perfection received in the contemplation of God, are nevertheless good as "ornaments" t o the soul. 7 F o r William, as for St. Thomas, the Augustinian and Aristotelian notions of the good are not incompatible; from the theological point of view, where the attainment of salvation is the dominant theme, the goods of this world are regarded only in their role as signs of the supreme G o o d which they imitate; but from the philosophical viewpoint, where the question of salvation is omitted, positive value m a y be ascribed to every object of human activity insofar as it perfects and actualizes the faculties of the soul. Since the highest perfection of the soul is knowledge, the highest good of the soul is t o be found 5 De Un., p. 816: "omnis intellectus est propter intellectum solius creatoris." Ibid., p. 721: "Sicut nata est vis intellectiva cognoscere creatorem, et videre veritatem seu claritatem ipsius, sic nata est vis affectiva seu desiderativa superior et nobilis, sentire bonitatem ipsius." De an., p. 130: "Propter hoc debet esse manifestum tibi quod per hanc corruptionem incurvantur animae nostrae ad ea bona quae post nos et sub nobis sunt, quae nominantur terrena, temporalia, transitoria." 6 De Un., p. 720: The soul is separated from God in three ways: by evil (dissimilitude to God), by failing to regard created things as signs of God, and by devotion to sensible things. "Secundo vero tanquam distantiam spiritualem facit aliud apprehensum, cum via non fuerit ad apprehendendum creatorem. Hie autem est, cum fieret apprehensum, ut res. Reminisci namque debes sermonis, qucm dixit Aristoteles, quia imago leonis apprehenditur quandoque ut res, et quandoque ut signum; et cum apprehenditur ut res, stat in ea et figitur in ea apprchensio, et non pervenit ad leonem. Cum apprehenditur ut signum, non stat in ea apprehensio, sed transit ad leonem. . . . Et juxta istos duos modos currit res in omnibus creaturis, et creatore; quoniam quaelibet creatura et res est in se, et via ad apprehensionem creatoris, et signum est ipsius intelligentibus." 7 De an., p. 222: "Quod licet scientiae non erunt necessariae ad foelicitatem, tamen ad decorem et ornatum ipsius beatitudinis probabile est eas remanere." "debes tamen scire quod nulla scientia infructuosa simpliciter est, quia etsi alius fructus ex ilia non sit, ipsa tamen in semetipsa perfectio quaedam est." In glory, says William, things will be known by divine illumination through "scientia propter quid"—but this is not incompatible with the retention of "scientia quia."
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wherever actual understanding is attainable; from the theological point of view, this highest good is to be attained by faith in this life which brings salvation, and knowledge of God, in the next. From the philosophical point of view, the partial truths and goods of this world are to be enjoyed, as well as used for the attainment of the more complete wisdom.8 When speaking from the theological viewpoint, William insists on the superiority of will over intellect. 0 This does not mean that he is a voluntarist in the sense that volition is regarded as an end in itself; when ascribing superiority to the will over the intellect, he is considering both faculties as means to the end of beatitude—but beatitude itself is intellectual. Understanding is the most perfect of all acts, as we may know from the fact that the Word is generated within the Godhead by the act of understanding, whereas the creation of the world, by fiat, is posterior to the divine immanent act. Although the divine intellect is completely self-sufficient, the human intellect, even in beatitude, needs God for its perfection; since it can attain God's light through love without knowledge, but not through knowledge without love, the will is superior as a means to beatific illumination, in comparison with the intellect in its present imperfect state.10 William frequently contrasts scientia with sapientia. T h e former, he says, gives us knowledge of things from the outside, whereas wisdom penetrates to the hidden interior nature of things, and, as it were, tastes them while seeing them. This is shown etymologically by the fact that sapientia is similar to sapor, or taste. It is this intimate interior communion with the "thing-in-itself" which, in knowledge by sapientia, takes the place of "feeling" which in this life is supplied by the bodily senses; it is this which keeps purely intellectual knowledge, among the beatified, from being coldly intellectual and abstract. 11 8 De an., p. 212: " D i c o igitur quod duo sunt circa quae naturaliter versantur, et in quae naturaliter intendunt, et ad quae habent conversionem suam sive incli-i nationem naturalem virtus intellectiva . . . et vis motiva nobilis. . . . H a e c autem duo sunt Veritas et bonitas, quae autem inquirunt ex his duobus duae istae vires sunt illuminatio, et jocundatio." 9 Ibid., p. 219: "vis intellectiva etiam . . . principaliter propter vim motivam nobilcm est . . ."
10
De Trivitate, Opp. II, p. 21.
De an., p. 100: "rerum sapores sunt rebus intimiores . . . quam dispositiones exteriores . . ." 11
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For the sense of which we are speaking, is intimate knowledge, nor is feeling anything other than intimate and immediate knowledge; hence he who knows the divine goodness intimately and immediately, necessarily feels it, but feels it as it is, and on this account feels it as most delectable; and this sense of the divine suavity is the interior taste of wisdom.12 T h e distinction between intellect and will, in the human soul, is of course a distinction between functions. Hence William asserts that the will knows and apprehends, and that the intellect is a "mover" as well as a faculty that is moved; 1 3 the basis of such statements being the fact that it is the soul which understands and wills in any case. Thus will moves intellect with respect to the end to be attained (which is "the g o o d " ) , while intellect moves the will with respect to the determination of the means of attaining the good. William emphasizes the intimate connection between the two faculties to such an extent that their distinction tends to be obliterated, and the will to be conceived as exercising the functions of intellect in its own right. 14 In general, when he is considering the soul in relation to its operations in the body and in this life, he accords primacy to the will; but when he is considering the soul in relation to its beatific perfection, he stresses its capacity for wisdom and for intellectual illumination. 15 T h e primacy which William, like other Augustinians, accords to the will, is simply a consequence of the primacy accorded to the theological point of view in questions of metaphysics and psychology. William also adheres to the usual Scholastic tenet that the complete freedom of the human will is found in the complete service of God. 1 6 This follows from the fact that the soul is by nature completely perfectible by G o d alone; since knowledge and love of the Creator constitute the only perfect actualization of the soul, a man becomes most completely himself when he gives his intellect and will most completely to this knowledge and love. This is analogous to material bodies and their proper places; as long as they fail to be at rest in their 12 13
14 15
De virtutibus, Opp. I, p. 147.
De an., pp. 96-97.
Ibid., p. 99. De legibus,
O p p . I, p. 77: " U t deitas sit in non intelligente est impossibile, hoc enim est quo potissimum anima humana divinitati assimilatur, vid. ipso intclligere." 16 De retributionibus sanctorum, O p p . I, p. 316: "Ibi ( in patria) cessat omnis principatus et dominatio, excepta dominatione ejus, qui est Dcus."
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proper places, they are hindered from the expression of their own natures, and are under coercion. T h u s it is manifest to you that no natural body can, even for a short time, be detained outside of its natural place except by violence; natural bodies, however, are related to their places analogously to the relation between spiritual substances and their ends. F o r just as bodies naturally seek their places, and come to rest in them most peacefully, free f r o m all local motion, and do this naturally; so spiritual substances seek their natural ends, and it is not possible for them to come to rest short of them, or to be detained even for a short time. 1 7
It is obvious from this that William is not an indeterminist. The will has its natural end, the good, to which it is formally determined; the major premise of every practical syllogism is given in the very nature of the soul—i.e., the good is to be sought, and evil avoided. Since every voluntary choice involves an intellectual act, and since the intellect understands in terms of contraries, the soul cannot be formally determined to either of the contrary possibilities of action that are presented to it bv the intellect. William also recognizes the freedom of the soul to act or not to act in any given instance; 18 that is to say, although the soul has the power at any time to consider its actions in the body intellectually and morally, it can also let the bodily passions take their course if it chooses to refrain from bringing them before the high court of the will. It is outside the scope of this essay to consider William's moral philosophy, but it may be said that his understanding of human conduct and motives is considerable. He shows a keen appreciation of the close relationship between the psychical and the physical, stressing the fact that one good decision does not make a virtuous man. Right action must become a habit of the inferior motive powers of the soul, or, as we should say, of the body, before virtue is established in the man. The first principles of right conduct are naturally present to the soul. William refers to them frequently as synderesis, or as regulae honestatis, or as the natural law implanted in the soul. These rules of ritrht conduct are in the intellectual part, not in the affective part; 17 18
De an., p. 146. De Un„ p. 788: "Libertas est super operari et non operari." 88
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they are "the splendour of the natural law, or the intellectual faculty insofar as it is illumined by the light of natural law." 19 Conscience, which some had distinguished as a separate faculty of the soul, is considered by William to be nothing other than the intellect itself: it must, he says, be either knowledge, belief, or opinion, which are the three natural types of cognition. It is not the same as synderesis; rather it is the knowledge of the Tightness or wrongness of particular actions which comes from judgment in accordance with the principles of synderesis.20 The problem of freedom of the will does not cause William of Auvergne much concern, though he argues against determinism occasionally, especially in connection with the Arab doctrine that God produces the intelligences of necessity, and that the movements of the celestial bodies determine human actions. Also, in discussing the sacrament of penance, he paints a vivid picture of the testimony of conscience whereby man accuses himself of sin, knowing in his heart that he sinned freely and of his own will.21 The freedom of the human will, according to William, is self evident, it is known by every man through "the very presence of the truth" in him, and is in practice admitted by the whole world. Nearly all human activities, institutions, habits, and beliefs presuppose it. If there were not freedom, says William, "there could be no discipline or correction, no education, nor would ethics, and virtues and vices, be discussed by men any more than they are discussed by stones." 22 W e do not have to demonstrate freedom, for its presence makes demonstration superflous. Tully rightly said that reason is a kingdom of the soul conferred by divine nature. For nature herself teaches us this. The order of natural jus19 De an., p. 220: "nec aliunde potest contradicere vel remurmurare vis intellectiva semper, et sine errore malis operibus, quam ex illo splendore seu lumine quod in ea naturaliter splendet ex irradiatione etiam verae ac luminosissimae veritatis . . . synderesis nunquam errans, et nunquam cessans a contradictione et rebellione malorum, non potest esse vel dici in anima humana nisi splendor iste legis naturalis, aut vis intellectiva in quantum splendet lumine hujus legis." C f . De legibus, O p p . I, p. 20: " L o c u s igitur proprius regularum honestatis . . . intell e c t s est." 20 De an., p. 221: "nihil igitur quidem conscientia in anima humana nisi aliquid istorum trium" (scil. knowledge, belief, opinion). Ibid., p. 220: "manifestum est conscientiam vim naturalem nullo esse m o d o r u m . " 21 Tractatus Novus de Poenitentia, O p p . I, pp. 571-572. 22 De Poenitentia, O p p . I, p. 455.
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tice teaches us to warn those who injure us that they should repair the injury; that is, to ask them first to show justice of their own accord, as judges of themselves, for nature herself has taught us that they should be responsible for their actions. When however they refuse to give us justice of their own accord, nature herself teaches us to appeal the case (causam deferre) to superior authorities. For justice and every virtue, as Aristotle testifies, is more certain and better than any art.23 The presence of the natural law in us, or of synderesis, is like a letter signed and sealed by the divine authority, which delegates the authority and responsibility of conduct to us, making us judge of our own actions, while reminding us perpetually of the norms by which we ought to act, and by which we cannot help judging our actions. Thus you see a man exercising within himself all the parts of judgment concerning thoughts of evil, accusing himself, as if he were constituted as prosecutor against himself, and setting forth, as his conscience reminds him, those things which are against him. His own thought bears witness against him with respect to those things, while the evil itself, rising up from the circumstances recounted, and as if reading the sentence against him, condemns him in his own judgment and justifies God. Thus the case is judged, while as if with a sword of grief and a club of indignation he probes into himself, revealing himself as his own tormentor, and he seems to order the sentence which has been brought against him to be executed, and he becomes the executor of his own sentence against himself. And all these things which he does to himself he reads in the letters commissory of his delegated authority (i.e., synderesis), and knows the judgment of his damnation that has been brought against him.24 A further argument against determinism is found in the very nature of the will. Though it is obvious that we are not always able to carry out our decisions, due to physical violence or insurmountable impediments, there can be no direct coercion of the will itself. The passions, such as fear or hope, may influence the will in its decisions; but the fact remains that it is the will which makes the choice, and that where there is choice there is freedom. Such is the liberty of the human will, that it does not suffer itself to be coerced in its proper act, which is to will, nor to be prohibited from it Tractatus Novus De Poenitentia, Opp. I, p. 571. Tractatus novus de poenitentia, Opp. I, p. 572: "Judex sui ipsius ex divinae auctoritatis delegatione cognoscitur homo." 23 24
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except by consent—that is to say, except when it wills this. For let us suppose that it is forced unwillingly to will something, and let this object be called A; according to this situation, then, the subject (i.e., soul) himself wills A, against his will, and he wills the thing itself that is willed. Hence he wills this volition A, and wills it chiefly on account of A, since the volition is for the sake of what is willed; thus he wills A, and not unwillingly, and therefore he wills it neither under coercion nor against his will. In the same way I say that he cannot be prohibited from willing A, if he wishes to will A . . , 25 T h e above argument appears several times in William's writings. It does, of course, presuppose that human actions are willed, and only serves the purpose of showing that if an action is voluntary, it is free and not the result of coercion. T h e fact that some human actions are voluntary is taken as self-evident; the presence in us of an interior principle of voluntary action is a first principle, and is beyond demonstration. Some, however, granted this, but believed that the motions of the heavenly bodies determined not only the motions of the material elements on the earth, but also the human will in its decisions. The human will does not incline to anything by violence or necessity, as I said, but by counsel or persuasion, by hope and fear and other passions, and even then only willingly and through apprehension or apprehensions. But from the motions of the heavenly bodies no apprehensions come to it, but rather they come from things (unless perhaps one is considering the planetary motions themselves), and concerning voluntary matters no apprehensions come to it from them. Therefore our wills derive no inclinations from motions of this kind. But our volitions come from the inclinations of our wills—that is, our actions, and those things which follow from them, or which happen because of them.26 For William, as for most other Scholastics, freedom does not involve the emergence of something from nothing—voluntary actions are caused, and do not simply appear. T h e point at issue is whether human actions are caused by human souls, through an act of intelligent choice, or whether they are determined externally by circumstances and by the events which we call contingent. It is not so much a lack of understanding of the human will, as a lack of understanding of the 25
De Un„ p. 786. 26 De Un., p. 786. 91
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nature of causality, and of necessity and contingency in nature, that makes people deny the freedom of the will; and even then, their denials are verbal only, since in their own actions they cannot but presuppose their freedom. Inexperienced men, says William, say that the cause of combustion is the man who applies fire to the wood, or who puts wood on the fire. Or they say that the cause of the collapse of a building is the removal of a pillar, meaning that this is the efficient cause of the motion. If, however, they had a deeper understanding of the nature of causation, they would see that the efficient cause of the building's collapse is its weight, and that the removal of the column is not a cause at all, but merely a favorable circumstance aiding the cause (i.e., the weight of the edifice) in its operation, by removing an impediment to its natural motion.27 In the same way, the only efficient cause of a voluntary action is the will of the person who performs the action. Ignorance, sloth, attachment to pleasures of sense, etc., can be impediments hindering the will, but their presence does not rob the will of its authority and freedom, any more than the presence of the column robs the building of its weight. The motions of the stars do not have even this much influence on the will, since they are neither impediments nor causes of the removal of impediments to voluntary action, unless one were to say that the sun, by its luminosity, aided our voluntary operations insofar as their performance required the act of seeing28 In this way William argues against the external determination of events by appealing to the Aristotelian doctrine that in natural things the immediate cause of action is the substantial nature of that which 27 Ibid., p. 787: " N e c moveant te sermones vulgarium hominum, et rationes causalitatis ignorantium, qui causam combustionis dicunt, vel ilium qui ligna applicat igni, vel ignem lignis, aut alii combustibili. Similiter dicunt homines impend, qui subtrahit columnam aedificio, vel suffodit fundamentum illius, causa est ruinae ejusdem, et re vera causa quaedam est, non autem efficiens, immo ponderositas aedificii causa est efficiens casus ipsius, qui est motus naturalis in deorsum, cujus principium naturale et efficiens ponderositas est; hujusmodi causam vocaverunt nonnulli causam sine qua non fieret ruina aedificii, et revera non est causa in aliquo genere causarum . . . sed est de his quae dicuntur adjuvantia causas ipsas, vel tollendo impedimentum prohibens eas operari, vel praestando aliquid, quo causa ipsa indiget ad hoc ut sit operans in effectu." 2 8 De Un., p. 787: "In motu autem coelesti, et voluntariis actionibus . . . nec etiam possibile est fingere hujusmodi adjumenta, nisi quis forte dicat quod Sol luminositate sua adjuvat voluntarias operationes nostras . . . in quibus actus videndi requiritur."
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acts—actions are determined by the natures of the things which act, and though the presence or absence of the proper external conditions may determine the possibility or impossibility of the action taking place, it is the nature of that which acts that determines the action itself, if the action takes place at all. William pursues this subject further, arguing against those who state that the presence of the proper conditions for an action determines and necessitates that the action take place, and who conclude from this that temporal and spatial occurences follow each other according to an inflexible and determined order. Some held that the First Cause is just as determined to produce the first effect as the latter is determined to the production of its effect; but such a view supposes that the First Cause is not first, but is subjected to a prior necessity. If it were said that from the first cause the first effect flows immediately by necessity, then it would follow that it proceeds from the first cause either by nature (per modum naturae) or by will; but concerning the way of nature you know already that it is far from the nobility and glory of the creator, since, as you have learned from Aristotle, nature operates according to the manner of a servant, and therefore servilely. . . . It is not permitted to nature not to do that which it naturally does, nor is there in nature power or liberty, or choice of doing and not doing. 29
But the fundamental error of the determinists, according to W i l liam, is their failure to distinguish between material necessity and formal necessity, and between necessity which is found in science, and the contingency of particular existences and events. Such people argue that if there is found a concurrence of ( 1 ) the will to write, ( 2 ) the opportunity to write, which would include the presence of the needed materials etc., the writing takes place necessarily. T h e y then reason backwards from this concurrence of events, and hold that each component was itself the necessary result of a similar concurrence, and so on to infinity. According to this view, says William, every singular existent or occurrence is necessary. 30 In my youth this reasoning led me sometimes to believe that no singular contingent events had a cause of this kind, or one or more causes joined 29 De Vn., p. 78730 Ibid., p. 789: "Hujusmodi autem exemplum est, quia cum in aliquo concurrerint scribendi voluntas, et opportunitas, caeteraque omnia quae requiruntur ad hoc, ut potentia scribendi exeat in actum, exibit necessario in actum. . . . Qua de causa cujuscumque singularis vel existentia, vel eventus erit necessarius."
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together such that, they being present, the result would necessarily follow. . . . Now however you may know that it is perhaps true, that when an aggregation of causes of this kind (that is, of an efficient cause, and of those aids or conditions required for its operation) is present, it is necessary that there should be a beginning of the operation or event; not however the event itself, or its completion, and I am speaking here of those things which are generated or which take place through temporal succession. Thus it is necessary that from the concurrence or aggregation of the efficient cause and of all the conditions requisite for its operation, as I said, the event or operation should commence, or make a beginning; and since for its completion or consummation the stability of this whole concurrence is necessary, then, if these conditions are fulfilled, the consummation will follow. However, since the stability itself (of these conditions) is not stable by any necessary stability—nor is it possible that this should be the case—it is not necessary that from the aforesaid aggregation the consummation should necessarily follow, and for this reason it is not generally true in things of this kind, that from the concurrence of conditions the consummation of the event should follow, unless the unchanging permanence of these conditions is also taken for granted.31 Thus, for William, freedom of the will is shown to be possible on the basis of the fundamental Aristotelian distinction between logical necessity and natural contingency, or on the basis of the Peripatetic restriction of science to the universal. Freedom, again, is shown to belong to the human soul by an appeal to introspection, to habits of thought and action on which human life and human institutions are based, and which no man is able to deny in his heart. W e have seen, further, that William is not an indeterminist—man is free to choose between possibilities of action, but his will is formally determined to make its choices under the aspect of the good, and he is not free to contradict the first principles of the practical intellect in his "interior reason," nor to deny his responsibility for voluntary actions. T h e autonomy of the will, for William, is not unrestricted; it is a delegated authority, which constitutes the soul as judge of its own actions, but insofar as it judges them it is bound to do so by the first principles of the practical intellect, which it receives from God, as the light of the natural law in the human soul.
31 De Un„ p. 789.
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William of Auvergne 2 In defending the immortality of the soul, as in his defense of its freedom, William of Auvergne appears not so much in the role of an inquirer after truth, as in the guise of a defender of civilization and morals. Like many others before and after him, William stands aghast at the thought of any attempt to subtract from the scheme of universal justice the sanctions which give it practical strength. If death ends all, he reasons, what is to prevent, beyond mere temporal expediency, crimes and immorality? Heaven and hell are required for the fulfillment of justice; and if heaven and hell are to be populated with human souls, these souls must survive the corruption of their bodies. It is obvious from these things that divine justice, if it is living and true, must result in judgment, nor can it be kept from this by ignorance, or impossibility, or by the difficulty of doing what is just. Since therefore in this present life the justice of God does not result in a complete judgment— for innumerable wicked ones here receive nothing but good, while innumerable virtuous ones here suffer only evil—; it is necessary that in another life a return, or retribution, should be accorded through this justice to each account.32 Other theological arguments are also set forth. T h e goodness of God, as well as His mercy, are guarantees of the immortality of the soul. T h e creator not only made all creatures good, insofar as they have being, but created for them goods appropriate to each kind of creature—corporeal goods for corporeal things, and spiritual benefits and felicity for spiritual creatures. Since man is naturally capable of enjoying greater good than is attainable in this brief earthly life, and since the divine goodness flows into all creatures to the extent of their capacity for receiving it, it must be concluded that the death of the body, in the creator's intention, does not mark the end of the soul. 33 Furthermore, though it is true to a certain extent that virtue is its own reward, surely, says William, so noble a being as G o d would not limit his rewards to the faithful so narrowly; rather, it befits the good32 33
De an., p. 185. De an., pp. 177-179. 95
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ness and largesse of the creator to reward his servants more lavishly than they have the right to demand. Y o u may know evidently that since human souls are naturally assimilable to the creator, by immortality and felicity, though in proportion to their inferiority and order and congruence, it is necessary that the divine goodness should extend its munificence and largesse with respect to them (souls) to the extent that it would create them naturally immortal. 3 4
Similarly, to deny the immortality of human souls is equivalent to detracting from the glory of God. 3 5 Beyond this, the resurrection of the dead, as in the case of Lazarus, as well as the sublime testimony of the saints and prophets, give us experiential evidence of the soul's immortality. 36 Indeed, it is universally recognized that prophets, when in a state of prophetic ecstasy, are almost separated from their bodies; but since in this state they are far more alive spiritually than at other times, it seems that the more the soul is out of the body, the more alive it is.37 Such are the arguments with which William supplements the more philosophical proofs of immortality inherited from the ancients. These latter may be divided into three groups: ( 1 ) Arguments to show the independence of the soul from the body; (2) Arguments based on the nature of the soul as principle of life; (3) Arguments based on the intellectuality of the soul, and its capacity for attaining intellectual perfection and for enjoying beatitude. That the soul is independent of the body, and superior to it, is known by introspection. It is evident that the soul gives life to the body, and not vice versa, as any unbiassed person will testify. W i t h o u t doubt he will say to you, M y body lives from me, not I from m y body; and for this reason m y life depends in no w a y on the life of m y body, but rather it depends on me, as the light of the sun does not depend on the light of day, but rather the contrary; for just as the daylight is nothing but the irradiation of the sun in the air, so the life of the body is nothing but the irradiation from me into it. 3 8 Ibid., pp. 181-183. Ibid., p. 189. 38 Ibid., pp. 189-190. 37 Ibid., p. 192: "evidenter et magis vivant in statu rapnis, quam in statu contrario." 38 De an., p. 147. 34 35
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It is of course true also of animal souls that they give life to their bodies, yet no one, William admits, considers animal souls to be immortal. The reason is that animal souls exercise no functions apart from corporeal organs, so that immortality for them would be empty and useless. But the fact that human souls exercise some functions without the mediation of the body is one of the best reasons for believing it to be immortal. T h e human soul, however, has its most sublime and principal powers and operations apart f r o m the body, that is, not bound to the b o d y nor in any w a y subject to it, but freely and immediately, without the aid or ministration of the body, it exercises these powers, and carries through and completes operations of this kind. Of these operations y o u have, off hand, several examples, such as thinking, meditating, contemplating, investigating, and the enjoyment of spiritual and sublime goods, grief over the contrary evils, and of these none pertain to the body. 3 9
Aristotle himself recognized the independence of the soul with respect to its intellectual faculty; but in saying that only the intellectual part of the soul is immortal, Aristotle committed the stupid blunder of thinking that a spiritual subsance like the soul can be composed of divisible parts.40 Since, however, the soul is immortal insofar as it is intellectual, it is necessarily immortal as a substance. It is likewise evident that the human soul differs from brute souls in that it is free to resist its bodily passions, which indicates its natural independence of the body. 41 Furthermore, says William, who ever thought that an occupant of a house depended for his being on the house? What pilot depends for his existence on his ship? What citherplayer on his cither? Since where the act is, there also is the power, and since the act of seeing belongs neither in whole nor in part to the eye, then neither in whole nor in part does the power of seeing belong to it; hence it is entirely in the soul,
Ibid., p. 147. De an., p. 162: "Non intelliget homo iste in hoc quia Aristoteles dicit partem animae speciem animae, quod indubitanter verum est, sed partem potius quae sit de totalitate et integritate animae ipsius. Iste autem intellectus non solum erroneus est, sed impossibilis." 41 Ibid., p. 148: "anima rationalis est supra ejusmodi passiones jure ac lege naturae, animae vero irrationales sub eis sunt." 39 40
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and it does not perish when the eye perishs. . . . Therefore, just as the power of sight does not perish when the eye perishes, so the soul does not perish, either in whole or in part, when the body perishes.42
Plato's argument from the contrariety of life and death is given by William: just as whiteness in a body cannot itself become black, even though the body may, so the soul, which is principle of life in the body, cannot in itself receive its contrary. And I think that this was the intention of Plato in his book which he wrote concerning the immortality of the soul, which they call the Phaedo, wishing there to establish the immortality of the soul, he took this stand, that what moves per se moves forever, meaning by motion life, just as life (for a body) consists in being moved. His words would, however, be absurd if this motion were understood as continuous and corporeal motion, as Aristotle declared in his book of physics. My interpretation, moreover, is attested by the saying of Avicenna where he says that the soul is the first motion and first emanation to proceed from the creator. 43
It is evident, says William, that if the soul receives its life from another, and is not, as Plato seems to have held in his argument from contraries, the principle of its own life, then the source of the life of the soul must be as superior to the soul as the latter is to the body, to which it in turn gives life. But it has been shown, says William, that death results not from a drying up of the soul's life-giving power, but merely from the cessation of receptivity to life on the part of the body. Hence the soul would, of its own nature, be a principle of unending life for the body if the latter were not corrupted. Therefore it is all the more likely that God, from whom the soul receives its own life, will be as ready to give perpetual life to the soul as the soul is ready to give it to the body.44 The facts of experience support the view that the soul is more healthy and alive apart from the body than in it; for as the body wastes away, especially in the practice of asceticism, the soul grows stronger; and the "human soul naturally grows young as its body grows old."45 Further, wounds which mutilate the body leave the soul «ibid., p. 149. 43 Ibid., p. 170. 44 De an., p. 170. 45 Ibid., p. 163. 98
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whole; therefore death, which is the complete destruction of the body, should not affect the soul's life. 46 Further evidence of the soul's incorruptibility is found in the fact that while the sense organs can be destroyed b y their proper sensibles when these are violent and not proportioned to their receptivity, the intellect is not destroyed nor weakened, but rather strengthened, b y extreme intelligibility. "It is manifest that the vehemence of the intelligible or spiritual light not only does not weaken the intellect, but comforts and clarifies it." 4 7 T h e first cousin of this argument, the argument based on the fact that the intellect understands through contraries and can therefore receive contrary intelligibles at the same time, being thereby immune to destruction through contraries, is not explicitly mentioned by William. T h e arguments which seem most convincing to William are those which reason from the natural capacity of intellect and will for unlimited knowledge and good, to the natural possibility of these ends being attained. T h e soul, he says, is naturally capable of knowing all truth; but knowledge has no limit, nor has wisdom or the good any limit. Hence, since the soul cannot achieve its natural infinite perfection in a finite time, it must be naturally immortal. Therefore the human soul is naturally capable of an infinite or perpetual existence; and a natural potentiality or natural capacity cannot by nature be perpetually and universally deprived, by necessity, of its actuality. . . . For nothing is as necessary to the human soul, or to any other creature, as its existence, conservation, and completion. 48
T h e movement of any substance is, naturally, toward its end; but if its end is unattainable, this natural motion is in vain. But nature does not act in vain, or for ends impossible of attainment. Hence, since the movement of the soul is toward infinite knowledge, whose attainment demands infinite time, the soul must be naturally immortal. 49 Again, the desire for unlimited knowledge is a disposition of the soul; but a 46 Ibid., p. 160: "Si enim ad experimenta intenderis vel intendere volueris, invenies in corporibus mutilatis, et magnis atque nobilibus membris suis detruncatis, animas integerrimas atque fortissimas tanquam si interius suppletum esset eis quid ex defectu membrorum eisdem sublatum vel ablatum videbatur."
« Ibid., p. 171.
«Deaw., pp. 153-154.
«Ibid., p. 156.
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disposition cannot have a greater potential end than the substance in which it inheres; therefore the soul, as a substance, must have an existence proportionate to the potential perfection of its disposition.50 Furthermore, the natural locus of the intellect is in knowledge of God, in the union of the intellect with what is most intelligible; but since this is its natural end, it cannot be kept from it, either voluntarily or by violenc, by any created being.51 Very much the same type of argument is advanced with respect to the soul's capacity for the enjoyment of spiritual goods. The fact that we are always discontented with sensible and worldly pleasures or riches indicates that the soul is naturally intended to enjoy spiritual goods, and most of all God himself—inquietum est cor meum donee quiescat in te, in the words of St. Augustin. The pleasures of the body are never satisfying to the soul, which on the contrary yearns to be free of its earthly tomb. The fact that this is never the case with animals indicates a different destiny for man, and that the natural inclination of the human soul is toward an end distinct from that of its body. 52 T r u l y the death of the human body, especially in this state of misery and mortality, is not only not a part of the misery of human souls, but is their liberation from innumerable great miseries and from the captivity and imprisonment in which, bound to their bodies, they are detained while they live in them. . . . In the natural state of health, liberty, and purity, however, it is far otherwise, as it was also at the beginning of human creation, and as it will be in the future resurrection, at least with respect to those who are to be saved and glorified; for then human bodies will not be prisons to pious souls, nor burdens, nor the cause or occasion of any misery. 53
William's Platonic leanings, which occasipnally seem almost Gnostic or Manichaean when he speaks of the body in this life as a prison or tomb of the soul, are restrained, and kept from leading him into a moral dualism of spirit and matter, by confining the picture to the soul and body in this life, and by assuring us of the intrinsic goodness of the body in the natural state of purity, when the body serves 50 Ibid., p. 158. si Ibid., p. 173. 52
53
De an., pp. 166-168.
Ibid., p. 169. 100
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the soul without defect or rebellion. With his essentially Platonic conception of the soul as a distinct substance temporarily joined to the body, the doctrine of immortality fits fairly easily into William's system; the arguments he advances are like a review of the different topics previously dealt with, and they reveal the fact that one of the dominant influences guiding William's analysis of the soul, with respect to its definition, relationship to the body, and intellectual capacities, was the doctrine of immortality which the system supports so well. Like Augustin, William of Auvergne is interested chiefly in God and the soul—Deum et animam scire cupio, Nihilne plus? Nihil omino 3 It is scarcely necessary to state, by way of conclusion, that William of Auvergne's psychology is thoroughly Augustinian in inspiration and spirit. It was perhaps inevitable that this should have been the case, in view of the fact that William was primarily a Christian theologian attempting to uphold views concerning the soul that were deeply imbedded in the Christian tradition, amidst a great mass of philosophical doctrines derived from pagans and infidels. The first instinct of the apologist, when confronted by new arguments and questionable doctrines, is to sift them, and where necessary try to refute them, by the principles and premises which are familiar to him. Only later does he catch his breath sufficiently to consider the possibility of defending his own conclusions by his opponents' principles, and of revising his whole system accordingly. William's definition of the soul, as an indivisible spiritual substance inhabiting and vivifying a quasi-alien body, is essentially Platonic. Having started with this definition, it is natural that he should carry much of the Platonist and Augustinian point of view into his discussion of the various functions of the soul—movement, sense-perception, and intellectual knowledge. The substantial distinction between soul and body, involved in this definition, entails a use of God in the explanation of knowledge that is likewise typical of the Augustinian tradition; for if the soul is a spirit that does not share with its body the give and take of the corporeal world, it must acquire its knowl54
St. Augustin: Soliliquia, I, ii, 7.
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edge from some source other than the material world in which its body lives and breathes. It must have an inner light, implanted in it and kept aflame by a Wisdom that is not of this world. The world of intelligibles, which is for William nothing other than the divine Word, is the true and natural home of the human intellect, immediately present to it by its inner light, and only obscured in this life by sin and attachment to sensible things. The Augustinian doctrine of an intellectual light, coming to the soul from God, is almost inevitable, in some form or other, once the soul is defined in Platonic fashion. The senses then become hindrances to the full development of this inner light in the soul, and distractions which lure the soul away from its true home, drawing it downward from the contemplation of the eternal Wisdom to an inferior realm of opinion, of shadows, or of "confused ideas." Such a situation, which William considers unnatural for a substance created with such nobility and dignity as the soul possesses by nature, demands an explanation, for it would be strange if a soul capable of contemplating the truth in its purity would voluntarily turn away from it. Plato suggested a primordial fall of souls to explain their imprisonment in bodies; the Christians fell back on the doctrine of original sin. William of Auvergne makes extended use of this explanation, to account for our defective mode of knowledge, the conflict between our higher aspirations and the earthly drag of the senses, and the vast difference between what man is and what he ought to be. T o push the problem back into the very dawn of creation, as Plato does in his myth, or as Christianity does in its vast epic of sin and atonement, is to push it out of the sphere of philosophical explanation, and into the realm of theology. T o the Augustinian, however, the fundamental mysteries of theology are too important to be overlooked, even by the philosopher; and the doctrine of original sin, like the presence in man of liberty and moral responsibility, is a principle of explanation which is itself beyond the reach of explanation in other terms. Augustinian also is William's fondness for the distinction between wisdom and science, between the knowledge which tastes and participates in the inner nature of its object, and the knowledge which is, in comparison, only a bare skeleton of reality. Like many contemporary philosophers who rebel against "static abstractions," William wants a "living truth," a kind of knowledge that is not mere knowledge, but something as intimate and satisfactory as self-consciousness. 102
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But if there be such a superior wisdom to be had, men should seek it with all their power, and should hold all inferior modes of knowledge as of little account in comparison. It is better, from the Augustinian point of view, to forego the vain satisfaction that is afforded when we stop in via to enjoy merely human sciences, and to seek to attain the true light by means of faith and good works, than to cut ourselves off by resting content with what we possess. Hence the Augustinian tendency to emphasize the superiority, in this life, of a good will over a good intellect—a tendency that is also noticeable in William. It would seem, from this account, that William of Auvergne was a Platonist or Augustinian in all respects, and that Aristotle had no influence on him whatever, except by way of supplying a different terminology and new matter for criticism. This is true to the extent that William's acquaintance with Peripateticism did not result in making him into a Peripatetic—at least not in his psychology; but it would be inaccurate to say that Aristotle did not exercise an important influence on William. This influence is to be discovered in numerous elements and characteristics of William's philosophy. For one thing, William did accept the Aristotelian physics in its main outlines, adding it on to his Augustinian conception of the twofold world of spirit and matter. Since, in the Augustinian tradition, corporeal things are unable to affect the things of the spirit, none of the vital doctrines of Augustinian could suffer from adopting the Aristotelian explanation of the corporeal world, and of change and motion, provided that the principles used in physics were restricted to the corporeal world. Thus, in William of Auvergne, we find that the human body is a perfectly good Aristotelian composite of matter and form, equipped with Aristotelian sense organs in potentiality to their respective types of contrariety, while the soul remains Augustinian, a spiritual substance moving the body without being the substantial form of the body. The doctrine of the plurality of forms, which is an Augustinian use of an Aristotelian principle of explanation, was not developed to any extent by William, but the foundations for it were laid. As this doctrine is developed by Bonaventura and other thirteenth century Augustinians, it constitutes a new expression of Augustinism, whose development may be attributed in large measure to the influence of Aristotelian science. Thus, while thirteenth century Augustinism is not Aristotelian in its point of view nor in its basic principles of ex103
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planation, its way of stating the Augustinian position is largely due to Peripatetic influence. The scientific tendencies of the later mediaeval Augustinism (if not, indeed, of a large part of modern philosophy) were probably due in large degree to the influence of Aristotle, which induced the Augustinians to develop a philosophy of nature, equivalent in range and subject matter to the Peripatetic system, in accordance with their own principles. Another influence of Aristotle on William of Auvergne is revealed in the recognition by the latter of a certain independence of philosophy, with respect to its method, from theology. William frequently argues from revelation, but invariably goes on to prove his point by "unshakeable demonstration" such as may convince those who do not accept Christian revelation. This was not of course a new distinction, but in William of Auvergne there is more appreciation of the possibility of constructing a vast synthesis of philosophy and theology, in which each science retains its autonomy of method, in harmony with each other. There are places, in William's philosophical writings, where he is unctious and filled with a pious enthusiasm that seems out of place in a philosopher; but for the most part he writes with a praiseworthy restraint, seeking to make his appeal to reason and experience alone. Aristotelian logic was of course well established among the scholastics at the time William wrote; but it might be said that the Stagirite influenced William in his methods of discussion and analysis, keeping him from using analogical reasoning on all types of subject matter, and from regarding the corporeal world as being merely a symbolic image of the Trinity and of divine purposes. Things participate only in such transcendental ideas as Being, Wisdom, Goodness, etc. with respect to specific essences; the truth of things is in the things, or in their adequation to the intellect. Possibly the development of universal analogies, as found in Bonaventura, is more consistent with the basic Augustinian position; but in any case, William of Auvergne had a sufficient appreciation of the Aristotelian metaphysical position, in its relation to logic, to restrain himself in this direction. Probably the point at which William was most directly influenced by Peripatetic philosophy, in his psychological doctrines, was in his discussions of the theory of the active intellect. Here, as we have seen, he was very much concerned to find, in his Augustinian framework, an equivalent of the Aristotelian explanation, or of the pseudo-Aris104
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totelian explanation developed by the Greek and Arab commentators. By regarding the first principles as innate ideas, or a priori truths and rules, implanted in the soul by its Creator, and by rejecting the doctrine of abstraction which is so fundamental to the Aristotelian psychology, William was able to dispense with the active intellect. But although he rejected the theory that our knowledge of the first principles comes through experience, William saw the necessity of accounting, in some way, for the close connection between human sense activities and the development (in a material sense) of intellectual knowledge. This led him to develop his theory of occasionalism, and of the habitus scientiarum, which he linked up with the distinctions of the intellect that had been developed by the Greek and Arab commentators. Thus the Aristotelian influence did not cause William to depart from his Augustinism, but it did cause him to develop it in terms that brought the two psychologies closer together on a common ground of discussion, revealing more clearly the problems to be solved, and the differences in the Aristotelian and Augustinian ways of solving them. In this way William may be said to have done important preliminary spade-work both for the later Augustinism and for the later Peripateticism. Whether William of Auvergne can be justly called a philosopher, and not merely a theologian, will depend on whether a philosophy that is at the same time a theology is, properly speaking, philosophical. By the test of subject matter, William is primarily theological in his interests, though from his own point of view the distinction in subject matter between theology and metaphysics is a false one. On the other hand, he is not a theologian in the narrow sense of one who argues purely from authority and revelation; and he is a philosopher in the sense that his system is meant to do all that a philosophy can do, and to give an adequate picture of the universe. It is, in fact, precisely this desire for adequacy that leads the Augustinian to consider theology a necessary basis for philosophy; a metaphysics that is not a theology is, to the Augustinian, inadequate and unsatisfactory, and a philosophy that makes no appeal beyond experience seems to him blind, uncertain, and erroneous.55 5 5 The sort of criticism which Descartes levelled at Scholasticism, whose principal note was the uncertainty of its principles, is similar to the Augustinian mistrust of Aristotelianism and its empirical tendencies. The fallibility of the senses is the war-cry of the Augustinian, who offers as refuge unshakeable a
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William of Auvergne's significance in the history of philosophy is that of a transition figure. He was one of the first to attempt to assimilate the new Greek and Arab philosophical literature to the Augustinian framework, and in many respects the system which he developed, despite its rather piecemeal construction and its occasional confusion, remained the basis of the later expressions of Augustinism. Some of his doctrines, such as the real distinction between essence and existence, and his definition of spiritual substances as subsistent forms, became important elements in the Thomist system also. But like many transitional philosophers, William of Auvergne is obscured by the shadow of the greater thinkers who followed him, and who built on foundations which he did much to lay. In comparison with the expositions found in Aquinas and Bonaventura, William's philosophical writings seem confused and even inconsistent; but if this rather unjust standard of comparison be omitted, thé coherence of his thought, and the comparative order which he brought out of what must have seemed a chaos of philosophies, can be appreciated. priori principles, seen "clearly and distinctly" or innate in the human mind, which will give philosophy a foundation as firm as that of geometry. William of Auvergne was, in important respects, a Cartesian—or Descartes was an Augustinian!
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BIBLIOGRAPHY A. Writings of William of Auvergne Citations from the writings of William of Auvergne, in this essay, are from the Orleans edition of 1674, edited by Blaise Leferon: Gulielmi Alverni Opera Omnia. This edition is in two folio volumes: Vol. I is paged 1-1074; Vol. II is in two parts, the first of which contains inauthentic sermons, while the second part, called Supplement to Vol. II, is paged 1-248. All references to Vol. II are to the Supplement, or second part of the volume. For convenience, references to the De Anima (Opp. II, Suppl.) and to the De Universo (Opp. I), will be abbreviated De An., and De Un., respectively. References to other treatises by William of Auvergne will be given with the full title of the treatise, and the volume in which it appears in the Orleans edition. B. Studies on William of Auvergne Baumgartner, M. Guttmann, J. Kramp, J. Landgraf, A. Landry, B. Schindele, S. Valois, N. Werner, K.
Weser, J.
"Die Erkenntnislehre des Wilhelm von Auvergne" in Beitraege zur Geschichte der Philosophie des Mittelalters, B. II, Hft. 1, Munster, 1893. "Guillaume d'Auvergne et la littérature juive" in Revue des études juives, t. 28, Paris, 1889, p. 248 fï. "Des Wilhelm von Auvergne Magisterium Divinale" in Gregorianum, I (1920), 538-584; II (1921), 42-78; 174-187. "Der Traktat De errore Pelagii des Wilhelm von Auvergne" in Spéculum, 1930, pp. 168-180. "L'originalité de Guillaume d'Auvergne" in Revue de F histoire de la philosophie, t. 3, pp. 441^65. Beitraege zur Metaphysik des Wilhelm von Auvergne. Diss. Munich, 1900. Guillaume d'Auvergne, évêque de Paris, sa vie et ses ouvrages. Paris: Picard, 1880. 383 pages. Wilhelms von Auvergne Verhaeltniss zu den Platonikern desXlllten Jahrhunderts. Vienna, 1873. Die Psychologie des Wilhelm von Auvergne. Vienna, 1873. "Das Absolute in seinem Verhaeltniss zum Gewordenen nach Wilhelm von Auvergne." in Philosophisches Jahrbuch 1917, pp. 302-312. 107
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C. Works Relevant to William of Auvergne and his Times Excerpta e libro Alfredo Anglici De motu cordis item Costa-ben-Lucae De differentia animae et spiritus. Innsbruck, 1878. Die Pseudo-Aristoteliker Schrift ueber das reine Bardenhewer, O. Gute. Freiburg, 1882. (The Liber de causis.) "Die Philosophie des Alanus ab Insulis" in Beitraege Baumgartner, M. zur Geschichte der Philosophie des Mittelalters, B. II, Hft. 4. Munster, 1896. "Des Domenicus Gundissalinus Schrift von der UnBiilow, G. sterblichkeit der Seele," in Beitraege zur Geschichte der Philosophie des Mittelalters, B. II, Hft. 3. Munster, 1897. Récherches critiques sur l'âge et rorigine des traducJourdain, A. tions latines d'Aristote. 2d ed. Paris: Joubert, 1843. Lecoy de la Marche Anecdotes d'Etienne de Bourbon. Paris, 1877 (references to William of Auvergne are on pp. 388-389.) Maimonide. Paris, 1911. Levy, L. G. Da Guglielmo d'Auvergne a San Tomaso d'Aquino. Masnovo, A. 3 vols. Milan, 1945. (Portions of this work appeared in 1930 and 1934). Minges, P. "Philosophiegeschichdiche Bemerkungen ueber Philipp von Greve," in Philosophisches Jahrbuch (1914), 21-32. Averroès et l'Averroisme. 3d ed., Paris, 1866. Renan, E. Autour du décret de 1210: Alexandre d'Aphrodise Thery, G. (Bibliothèque Thomiste, VII, Kain, Belgique, 1926). Barach, C. S.
D. Collections of Documents and Extracts from Manuscripts Denifle-Chatelain Hauréau, B. Institut Impériale de France Plessis-d'Argentré 108
Chartularium Universitatis Parisiensis, t. I. Paris: Delalain Freres, 1889. Notices et extraits de quelques manuscrits latins de la Bibliothèque Nationale. 6 vols., Paris, 1890. Notices et extraits des manuscrits de la Bibliothèque Impériale, t. XXI. Paris, 1865. Collectio judiciorum de novis erroribus, t. 1. Paris, 1728.
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E. Miscellaneous Works Cited in Text Aristotle Bacon, Roger De Wulf, M.
S. Thomae Aquinatis
Works (Oxford Translation, edited by W . D. Ross, in 11 volumes, published 1921-1931). Opus Majus. Bridges' edition. Vol. 3. London, 1900. History of Mediaeval Philosophy. Messenger's translation from the 5th French edition: Vol. 1. London: Longmans, 1926. Opuscula Omia and Quaestiones Disputatae. 9 vols. Paris: Lethellieux.
NOTE: Citations of the above works in the text are in many cases made under the name of the author alone: e.g., "Valois," "Schindele," etc.
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John Buridan on the Habitability of the Earth I. Introduction Pierre Duhem has indicated the importance of the work of John Buridan of Béthune in laying the foundations of the modern science of mechanics. Buridan was the senior member, and the original and constructive genius, of that group of fourteenth-century moderni described by Duhem as 'the Parisian precursors of Galileo.' His ideas in dynamics were given mathematical formulation by Nicholas of Orêsme, and were carried to the new universities of central Europe by such distinguished pupils as Marsilius of Inghen and Albert of Saxony. In the sixteenth century, this 'tradition of Buridan' found expositors and defenders in northern Italy, where it exercised a decisive influence on the thought of Leonardo da Vinci and of Galileo.1 Little is known of Buridan's life. He was born at Béthune, near Arras, around 1300 A.D., and was rector of the University of Paris in the year 1328.2 About this time he visited Avignon on some mission to the papal court, pausing en route to take meteorological observations in the Cévennes mountains.3 His name appears in the university archives, and in the Vatican Register, in connection with benefices and honours conferred on him between 1328 and 1358, in the course of a long and distinguished career as teacher on the Faculty of Arts. These documents refer to Buridan as 'the celebrated philosopher,' or P. Duhem, Etudes sur Leonard de Vinci, IIIe Série: Les précurseurs parisiens de Galilée (Paris: A. Hermann et Fils, 1913 ). 2 Denifle & Chatelain, Chartularium universitatis Parisiensis, II (Paris, 1891), No. 870. Apparently this document was overlooked by Dr. Lynn Thorndike in his History of Magic and Experimental Science, III (New York, 1934), 374, n. 14, where he states that Duhem and Hauréau were mistaken in saying that Buridan had been rector prior to the year 1340. 3 P. Duhem, Le Système du Monde IV (Paris: A. Hermann et Fils, 1916), 126. 1
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as 'our most distinguished man,' and indicate that he was held in high esteem by his colleagues and superiors.4 Buridan appears to have had only one scholastic enemy: Nicholas of Autrecourt, the 'mediaeval Hume.' Nicholas' sceptical ideas arfe attacked repeatedly in Buridan's writings, and it was Buridan who signed the prohibitory statute of 1340, in which the Faculty of Arts condemned the practice of applying strict logical analysis to scriptural texts, as pursued by Nicholas of Autrecourt and his disciples.5 The last documentary mention of Buridan is dated July 12, 1358, and consists of a concordat between the Picard and English nations, signed by Buridan as representative of the Picards.6 It is probable that Buridan's career was terminated in that year by death from the plague, for his name ceased thenceforth to occur in the university records. The extant writings attributed to Buridan consist almost exclusively of Expositions and Questions on the treatises of Aristotle. In this field he was extremely prolific, his lectures covering the entire corpus of authentic aristotelian writings, with the exception of the works on animals and the Poetics. These lectures follow the order and subject matter of the aristotelian treatises, but those which are in the form of Questions are very independent of the text, and are equivalent in most cases to original treatises.7 It was in the field of physics, and particularly in dynamics, that Buridan's thought was most original, constructive, and influential. This fact was emphasized by Duhem, who rated Buridan a mediocre astronomer, and credited Orêsme and Albert of Saxony with the theories and discoveries which mark the beginnings of modern kinematics and statics. A more careful examination of fourteenth-century scientific writings shows, however, that most of the ideas advanced by 4 Chartul. Univ. Paris, II, 307, n. 1; and nos. 1146, 1156, 1165. See also Denifle & Chatelain, Auctarium chartularii universitatis Parisienis, Liber procuratorum nationis Anglic anae, I (Paris, 1894), col. 41. 5 Buridan deals with Nicholas' doctrines in his Quaestiones in octo libros Physicorum Aristotelis, I (edited by John Dullaert, Paris, 1509), Lib. I, Qu. 4, fols 4 T -6\ and also in his Quaestiones in Metaphysicam Aristotelis (edited by J. Badius, Paris, 1518), Lib. II, Qu. 1, fol. IX'. 6 Auctarium chartul. univ. Paris., I, cols. 206, 212, and 233-235. 7 B . Geyer, Ueberwegs Qrundriss der Geschichte der Philosophie, Band II (11th edition, Berlin, 1928), p. 595, gives the list of printed editions. The manuscript texts are discussed by K. Michalski, 'Les courants critiques et sceptiques dans la philosophie du XIV e siècle,' in Bulletin International de VAcademie Polonaise des Sciences et des Lettres, Classe d'Histoire et de Philosophie. Année 1925 (Cracow: Imprimerie de l'Université, 1927), pp. 202-209.
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The Habitabilité of the Earth Orêsme and Albert in these fields were derived from Buridan, who in turn seems to have borrowed them from earlier fourteenth-century teachers at Oxford and Paris. The whole question of Buridan's originality, and of the significance and coherence of his work in physical science, requires for its determination a much greater knowledge of fourteenth century scientific writings, and a more exhaustive study of Buridan's own works, than has yet been achieved.8 Quite apart from the question of originality or genius, however, Buridan's writings have great historical value and interest. For one thing, they cover practically the whole field of scientific and philosophical knowledge and opinion, of the fourteenth century, and thus form a kind of Summa philosophiae for that period. Their method of discussion, furthermore, gives them particular value as sources of information concerning the state of fourteenth-century scientific knowledge as a whole. In his capacity as teacher, Buridan takes it upon himself to set forth all the diverse views and arguments of his contemporaries on each problem, and in many instances he confines himself to such exposition, leaving it to the auditor or reader to make his choice among the alternative positions. Such is the case in his treatment of the problem of the rotation of the earth on its own axis, given in Question 22 of the second book of his Quaestiones super libris de caelo et mundo. In this Question, Buridan expounds the theory of diurnal rotation which Copernicus was to defend more than one hundred and fifty years later, giving excellent arguments in its favor. He then argues against the theory from the standpoint of the Ptolemaic astronomy, and indicates his own preference for the latter system. But he clearly points out to his students that the newer theory is entirely defensible, since the observed movements of the heavenly bodies may be described in function of one hypothesis as well as of the other.9 8 P. Duhem, Le Système du Monde, IV, 135-142, discusses Buridan's astronomy. O n the ideas in statics advanced by Albert of Saxony, see P. Duhem, Les Origines de la Statique, II (Paris: A . Hermann et Fils, 1906), ch. X V . On Orêsme, see P. Duhem, Etudes sür Leonard de Vinci, III' Série (Paris, 1913), pp. 346-398, and E . Borchert, "Die Lehre von der Bewegung bei Nicolaus Oresme," in Beiträge zur Geschichte der Philosophie des Mittelalters, Band XXXI, H f t . 3 (Muenster, 1934). 9 J . Buridan, Quaestiones de caelo et mundo, II Q u . 22 (Cod. lat. monac. 19551, fol. 9 9 r ) : " E t indubitanter verum est quod si esset ita sicut ista opinio ponit, omnia in caelo apparerent nobis sicut nunc apparent." This Question was edited
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The text here edited, dealing with the problem of the habitability of the earth, is based on two manuscripts of Buridan's Quaestiones super libris de caelo et mundo, where it appears as the seventh Question of the second book. The two manuscripts utilized for this edition are from the Bavarian State Library at Munich (Cod. lat. monac. 19551), and from the library of Bruges ( Ms. 477, anon.). The correspondence of the Questions on the De caelo, contained in the anonymous Bruges manuscript, with those attributed by the Munich manuscript to John Buridan, was discovered by the Abbé Michalski. Since the only copies of this work previously known were those offered by two manuscripts at Munich, and since the Bruges text is more complete and more legible than that of the Cod. lat. monac. 19551, Michalski's identification is of great value.10 The Munich Codex 19551 contains 149 folios, closely written in Gothic cursive of the late fourteenth century. The colophon to Buridan's Questions on the De generatione et corruptione, on fol. 125T, gives 1378 as the date of the copy; and since the handwriting of this text appears to be the same as that of the copy of Buridan's Questions on the De caelo et mundo immediately preceding, we may conclude that both works were transcribed in this manuscript around the year 1378. The Questions on the De caelo et mundo cover folios 70r-105T, and consist of twenty-five Questions on Book I of Aristotle's treatise, twenty-three on Book II, two on Book III, and eight on Book IV. The colophon, at the foot of the second column on folio 105T, attributes the text directly to Buridan, as follows: "Expliciunt quaestiones super libris de caelo et mundo Magistri Johannis Buridani Rectoris Parisius.' by J. Bulliot, "Jean Buridan et le mouvement de la terre, Question 22" du second livre du 'De Coelo,' " in Revue de Philosophie, 14e année, t. X X V (Paris, 1914). Bulliot's text is that of the Munich Ms 19551. 1 0 K. Michalski, "La physique nouvelle et les différents courants philosophiques au XIV e siècle," Bulletin International de FAcadémie Polonaise des Sciences et des Lettres, Classe d'Histoire et de Philosophie, Avril-Juin 1927 (Cracovie: Imprimerie de l'Université, 1928), pp. 114-117. Not having had the opportunity to examine the Cod. lat. monac. 19551, or Bruges 411, directly, 1 have followed the careful report on them given by Michalski in the above monograph; my edition of the text is based on photostatic copies of the folios containing Buridan's Qu. de caelo et mundo. I have to thank the director of the Bayerische Staatsbibliothek for his courtesy in arranging for the taking of photostats of the cod. lat. monac. 19551, fols. 70 r -125 T , in my behalf. The other Munich manuscript, purporting to contain a copy of this work of Buridan, is Cod. lat. monac. 761-, due to war conditions, I have been unable to obtain either a photographic reproduction of this manuscript, or a description of its contents.
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Other works of Buridan are also contained in this Munich codex: an abbreviated version of his Questions on Aristotle's Physics, a set of his Questions on the De generatione et corruptione, and an incomplete set of his Questions on Aristotle's Parva naturalia. While Duhem, on the basis of an inaccurate report of the manuscript transmitted to him by Père Bulliot, asserted that these texts were reportata rather than literal copies of Buridan's lectures, Michalski concludes, after careful examination and comparison of extant manuscripts copies, that the Munich text of the Questiones de caelo et mundo is to be attributed to Buridan.11 The Questiones de caelo et mundo contained in the anonymous Bruges Ms 411 commence on fol. 164T and end on fol. 210r, followed by a table of the Questions, covering fols. 210r-210T. The Questions contained in this text are identical with those of the Munich codex, except that it contains an initial Question ( Utrum de mundo debet esse scientia distincta a scientia libri Physicorum) which is missing from the Munich manuscript. The Bruges copy is in all respects superior to that of Munich; it is more carefully transcribed, more free from lacunae, and more legible. Though on palaeographic grounds it is not to be considered earlier than the Munich codex, but probably slightly later, its relatively greater completeness indicates that it is either a more faithful copy of a common original, or a copy of a more accurate earlier text. The two manuscript copies are unquestionably of common ancestry, the variants being quite obviously due to the copyists. In almost all instances it is the scribe of the Munich codex who is at fault, by reason of haste, inattention, or lack of comprehension of the work being copied. The seventh Question on the second book of Aristotle's De caelo, in which Buridan discusses the problem of whether the whole earth is habitable, is here edited for the first time from the two manuscripts above mentioned. In Cod. lat. monac. 19551, this Question extends from fol. 87r, col. A to fol. 88r col. B; in the Ms. Bruges 411 it runs from fol. 188v col. A to fol. 189T col. B. The problem of the habitability of the earth, treated in this Question, was not new in the mediaeval tradition. The geographical information and misinformation contained in Pliny's Naturalis Historia was known to mediaeval writers, and utilized to some extent in their discussions. But their interest in the problem, and their methods of 11
Michalski, "La physique nouvelle, etc.," loc. cit., pp. 115-116.
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seeking its solution, were inspired by Aristotle rather than by Pliny; they were concerned with the causes which determine and limit the possibilities of human habitation of the earth, rather than with the mere facts as to how much of the earth is actually inhabited. Hence little attention is paid to the descriptive information provided by explorers and travellers, except insofar as it may confirm the theoretical grounds. The discussion is pursued in terms of astronomy and geology, sciences which underlie geography by exhibiting certain general causes which limit geographical possibilities. It is because the principles of the solution of the problem are astronomical and geological, that Buridan raises the question of the earth's habitability in his lectures on the De caelo et mundo12. Buridan's discussion falls into two main divisions: he first treats of climatic conditions determined by astronomical causes, as factors limiting the habitability of the earth, and he then deals with the problem of why the dry land has not long since been washed into the sea. The discussion of climates involves the traditional distinction of the five zones, and is chiefly devoted to the problem of whether or not the equatorial zone, and the south temperate zone, are fitted for human habitation. Most of the arguments invoked are purely astronomical, but the Arab philosopher Ibn-Sina (Avicenna) is cited as authority for the theory that the most temperate of all climates is found at the equator, and for a story that some men had penetrated to this region and had brought back reports of a great civilization there, possessed of all the perfections of an earthly paradise. Buridan's attitude toward this tale of Avicenna, and toward the Arab philosopher's a priori arguments in support of it, is reserved if not indeed sceptical.13 1 2 T h e aristotelian text of the De caelo does not directly raise this question at all, though the discussion in Book II, ch. 4 fols. 287a 32-287" 21, of the sphericity of the earth and of the regions of the four elements, is relevant to the problem, as Buridan's discussion shows. T h e traditional locus of this problem of the habitability of the earth was Aristotle's Meteorologica, II, ch. 5, 362® 33-262b 29, where climates and winds are discussed. Thus Aquinas' treatment of the problem is found in his Expositio in Meteorologicam Aristotelis, II, Lect. X (Leonine ed., Ill, 419-420), and not in his commentary on the De caelo. 1 3 This theory of Avicenna is twice mentioned by Roger Bacon, in the Opus maius (ed. J. H . Bridges, Oxford, 1897-1900), Part IV, Dist. IV, ch. 4, and in the Opus tertvum (ed. J. S. Brewer, London, 1859), pp. 119-120. Bacon cites as sources the first book of Avicenna's Canon, and the first book of his treatise on animals. I have been unable to locate this second citation in the Venice, 1J30, edition of Avicenna; the first refers to the Canon, Lib. I, Fen II, Doctrina II, cap. 8 (Avicennae medicorum arabum principis Liber Canonis . . . Basileae, per loannes Hervagios, 1556, pp. 62-63).
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The Habitability of the Earth More interesting, from the scientific point of view, is the discussion given in the second part of the Question. Since water is lighter than earth, and since the elements tend toward equilibrium at their proper levels, it would seem that the whole earth should be covered by water. This theory is confirmed by the observed phenomenon of erosion, indicating that over a long period of time the dry land should have been completely washed into the sea by the action of rivers and rain. Since this has obviously not happened, there must be some constant process which counterbalances erosion, by which the elevation of the continental areas above sea level is maintained. Two theories are suggested. The first rests on the postulate that the sphere of water is eccentric to the earth, so that its natural center is outside the center of the earth. Several objections are raised against this view, which seems to Buridan insufficient because of its failure to give any natural cause of such eccentricity. He therefore offers another 'more probable' theory, based on the distinction between center of gravity and center of magnitude. If we assume a common center of gravity for both earth and water, the water will always flow to its natural level with respect to this center, and since it is a fluid its center of magnitude will always be practically coincident with its center of gravity. But the center of magnitude of the earth need not coincide with its center of gravity, because earth is not a homogeneous fluid like water. On the contrary, the continental areas, which are exposed to the heat of the sun and to pulverization and admixture of air, will be lighter and less dense than those parts of the earth which are under the sea. Since, therefore, the earth is not strictly symmetrical but has more dry land on one side than on the other, it cannot become symmetrical in this respect, because its center of gravity cannot become coincident with its center of volume. The processes of erosion tend to make the dry side of the earth smaller in relative volume; but in so doing they make it lighter, and thus offset the change effected in the earth's center of volume, by an equal change in its center of gravity. This theory, which seems to please Buridan greatly, affords an explanation of a number of phenomena. Besides accounting for the continued existence of dry land despite long continued erosive processes, it affords an explanation for the formation of mountains, replacing the numerous fantastic theories advanced by ancient writers. It likewise 14
P. Duhem, Etudes sur Leonard de Vinci, III' Serie, pp. 32-33.
Ill
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explains the presence of fossils in regions far from the sea, and offers a basis for a mechanical explanation of earthquakes. Possibly Buridan was aware of these applications of his theory, for fossils and earthquakes were observed and discussed in mediaeval times. Leonardo da Vinci, in any case, made the application to the problem of fossils, having become acquainted with Buridan's theory of the movement of the earth by way of Albert of Saxony.14 The significance of Buridan's discussion and resolution of this problem of land and sea lies in the fact that he sought, and found, a strictly mechanical explanation of a geological problem. This explanation was, in essentials, the theory of isostasy which plays such a basic part in modern physical geology. Whether the theory was original with Buridan, or taken by him from some unidentified predecessor or contemporary, is a matter of conjecture. Dr. Lynn Thorndike has found a full statement of the theory in an anonymous treatise on natural philosophy written in the fourteenth century; but the content of this treatise, as described by Dr. Thorndike, indicates that it was written in the latter part of the century, and probably after Buridan's death.15 It is interesting to compare Buridan's discussion concerning the habitability of the earth with that which St. Thomas Aquinas offers on the same topic in his commentary on the Meteorologica of Aristotle.16 St. Thomas is content to restate Aristotle's conclusions and arguments as they stand, without seeking to develop the problem further. Buridan, by contrast, takes the aristotelian text as a point of departure for independent inquiry—an inquiry primarily determined by mechanical principles in relation to observable phenomena. Arguments of a teleological and analogical order, though taken into consideration, no longer figure as 'demonstrations,' but only as 'persuasions.' Physical explanation is conceived in terms of forces, resistances, and measurable or observable factors. 1 5 L. Thorndike, History of Magic and Experimental Science, III, pp. 580-581. Many of the theories advanced in this treatise, as described by Dr. Thorndike, are characteristic of Buridan himself. It cannot be a work of Buridan, however, since its author opposes Buridan, and defends Ockham's position, on the fundamental problem of whether or not motion is an absolute entity distinct from the mobile quod movetur. Buridan's theory of the center of gravity of the earth, in connection with the maintenance of dry land above sea level, was also stated by John de Fundis in 1435, according to Dr. Thorndike, op. cit., IV, 239. 1 6 Thomas Aquinas, Expositio in Meteorologicam Aristotelis, II, Lect. X (Leonine ed., Ill, 419-420).
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Is this fourteenth-century shift from a 'metaphysical, to a 'scientific* attitude toward cosmological problems a sign of the failure of the mediaeval philosophical enterprise, or of its success? This is a question worthy of our most considered reflection. II. Text (Johannis Buridani super libro secundo de caelo et mundo Quaestio Septima) Septimo consequenter quaeritur: Utrum tota terra sit habitabilis. 1
A r g u i t u r primo quod sic, quia communiter dicitur quod una quarta pars terrae est habitabilis, et non apparet ratio quare magis debeat esse una quarta habitabilis quam aliae quartae; igitur omnes quartae debent concedi habitabiles, et per consequens tota terra. E t hoc etiam apparet 5 per concessionem Aristotelis, qui concedit ita esse habitabilem terram nobis opposi tarn sicut ist am; de illis enim dicit quod ipsi habitant sursum et ad dextram, nos autem deorsum et ad sinistram. 17 Deinde arguitur quod nulla pars terrae debeat esse habitabilis, quia terra est sphaerica et in medio mundi sicut centrum, u t habetur se10 cundo huius. 18 A q u a autem naturaliter sita est supra terram et fluit semper ad locum decliviorem, propter quod etiam naturaliter efficitur sphaerica, ut habetur secundo huius; 19 ex quo sequitur quod ipsa naturaliter debet totam terram circumdare, et sic nulla pars terrae esset habitabilis propter aquas. N e c valet dicere quod sunt monies et eleva15 tiones in terra, ad quas elevationes aqua circumdans n o n attingit, ideo illae elevationes sunt habitabiles. Contra hoc obicitur fortiter, si m u n dus fuerit perpetuus ut ponit Aristoteles, quia omni tempore partes superiores ex montibus descendunt multae ad valles, et nullae vel paucae ascendunt; et sic ab infinito tempore ¿Ili montes deberent esse 20 totaliter consumpti et reducti ad planitiem. Similiter, si terra sit elevatior ubi non est mare, et depressior ubi est mare seu declivior, tunc manifestum est quod omni tempore multae partes istius terrae altioris portantur cum fluviis in p r o f u n d u m maris, unde provenit quod mare efficitur grossum et salsum; et illae partes 25 terrae non revertuntur de p r o f u n d o maris ad istam terram, imo quod 17 18 19
Aristotle, De caelo, II, ch. 2, 285" 23-5. Aristotle, De caelo, II, ch. 14, 296b 7-298« 20. Aristode, De caelo, II, ch. 4, 287b $-8. 119
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elevatur de mari per exhalationem seu evaporationem non est nisi subtile aquosum, et non grossum terrenum. Ideo videtur quod ab infinito tempore tota profunditas maris deberet esse repleta terra, et haec elevatio terrae deberet esse consumpta; et sic aqua naturaliter 30 deberet totam terram circumdare, nec deberent esse aliquae elevationes discoopertae. E t hoc etiam confirmatur ex alio, quia sicut sphaera aeris valde excedit in magnitudine et profunditate sphaeram aquae, ita, ut sit proportio elementorum, sphaera aquae debet notabiliter excedere in 35 magnitudine et profunditate sphaeram terrae; et si sit ita, ipsa debet eie vari undique super terram plus quam ad montes altissimos; ideo nihil debet remanere habitabile. Oppositum amborum apparet ad sensum. Magna enim pars terrae habitatur, et magna etiam est quae non habitatur. 40
Ista quaestio videtur mihi valde difficilis. E t primitus notandum est de ea, quod dupliciter terra potest reddi inhabitabilis: uno modo propter excessum in primis qualitatibus, maxime in calido et in frigido; alio modo propter impedimentum aquarum. E t primo dicemus de primo istorum modorum.
45
Notandum est ergo quod terra imaginatur dividi in quinque zonas secundum exigentiam corporum caelestium. Prima zona est sub circulo aequinoctiali inter tropicum Cancri et tropicum Capricorni, et directe super illam zonam decurrunt omni tempore sol et alii planetae. E t de ista zona dicunt multi quod ipsa est inhabitabilis propter excessivum 50 calorem ab ipso sole. 20 Aliae duae zonae sunt sub polis, ita quod una est sub arctico, alia sub antarctico; et extendunt se usque ad illos parvos circulos quos circa polos mundi describunt poli zodiaci moti motu diurno. E t dicitur quod illae duae zonae sunt inhabitabiles ex nimio frigore propter elonga55 tionem a sole. 21 Aliae duae zonae sunt una inter tropicum Cancri et parvum circulum arcticum, in qua habitamus; alia similiter est ad aliam partem inter tropicum Capricorni et parvum circulum antarcticum. E t istae duae reputantur communiter habitabiles et satis temperatae, quia nec sunt 60 sub sole nec nimis distant a sole. 22 20 21 22
Cf. Aristotle, Meteorologica II, eh. 5, 362" 5-8. Cf. Aristotle, Meteorologica II, eh. 5, i62b 8-9. Ibid., 362b 5.
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Ita dicunt multi communiter quantum est ex caliditate et frigiditate; et omnes, ut mihi videtur, concesserunt quod duae zonae sub polis sunt inhabitabiles vel nimis difficilis habitations propter nimium excessum frigoris et recessum earum a sole. Omnes etiam concesserunt 65 zonam inter tropicum Cancri et parvum circulum arcticum esse habitabilem, quia experimur eius habitationem. Sed de aliis duabus zonis fuerunt diversae magnae opiniones.
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75
80
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90
95
E t modo dicemus de zona media quae est inter tropicos sub aequinoctiali. Statim enim prima facie apparet quod ilia propter nimium calorem sit inhabitabilis, quia procedentes usque ad tropicum Cancri inveniunt tantum calorem, quod ibi homines ultra communem m o d u m hominum aduruntur et fiunt nigri, sicut apparet de Indis et Aethiopibus; ideo videtur quod ultra esset tanta caliditas quod non possent ibi homines habitare. E t hoc confirmatur, quia si esset ultra habitatio, aliqui nostrum venissent ad eos, vel illi venissent ad nos; quod non est auditum, ut aliqui dicunt. T a m e n hoc non obstante Avicenna 23 opinabatur contrarium, dicens quod sub aequinoctiali erat summe bona et temperatissima habitatio; et dicebat se audivisse quod aliqui venerunt ad ilium locum qui reversi erant et narrabant de una maxima et nobilissima civitate quae erat sub circulo aequinoctiali. Et Avicenna habet plures rationes per se. Prima est, quod semper illic sunt dies aequales noctibus, et ideo frigiditas noctis temperai calorem diei et e contrario. Secunda ratio est, quod licet sol transeat directe super capita eorum, tamen statim transit et non multo tempore manet ibi. In sphaeris autem declivibus dies sunt valde longi et sol, licet non directe veniat super capita hominum, tamen venit prope et non cito transit, imo longo tempore girat circa capita hominum. Et ideo non oportet quod sub aequinoctiali sit tanta caliditas quanta est hic aliquando in aestate, nec unquam est ibi intensa frigiditas; ideo locus est ibi temperatissimus. Tertia rado est, quia supponimus caelum et astra esse perfectissime ordinata ad gubernandum istum mundum, et maxime homines et animalia et plantas, de quibus natura propter eorum nobilitatem debet esse maxime sollicita;ideo rationabile est quod ad ilium locum sit perfectissima hominum habitatio ad quem omnes stellae caeli ordinatae
23
Avicennae medicorum arabum principis Liber Canonis, de medicinis cordialibus, et Cantica . . . Basileae, per loarmes Hervagios, 1556, Lib. I, Fen II, Doctrina II, cap. 8 (pp. 62-63), Cf. Roger Bacon, Opus maius, Part IV, Dist. IV, cap. 4 (ed. J. H . Bridges, Ox. 1897-1900), and Opus tertium (ed. J. S. Brewer, London, 1859), pp. 119-120, who cites Avicenna's first book on animals as source of this opinion. 121
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sunt et simul habent aspectum; sed hoc est ad locum sub aequinoctiali. IUis enim omnes stellae oriuntur et occidunt, nobis autem nunquam oriuntur stellae quae sunt iuxta polum antarcticum; ergo illic debet esse summe bona habitatio. Unde Avicenna sub aequinoctiali dicit esse 100 paradisum terrestrem in quo semper omni tempore plantae frondent et florent et fructificant, et omni tempore biada matura colliguntur et alia seminantur.
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Sicut dubitatum est de zona media, ita aliqui dubitant de ilia zona quae est inter tropicum Capricorni et parvum circulum antarcticum. Dicunt enim aliqui quod licet ista zona quam habitamus sit temperata et habitabilis, tamen non sequitur quod ilia alia zona sit temperata vel habitabilis, propter unam imaginationem de sole. Astrologi enim ponunt solem habere eccentricum, et ita sol multo remotior est a terra quando est in auge eccentrici, et est multo propinquior terrae quando est in opposito augis. Modo agens naturale, quanto est propinquius passo, tanto fortius agit in ipsum; et quanto est remotius a passo, tanto debilius agit in ipsum. Modo ultra dicunt isti quod in Cancro sol est in auge eccentrici, et in Capricorno est in opposito augis; et ideo sequitur quod ista zona nostra efficitur temperatior quia in aestate, sole existente, in Cancro et quasi supra nos, sol est valde remotus a terra, propter quod calor est minus intensus. Sed in hieme, sole existente in Capricorno, fit nobis frigiditas quia sol est nobis valde obliquus; tamen quia sol tunc est propinquus terrae non fit nobis tanta frigiditas sicut si esset remotus. E contrario autem est de illa alia zona quae est ultra tropicum Capricorni; quia cum sol est in Capricorno ipse est quasi supra capita eorum, et cum hoc est propinquus terrae; ideo nimis intense calefacit, et non potest habitari vel male potest habitari illa regio propter nimium calorem. Sed quando sol est in Cancro, tunc est illis valde obliquus, et cum hoc est multum a terra remotus; ideo valde modicam virtutem habet super illos, ideo efficitur ibi frigiditas nimis intensa et prohibens bonam habitationem.
Nunc restat dicere de inhabitatione propter aquas. Et sunt de hoc tres magnae opiniones. Aliqui ponunt unam solam quartam vel quasi habitabilem, et alii ponunt omnes quartas terrae habere habitationes. 130 Et de ista opinione erit primo dicendum. Isti ergo dicunt tam terram quam aquam esse concentricas mundo, ita quod centrum mundi sit centrum earum ambarum; tamen dicunt in qualibet quarta terrae esse multas plagas discoopertas aquis, propter multas terrae gibbositates et quasi montium elevationes eminentes 135 super aquas. Et dicunt multas alias partes terrae esse coopertas aquis 122
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propter earum depressiones, ad modum vallium inter praedictas elevationes. Et hoc dicunt ita esse in qualibet quarta terrae, cuius signum est quod de una plaga valde magna discooperta nos pertransimus valde magnum et longum mare et venimus ad aliam plagam discoopertam 140 valde magnam, et verisimile est quod ita esset circumeundo terram totam. Sed contra istam opinionem sunt duae magnae dubitationes Prima est, quia omnia maria quae ab aliquibus poterunt transiri, et omnes terrae habitabiles quae poterunt inveniri, continentur in ista quarta 145 terrae quam habitamus. Et aliqui laboraverunt in mari ad permeandum mare in aliis quartis, et nunquam potuerunt pervenire ad aliquam terram habitabilem; et ideo dicitur quod Hercules in finibus huius quartae infixit columnas, in signum quod ultra eas non erat terra habitabilis nec mare permeabile. 150 Alia dubitatio difficilior est, quae dicta fuerit prius, quia haec opinio non potest salvare, si mundus fuerit aeternus, quo modo istae elevationes terrae possunt salvari ab aeterno, cum semper ex eis fluant multae partes terrae cum fluviis ad fundum maris. Iam enim ab infinito tempore deberent tales fundi marium esse repleti, et deberent eleva155 tiones terrarum esse consumptae; quod non est conveniens dicere volentibus tenere perpetuitatem mundi in statu prospero animalibus et plantis sicut nunc est. Ideo alia fuit opinio, quae ponebat quod ad salutem animalium et plantarum Deus et natura ab aeterno ordinaverunt aquam eccentricam, 160 ita quod centrum terrae sit centrum mundi, sed centrum aquae sit extra centrum mundi. Et sic dicunt aquam semper defluere ad locum decliviorem non respectu centri terrae vel mundi sed respectu proprii centri aquae. Et sic potest esse una pars terrae quasi quarta discooperta aquis, omnibus aliis existentibus coopertis aquis. Et sic isti salvant quod 165 non sit nisi una quarta terrae, vel quasi, discooperta et habitabilis. Sed contra istam opinionem remanent iterum duae dubitationes. Prima est, quia iste mundus regitur a Deo, sed tamen mediante caelo si volumus loqui naturaliter. Et ideo ex parte caeli oportet assignare causam illius eccentricitatis. Non enim posset bene assignari ex parte 170 terrae, cuius partes sunt consimiles et homogeniae; nec etiam ex parte aquae cum eius partes sint etiam consimiles et homogeniae; nec ex parte caeli moti, quia illud indifferenter et undique volvitur circa terram et circa aquam, ideo ex parte ipsius non potest poni ratio quare centrum aquae esset extra centrum terrae magis ad unam partem quam 175 ad aliam. Secunda dubitatio est, quo modo montes sic possent infinito tempore salvari, cum omni tempore multae partes de locis altioribus descendant 123
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ad loca inferiora, et paucae ascendant vel portentur de locis bassis ad loca alta, maxime si velimus loqui de valde aids montibus; ideo in infinito tempore illi montes alti deberent esse consumpti. Propter hoc est tertia opinio, quae videtur mihi probabilis, et per quam perpetuo salvarentur omnia apparentia, ponendo quod tam terra quam aqua sunt concentricae mundo, ita quod tota terra est innata congregari circa centrum mundi, et etiam omnis aqua est innata fluere ad locum decliviorem respectu centri mundi. Sed multa aqua est in visceribus terrae, et multa etiam est commixta aeri per evaporations; ideo non oportet tantam aquam esse in mari quod excedat elevationes terrae. Sed tunc quaeritur quo modo aeternaliter salvabunter illae elevationes terrae. Respondetur, si secundum Aristotelem poneretur mundus aeternus, quod ab aeterno ad salutem animalium et plantarum mundus est ordinatus quod una pars terrae, quasi una quarta, est discooperta aquis et eminens super aquas; et semper manet et manebit etiam naturaliter discooperta, non obstante concentricitate et licet etiam circumscriberemus montes. Et est talis imaginatio, quod terra in parte discooperta alteratur ab aere et a calore solis, et commiscetur sibi multus aer, et sic fit ilia terra rarior et levior et habens multos poros repletos aere vel corporibus subtilibus; pars autem terrae cooperta aquis non sic alteratur ab aere et sole, ideo remanet densior et gravior. Et ideo qui divider et terram (/. si divideretur terra) per medium suae magnitudinis, una pars esset valde gravior quam alia, ilia enim pars in qua terra esset discooperta esset multo levior. Et sic apparet quod aliud est centrum magnitudinis terrae, et aliud est centrum gravitatis eius; nam centrum gravitatis est ubi tanta est gravitas ex una parte sicut ex altera, et hoc non est in medio magnitudinis ut dictum est. Modo ultra, quia terra per suam gravitatem tendit ad medium mundi, ideo centrum gravitatis terrae est medium mundi, et non centrum suae magnitudinis, propter quod terra ex una parte est elevata supra aquam et ex alia parte est tota sub aqua. Sed tunc cum quaeris ultra, cum partes illius terrae elevatae fluant cum fluviis ad aliam partem ad fundum maris, quo modo potest salvari ista elevatio; respondetur quod si multae partes terrae elevatae moventur ad aliam partem ad fundum maris, tunc gravificant illam partem ad quam fluunt, et tunc semper in residuum quod manet discoopertum agunt sol et aer, et reddunt illam partem leviorem, et ita ilia pars quae prius erat centrum gravitatis non amplius erit centrum gravitatis. Ideo oportet quod totalis terra moveatur et elevetur versus plagam discoopertam; et tunc ex hoc sequitur ultra, per processum temporis, 124
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220 quod partes quae sunt in centro terrae tandem venient ad superficiem terrae habitabilis, propter hoc quod continue removentur de ista terra partes quae fluunt ad partem oppositam; et sic semper salvatur elevatio terrae. Sic etiam salvatur generatio altissimorum montium, quia intra ter225 ram sunt partes terrae bene dissimiles, prout experiuntur fodientes; aliquae sunt lapidosae et durae, aliae sunt magis tenerae et citius divisibiles. Cum ergo illae partes interiores terrae elevantur modo praedicto ad superficiem terrae, illae quae sunt tenerae et divisibiles per ventos et pluvias et fluvios, iterum moventur ad profundum maris; 230 aliae autem magis durae et lapidosae non possunt sic dividi et fluere, ideo manent et continue per longissima tempora elevantur per totalem terrae elevationem; et ita possunt fieri montes altissimi. Et si nulli essent modo montes, adhuc per istum modum fierent in futuro; nec apparent alii modi per quos possent generari et manere tales montes. 235 Aliqui enim ponunt quod ex motibus terrae, per exhaladones, generantur montes. Sed si hoc esset verum de aliquibus parvis montibus tarnen de altissimis montibus et longissimis non possit hoc esse verum; quia ubi esset tanta exhalatio inclusa, quae tantam terram posset elevare, non apparet bene; et si esset tanta terra elevata, tamen exeunte 240 exhalatione caderet iterum in foveam suam. Et sic patet quaestio. Varia lectio: [B = Ms. Bruges 411: Ai = Cod. lat. Monac. 19551) Seprimo om. B. 2. pars om. B. 3. aliae quartae] alia Ai. 13. esset] est Ai. 20. totaliter] tori B. 25. quod om. M. 26. seu] vel Ai. 32. etiam om. M. 34. debet] deberet Ai. 39. habitatur] inhabitatur M. 40. valde om. Ai. primitus . . . ea] primo notandum Ai. 45. est ergo] igitur M. 53. describunt om. M. 53. moti] in Ai. 56. Cancri om. B. 61. multi om. M. 64. edam] autem Ai. 69. 75. aliqui . . . venissent] aliquis enim om. M. 70. sit] est Ai. vestrum venisset B. 79. dicebat] dixit Ai. 79. venerunt] fuerunt B. 79-80. q u i . . . erant om. B. et nobilissima om. M. 84. est om. M. 85. tamen] cum B. 87-88. longo tempore] longe B. 95—96. ordinatae . . . habent] habent ordinate et simul B. 100. semper om. M. 105. quod om. B. 109. terrae om. M. 113. ideo] tunc B. 115. e t . . . nos] est quasi nos supra B. valde om. B. 122. habitari] inhabitari Ai. 129. omnes . . . habitationes] habere alias quartas M. 132. ambarum om. B., add. in marg. Ai. 135. coopertas] discoopertas Ai. 140. esset] accideret Ai. 146-147. terram] partem Ai. 125
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148. infixit] fixit M. 148. erat] esset M. 150. fuerit] fuit M. salvare] salvari B. 152. ab aeterno] ex terra M. 158. salutem] saltum M. 162. non] in M. sed] sed non Ai. 163. quarta] esse add. B. 165. terrae om. M. 165. et] edam M. 166. opinionem om. M. quia] quod M. 171. cum . . . homogeniae] propter eandem rationem M. 172. illud] non M. 176. est om M. 178179. vel . . . alta] e contrario M. 179. in om. M. 182. quod] quoddam M. 184. fluere] defluere M. 198. repletos . . . subtilibus] corporibus subtilibus vel ipso aere M. 200. terram om. M. 202. qua terra] aqua M. discooperta] ilia autem add. M. 204. eius om. M. 205. altera] alia M. 208. est medium] fit in centro B. 209. supra] extra M. 2IS. discoopertum] indiscoopertum B. 217. erat] fuit M. 217. erit] manet M. 227. ergo] igitur M. 230. magis] nimis M. 230 et fluere] nec fluere M. 232-233. Et . . . montes] Et simili modo essent montes Ai. 234. tales] tanti Af. 237. possit... esse] esset M. 239. terra om. M. exhalatione] sua add. M. 241. E t . . . quaestio om. B.
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Ockham, Buridan, and Nicholas of Autrecourt T H E PARISIAN STATUTES OF 1339 AND 1340 I. Ockharmsm at Paris: the Problem In the Chartularium Universitatis Parisiensis, under the dates September 25th, 1339, and December 29th, 1340, we find two statutes of the Faculty of Arts which are described as defense measures against the incursion of Ockhamist teachings into the Parisian university. The first of these statutes, while not condemning any doctrines, prohibits the "dogmatizing" of the teachings of William of Ockham, on the ground that his writings had not been authorized as admitted texts, and had not been examined for possible errors. The statute of 1340, on the other hand, explicitly condemns certain statements and practices, but does not attribute them to Ockham's doctrine or method. Nevertheless this decree does mention Ockham's name in a final paragraph, stating that the provisions of the previous year's statute are to remain in force.1 Does this statement mean that the statute of 1340, like that of the previous year, was aimed at doctrines stemming from William of Ockham? The historians of mediaeval philosophy have so interpreted it, and have been led thereby to the conclusion that the whole series of doctrinal condemnations of the following decade, specifically envisaging the teachings of Nicholas of Autrecourt and of John of Mirecourt, were anti-Ockhamist measures. On the assumption that the 1340 statute was aimed at Ockhamism, this conclusion is prima facie plausible, because it can be shown that at least one of the statements Chartularium universitatis Parisiensis, ed. by Denifle-Chatelain, Vol. II (Paris 1891), no. 1042, pp. 505-7: "Si quis autem contra premissa vel aliquod premissarum attemptare presumpserit, a nostro consortio ex nunc prout ex tunc resecamus et privamus, resecatum et privatum haberi volumus, salvis in omnibus que de doctrina Guillelmi died Ockam alias statuimus, que in omnibus et per omnia volumus roboris habere firmitatem." 1
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Ockham, Buridan, and Nicholas of Autrecourt reproved by the 1340 statute had been made by Nicholas of Autrecourt, who in turn was the object of an official condemnation issued in 1346, his books being burned in Paris in 1347.2 The characterization of Nicholas of Autrecourt as an Ockhamist thus seems to find historical justification in the connection between the measures taken against Nicholas in 1340, 1346, and 1347, on the one hand, and the statute of 1339 on the other, which forebade the "dogmatizing" of Ockham's doctrines. This connection itself, however, rests entirely on the assumption that the last sentence of the 1340 statute, which calls attention to the fact that the previous year's statute is still in force, justifies the conclusion that the 1340 statute was itself directed against Ockhamist teachings. Since this assumption is by no means necessitated by the wording of the 1340 statute, and leads moreover to strange paradoxes when we attempt to account for other definite historical facts, it seems worth while to examine the relevant evidence in the case, and to consider the possibility of a totally different significance which can be ascribed to the final sentence of the 1340 statute. Such an examination is of considerable importance for our understanding of the history and influence of Ockham's philosophical ideas and methods. If the scepticism of Nicholas of Autrecourt was the consequence and fruit of the doctrines of Ockham as a matter of historical fact and not merely as a theory of philosophical interpretation, the characterization of Ockham's doctrine as a destructive and corrosive force in late mediaevil philosophy can lay claim to a foundation in the facts of history.3 It then becomes necessary to find an ex2 Cf. J. Lappe, "Nicolaus von Autrecourt," in Beiträge zur Geschichte der Philosophie des Mittelalters, ed. Clemens Baeumker, vol. VI, fasc. 2, Münster, 1908, pp. 1-3. Also B. Geyer, in Ueberwegs Grundriss der Geschichte der Philosophie, II (Berlin, 1928), 589-590, who links together the statutes of 1339-40 with the condemnations of Nicholas of Autrecourt and John of Mirecourt, as follows: "Paris und seine Universität bildeten einen Hauptherd für die ockhamistischen Neuerungen. Dies lassen schon die oben erwähnten Verurteilungen der Jahre 1339 und 1340 erkennen . . . Ein noch grelleres Licht auf den mächtigen Einfluss Ockhams, seiner Lehren und insbesondere seiner kritischen Tendenzen in Paris werfen die 1346 und 1347 verurteilten Sätze, die Nicolaus von Autrecourt und Johannes von Mirecourt zu Urhebern haben." A similar view is given by M. De Wulf, History of Mediaeval Philosophy, transl. from 5th French ed., N. Y., 1926, 2, 190-191. 3 For such a criticism, cf. Anton C. Pegis, "Concerning William of Ockham, in Traditio II (1944), 465-480. Also Etienne Gilson, "The Unity of Philosophical Experience" (N. Y., 1937), ch. 3, pp. 61-91.
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planation for the fact that a group of influential and constructive thinkers, John Buridan, Nicholas Oresme, Albert of Saxony, John Gerson, and Peter d'Ailly, have always been regarded as "nominalists" and of the Ockhamist school. This paradox is revealed in a concrete historical problem connected with the statute of 1340. John Buridan, who was rector of the University in that year, signed this statute which we know to have been directed, at least in part, against Nicholas of Autrecourt. Who, then, was the Ockhamist? Was it Nicholas, the destroyer and sceptic, against whom the statute was directed? Or was it Buridan, the defender of natural knowledge and initiator of a fruitful and stable period of scientific progress at Paris? Michalski, taking note of Buridan's sincere and vigorous opposition to Nicholas of Autrecourt as evidenced in Buridan's own writings, concluded that he could not have been so much of an Ockhamist as had been supposed, and that in the 1340 statute he was expressing his opposition to the philosophical principles of Ockham. A similar view is taken by Gilson, who likewise seeks to preserve the Ockhamism of Nicholas of Autrecourt, by curtailing that of Buridan.4 But what evidence is there, in the historical facts accessible to us, for the assumption that Nicholas of Autrecourt was an Ockhamist? The extant writings of Nicholas, as Gilson himself concedes, give no indication of any direct doctrinal connection between Nicholas of Autrecourt and Ockham. 5 The writings of John Buridan, by contrast, exhibit direct influence of Ockham's teachings on almost every page, and, despite the modifications and differences to be noted between the 4
C. Michalski, "Les courants philosophiques à Oxford et à Paris pendant le XIV e siècle," in Bulletin international de l'académie polonaise des sciences et des lettres, Classe d'histoire et de philosophie, Année 1919-20 (Cracovie, 1922), pp. 76-77: "Buridan était entièrement d'accord avec les théologiens de Paris, quand il rejetait la manière d'interpréter les Saintes Ecritures et le dogme, établie, depuis Ockham, sur la distinction entre la suppositio propria et impropria, personalis et materialis. La doctrine du philosophe de Béthune ne pouvait donc l'empêcher d'occuper sa haute situation à l'université de Paris." Cf. also E. Gilson, La Philosophie au Moyen-Age (2d ed., Paris, 1945), p. 675, who goes so far as to state without qualification that the statute of 1340 was "un decret interdisant d'enseigner plusieurs des thèses d'Ockham." 5 E . Gilson, La philosophie au Moyen-Age (2d ed., Paris, 1945), p. 673: "Nicolas d'Autrecourt a soutenu des thèses qu'on chercherait en vain dans les écrits du venerabilis inceptor, et dont rien ne permet de croire qu'il les eût reconnues pour dérivant des siennes. Il n'est même pas certain qu'elles en dérivent, car rien ne prouve que l'œuvre de Nicolas d'Autrecourt ne serait pas née, à bien peu de chose près telle qu'elle est, si celle d'Ockham n'avait pas existé."
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teachings of the two men, these writings substantially justify the long established tradition which links the names of Buridan and the other "nominalists of Paris" with that of Ockham.6 Hence the association of Nicholas of Autrecourt with Ockhamism seems to rest primarily on the hypothesis that the Parisian statute of 1340, which was directed against Nicholas, was an anti-Ockhamist measure. If this hypothesis turns out to be unjustified in the light of the relevant facts and documents, there will remain little tangible foundation for the customary characterization of Nicholas of Autrecourt as an Ockhamist. And in that event the problem of accounting for the position of John Buridan as opponent of Nicholas, and for the undisturbed ascendancy and prestige of the nominalist group fathered by Buridan during the subsequent decades, will be fully resolved. The relevent documents, from which we can build up a picture of the historical situation at Paris in the years 1339 and 1340, include the two statutes of those years, the writings of Nicholas of Autrecourt, the writings of John Buridan, and, finally, the writings of William of Ockham which are thought to have occasioned the controversies which gave rise to the statutes. The clue to the whole problem, hitherto overlooked, is clearly suggested in the writings of Nicholas of Autrecourt; for these writings reveal the existence of a sustained and lively debate concerning one of the most controversial and distinctive doctrines of William of Ockham, carried on between Nicholas of Autrecourt and the Franciscan Bernard of Arezzo. An examination of the statutes of 1339 andl340, in the light of the situation revealed in Nicholas' letters to Bernard, and in connection with relevant writings of Ockham and of Buridan, can provide us with a much clearer picture of the events giving rise to these statutes, and of the significance to be attached to the final paragraph of the statute of 1340. II. The Statute of 1339: Nicholas of Autrecourt and Bernard of Arezzo. The statute of 1339 is a disciplinary measure, and not a condemnation of any specific doctrines or theses. It is in two main paragraphs, the 6 Cf. F. Ehrle, Der Sentenzenkommentar Peters von Candia, Munster-in Westf., 1925, p. 124, note 2, quoting Aventinus, Annales ducum Bolariie, II, lib. 7, c. 21, ed. S. Rietzler (Munich, 1884), p. 474: "Marsilius Bathavus, Joannes Buridanus, discipuli Vilemii Ocumensis . . ."
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first of which prohibits the "dogmatizing" of the doctrines of William of Ockham on the ground that his writings had not been officially approved as texts in usu scholarum, while the second paragraph c o m plains of the tumults raised b y auditors at the disputations, and forbids them to argue without special permission from the Master holding the disputation. T h e main provisions of the statute are as follows: Since therefore, by our predecessors, who were not unreasonably concerned as to the books to be read publicly or privately among us, there was issued a certain ordinance which we have sworn to observe; and because we ought not to read certain books not admitted by them or in common use elsewhere; and since in these times not a few persons have presumed to dogmatize the doctrine of William called Ockham, in public and also by holding secret assemblies on this subject in private places—despite the fact that this doctrine had not been admitted by those in authority, nor acknowledged elsewhere as customary, nor examined by us or by others to whom this might pertain, for which reason it does not appear to be free from suspicion—; for this reason we, mindful of our well-being, and considering the oath which we made to observe the above mentioned ordinance, decree that no person shall presume to dogmatize the said doctrine, by listening to it or lecturing on it publicly or in private, or by holding assemblies for disputation concerning the said doctrine, or by citing it in lectures or disputations. . . . Furthermore, since it is clearly evident to us that in the disputations which take place in the rue de Fouarre, such abuse has developed, that Bachelors and others present at the said disputes dare to argue on their own authority, showing very little reverence toward the Masters who are disputing, and making such a tumult that the truth of the conclusion being debated cannot be arrived at, so that the said disputations are not in any way fruitful for the listening Scholars: we therefore decree that no Master, Bachelor or Scholar, should argue without the permission and license of 7 Master holding the disputations 7 Chartularium univ. Paris., II, No. 1023, pp. 485-6: "Cum igitur a predecessoribus nostris non irrationabiliter mods circa libros apud nos legendos publice vel occulte certa precesserit ordinario per nos jura ta observari, et quod aliquos libros per ipsos non admissos vel alias consuetos legere non debemus, et istis temporibus nonnulli doctrinam Guillermi dicti Okam (quamvis per ipsos ordinantes admissa non fuerit vel alias consueta, ñeque per nos seu alios ad quos pertineat examinata, propter quod non videtur suspicione carere), dogmatizare presumpserint publice et occulte super hoc in locis privatis conventícula faciendo: hinc est quod nos nostrae salutís memores, considerantes juramentum quod fecimus de dicta ordinatione observanda, statuimus quod nullus de cetero
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Ockham, Buridan, and Nicholas of Autre court The two paragraphs of this decree of 1339, taken together, give us a rather clear picture of the state of affairs leading to the issuance of the statute. A lively controversy, revolving around doctrines of William of Ockham, had swept through the Faculty of Arts, to the extent that everyone, from the Masters down to the beginning students, was taking sides and heckling or interrupting during the regular "solemn disputations" held in the rue de Fouarre. Since it takes two armies to make a battle, it is reasonable to suppose that this controversy over Ockham's doctrines had split the university into two factions, proOckhamist and anti-Ockhamist. The statute of 1339 seems chiefly concerned to restore order and discipline, without taking sides in the controversy itself—a fact which perhaps indicates that the pro-Ockhamist faction was relatively strong, and included in its number some of the more influential and respected members of the Faculty. John Buridan may well have been one of these, since his writings, many of which represent lectures he had been giving since 1327 or earlier, show very marked influence of the doctrines and logical method of William of Ockham. From this we can at least draw one conclusion— if John Buridan had been peacefully teaching Ockhamist philosophical doctrines for twelve or fifteen years prior to 1339, we cannot ascribe the outbreak of controversy and disorder on the Faculty of Arts, in 1339, to any sudden incursion of Ockhamist teachings into the university. It is the writings of Nicholas of Autrecourt which give us a clue to the nature of the controversy of 13 39. Of these, there are extant only his letters to Bernard of Arezzo and to the Egidius who had come to Bernard's support in his debate with Nicholas, and two other writings recently edited by Father J. R. O'Donnell—the treatise Exigit ordo executionis, and a question Utrum visio creatur Gc) etc. W e would, to be sure, encounter the difficulty that the medieval logicians regarded a universal affirmative as false in the case where its subject term has no denota8
Cf. Boehner (IV), pp. 103-114, for a presentation of the "rules of supposition" drawn from Albert of Saxony. On pp. 27-51 Boehner attempts to construe these rules in terms of modern quantificational logic, but, as is convincingly argued by Matthews (I), this interpretation is highly dubious.
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turn, which would not be the case according to the modern analysis, since the conditional is true when its antecedent is false. But the discrepancy goes deeper than this. T h e medieval analysis does not, like the modern, construe both terms of a general categorical proposition as predicate-terms, and quantify over a variable whose range is the universe of individuals; rather, it quantifies over the terms themselves, dividing their reference conjunctively or disjunctively among just those individuals specified b y the term. Hence it is incorrect to represent categorical propositions as molecular in form, or as statements of the applicability of a complex propositional function to all or to some values of the unrestricted individual variable. T h e medieval analysis retains the subject-predicate interpretation of general propositions, and treats the subject-term itself as the variable of quantification. Thus medieval logicians would repudiate the interpretation of 'Every man is an animal' as equivalent to 'For anything you please, either it is not a man or it is an animal'; rather, they would say that the term 'man' in the above proposition establishes the range of reference, and that the prefix 'every' has the function of determining that the predicate is indicated to apply to the values of this range in such manner that it applies to each value. A symbolic representation of this would take some such form as ( F ) ( G F ) , or ( F x ) ( G x ) . T h e difference between the modern and medieval analysis consists in the fact that in the modern analysis it is the individual variable 'x' that is "used f o r " the things about which the statement is made, the general term being predicated of these things, whereas in the medieval analysis it is the general term that is "used f o r " (i.e., "stands f o r " ) the things about which the statement is made, and it is the other term only that is predicated of these things. Insofar as the property of supposition is ascribed to the predicate as well as to the subject of the categorical proposition, the logical structure of every general categorical proposition becomes doubly general, and both the subject and the predicate term become quantified, while the verbal copula functions as a two-place predicate. In a particular affirmative, both terms have "determinate supposition," so that the sentence 'Some man is white' is construed as 'At least one man and at least one white thing are identical.' T h e predicate of a universal affirmative, however, cannot be assigned determinate supposition, nor, of course, distributive supposition, and it is to the credit 383
The Medieval Contribution to Logic of Shyreswood and other medieval logicians that they recognized this, and saw that the predicate of a universal affirmative could not have determinate supposition, because the scope of the universal quantifier extends over it. For although we may say that every man is an animal, we cannot infer from this that some animal is every man; i.e., a doubly general proposition of the form (x) (Ey) : f (x, y) does not imply a proposition of the form (Ey) (x) : f (x, y). It was on this account that they introduced the third mode of supposition, called "merely confused," to take care of the case where an existential quantifier falls within the scope of a preceding universal quantifier.9 An interesting aspect of the theory of supposition was its use in the analysis of propositions of past tense, future tense, and of the mode of possibility. The tense of the verb or copula operates as a temporal quantifier, extending (or "ampliating") the supposition of the subject-term beyond the present time. Thus, in the sentence 'Socrates was a man,' or 'Every man will die,' the tensed verb determines that the subject term stand for its referent or referents not only for the time in which the sentence is stated but also for the time indicated by the tense of the verb. The predicate, however, is indicated to stand for those referents of the subject term only for the time specified by the tense of the verb; this function of applicability according to the tense of the verb, belonging to the predicate, was called "appellation." Since ordinary language lacks a timeless verb, or an omnitemporal verb, the potential mood ("can be") was used to extend the range of the subject's supposition, and of the predicates' application, to past, present and future time indifferently, and some logicians employed the term 'natural supposition' (suppositio naturalis) for the use of a term in this omnitemporal manner, even when used with a verb of present tense. There was, however, a lack of agreement, and perhaps some confusion, with respect to the question of whether supposition for all possible values included those which neither are, nor have been, nor ever will be actual. It appears to be impossible to give a consistent interpretation of the medieval doctrine of supposition that corresponds to any branch of modern logic. Although it suggests, in some respects, a class member9 Cf. Kneale (I), pp. 258-260, for a discussion of this point. Shyreswood, in his Introductiones, p. 39, in discussing quantifiers occurring in predicate position, clearly recognizes the problem of scope, and speaks of the first quantifier as "extending itself" to the second.
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The Medieval Contribution to Logic ship analysis of general propositions in which the quantifiers determine relations of class inclusion or of class overlap, the medieval logicians did not construe the terms of such propositions as singular names of classes, but as general names of individuals. The theory of supposition may indeed be viewed as a persistent attempt to make sense of the Aristotelian treatment of subject-terms as general names. The property of "confused supposition" for many individuals, involving the sort of ambiguous denotation which in modern languages is given to a term by use of the indefinite article, has something in common with the modern notion of a variable; and in conceiving the function of the quantifying prefixes as that of binding the term-variables and making them stand for their values disjunctively, or conjunctively, the medieval logicians did take a first step toward the modern analysis. To have taken the further step of separating the variable of quantification from the subject term, and of treating the latter as a predicate, would have transformed Aristotle's logic of terms into the lower functional calculus of modern logic; but it would have involved abandonment of the Aristotelian categorical proposition of subject predicate form. In the context of ordinary language use, and also in the context of Aristotle's theory of scientific demonstration, there was no incentive for such an abandonment. But until this further step is taken, it is impossible to exhibit the relation between the logic of truth functions and the logic of general propositions in the way it is done today. The significance of the medieval logica moderna does not consist in the discovery of a new system of logic superseding that of Aristotle, but in the attempt it made to formulate, on a metalinguistic level, the syntactical and semantical presuppositions of the Aristotelian form of logic. In seeking to carry out this enterprise, the ambiguities and hidden weaknesses of the Aristotelian system were brought to light, not only with respect to the problem of singular and general terms, and the unresolved ambiguities of Aristotle's formulations of the relation of predication, but with resjpect to the semantical questions of meaning and reference, modality, existential import, and (to borrow a phrase from W. V. Quine) ontological commitment. It was in this exploration of the semantical foundations of Aristotelian logic, rather than in the devolpment of a more general formal logic in abstraction from semantical interpretation, that medieval logicians 385
The Medieval Contribution to Logic and philosophers made their most original and interesting contributions. This part of the literature of medieval logic is only beginning to be investigated, and we can do little more than mention a few of the problems which were raised, and explored in depth, by the later scholastic writers. With respect to modal logic the medieval contributions were of three kinds. First, the important question of whether modal propositions are to be construed as object-language statements (de re) or as metalinguistic statements ( de dicto) was raised, and resolved in favor of the second (and correct) interpretation; this involved recognition that modal logic belongs to the logic of propositions and not to the logic of terms. Second, the medieval logicians devised methods of analysis of modal propositions and arguments involving quantifiers, which not only revealed the problems which depend on scope, but also brought to light a problem which is of crucial importance in contemporary theories of modal logic—namely, the problem of substitutivity of expressions occurring in modal or intensional contexts.10 The third contribution related to the semantical and epistemological interpretation of the modal concepts of necessity and possibilty, discussed in connection with Aristotle's theory of scientific principles; here a clear distinction was drawn between the absolute necessity attributed to laws of logic and the "hypothetical necessity" attributed to laws of nature, which had the historically important effect of exhibiting the "first principles" of the Aristotelian sciences of nature as empirical generalizations, or hypotheses, rather than self-evident truths. The semantical problems of meaning, reference and truth, which Aristotle treated only in a cursory manner to the extent needed for formulating his theory of the scientific syllogism, were explored in full depth by medieval logicians in connection with Aristotle's doctrine of categories, the problem of definition, and the laws of contradiction and excluded middle. Ockham's doctrine of concrete and abstract terms, and of absolute and connotative terms, constituted an atttempt to formulate a general semantics of meaning and reference consistent with his syntactical theory of supposition. Buridan, in his 10
Cf. Moody (V) for a presentation of Buridan's treatment of this problem in connection with intensional contexts determined by such words as "believes." On the de re—de dicto interpretations, and the further development of this issue, cf. Prior (I), Bochenski (II) pp. 211-2X8 and 260-266, and Kneale (I) pp. 236ff.
386
The Medieval Contribution to Logic Sophismata and in his Quaestiones in Metaphysicam Aristotelis, deals with such problems as the reference of fictitious terms, the interpretation of negative existential propositions, whether sentences have meanings distinct from the meanings of their terms (the problem of the complexe significabile), and a multitude of other questions pertinent to the philosophical aspects of logic. The paradox of the Liar, which constitutes a challenge to the universal validity of the laws of two valued logic, and also involves the question of whether the semantical rules of a language can be formulated within that language, engaged the attention of logicians throughout the fourteenth century, and generated some highly sophisticated treatments of the problem which have proved interesting to contemporary logicians in connection with Tarski's well known work on the formal definition of truth.11 It is in these areas, rather than in that of pure formal logic, that the work of medieval logicians not only anticipated, but in some respects surpassed, that of twentieth century logicians concerned with these problems.
IV The foregoing discussion suggests a few general conclusions concerning the historical and theoretical significance of medieval logic. This significance does not lie, as it seems to me, in an anticipation of the formal structure of modern mathematical logic, even though the theory of consequentiae and the treatment of quantifying prefixes as determinants of the referential relation between terms is suggestive of modern propositional logic and quantification theory. Certainly medieval logic, whose contributions were long since forgotten when Boole and Peano and Frege laid the foundations of modern logic, had no direct influence on the latter. The historical significance of medieval logic seems to lie in the part it played in disclosing the insecure semantical presuppositions of the 1 1 On the medieval treatment of the Liar paradox, cf. Bochenski (II), pp. 275292, M o o d y (III), pp. 101-110, and Boehner (III), pp. 282-285. Ockham's semantical analysis of terms is treated in detail in M o o d y (I), ch. 2, and Boehner (II). T h e medieval debate over propositional meanings is the subject of a book written in 1936 by H . Elie, entitled Le complexe significabile: Holcot's contribution to this debate is described and analyzed in M o o d y ( I V ) .
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The Medieval Contribution to Logic Aristotelian logic of terms, and the limitations of the syllogistic formulation of the logical structure of science. It did this not so much by a critique of Aristotelian logic based on different theoretical foundations, as by its persistent attempt to resolve the obscurities in the Aristotelian theory of meaning and reference and to achieve a fully general formulation of these semantical presuppositions. The doctrine of supposition was an attempt to achieve a coherent interpretation of the Aristotelian categorical proposition of subject predicate form, in which the relation of general terms to singular terms, and the relation of predicate terms to subject terms, could be exhibited. The significance of the supposition doctrine was not that it succeeded in doing this, but rather that it revealed the impossibility of formulating a general theory of reference that would satisfy all the requirements of Aristotle's formal system. There is a marked analogy between medieval logic and late medieval physics or "mechanics," with respect to their relationship to Aristotelian logic and physics on the one hand, and to the mathematical form of modern logic and of modern mechanics, on the other. The efforts of fourteenth century scholastics, such as Bradwardine, Heytesbury, Buridan, and Oresme, to "save" Aristotle's dynamics and kinematics of motion, by finding a way to account for projectile motions and gravitational acceleration within the conceptual framework of Aristotle's qualitative physics, led to such innovations as the theory of impetus, Bradwardine's exponential formulation of Aristotle's "laws of motion," and the kinematic analysis of accelerated motion developed by Heytesbury and Oresme, which had the potentiality of being generalized into foundations of a new mechanics. To have carried out such a generalization, however, would have required abandonment of the whole Aristotelian theory of natural substances and substantial forms, and the dissolution of the whole cosmological framework of Aristotelian physics and astronomy. There was no incentive to carry out such a revolution, and the fertile suggestions for such a project, implicit in the piece-meal doctrines that had been conceived as ways of patching up the Aristotelian system, remained dormant or became forgotten until, three centuries later, a mathematical approach to physics provided a conceptual framework, and a method, adequate for the exploitation of these suggestions. The historical and theoretical significance of this fourteenth century mechanics was in preparing the way for the scientific 388
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revolution of the seventeenth century b y its disclosure of the weaknesses, and of the incapability of generalization, of the Aristotelian form of physics. T h e significance of medieval logic was similar. T h e form of logic developed b y Aristotle, adequate as a formulation of the use of natural language for the type of scientific demonstrations which involve determination of the universal predicability of property-terms with respect to substance-terms, was shown to be inadequate for formulating a predicate logic of unrestricted generality. As Aristotle's substance-property physics is related to Newtonian particle-mechanics, so Aristotle's logic of terms, built around the categorical proposition of subject-predicate form, is related to modern quantificational logic. In both areas the work of the fourteenth century scholastics was that of revealing the inadequacy of the Aristotelian form of analysis, of suggesting in an ad hoc manner ways in which these limitations could be overcome while failing to generalize them into new foundations, and, in effect, drawing the curtain on a tradition that had outlived its usefulness for science without taking the further, step of replacing that tradition with a new and more adequate framework. In both cases, also, the further step was not taken until, centuries later, the language of mathematics replaced the qualitative language of ordinary experience in which ancient and medieval science had been expressed. There is, nevertheless, an interest and value attached to medieval logic which is not merely historical. In its attempt to formulate the semantical presuppositions of ordinary language medieval logic provided many suggestive analyses of problems that are now being encountered in contemporary investigations bearing on the semantical interpretation of branches of modern formal logic. T h e tradition of modern mathematical logic, until quite recently, paid little attention to the philosophical issues involved in the interpretation of its symbolic structure in terms of the concepts of meaning, denotation, and truth —much as Aristotle, eager to get on with his formulation of the syllogistic pattern of scientific demonstration as he conceived it, passed quickly over the semantical preliminaries to his logic of terms. What medieval logic has to contribute, to the further development and enrichment of modern logic, is this semantical bridge between the abstract, axiomatically derived, formal system of modern mathematical logic, and the concrete, empirically oriented forms in which 389
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natural languages exhibit the rational structure of experience on its phenomenological level. Where medieval logic, remaining within the framework of Aristotle's subject-predicate semantics, reached out for a more general and abstract foundation transcending the limitations of this scheme, so modern mathematical logic is reaching out for semantical interpretations that will exhibit the link to empirical language, and to this extent it can find much of interest in the explorations made by medieval logicians.
REFERENCES Selective Bibliography of Modern Text-Editions and Critical Studies Abelard, P. Peter Abelards Philosophische Schriften, ed. B. Geyer. (Beiträge z. Gesch. d. Phil. u. Theologie des Mittelalters, XXI, Münster i. W., 1919-1933). . Scritti Filosofici. Editio super Porphyrium, etc., ed. M. Del Pra. Milano, 1954. . Dialéctica, ed. L. M. de Rijk. Assen, 1956. . Abaelardiana Inédita, ed. L. Minio-Paluello. Roma, 1958. Adam of Balsham. Adam Balsamiensis Parvipontani Ars Disserendi, ed. L. Minio-Paluello. Roma, 1956. Bochenski, I. M. (I) "De consequentiis Scholasticorum earumque origine." Angelicum 15,1-18 (1938). (II) Formale Logik. Freiburg-München, 1956. Boehner, Philotheus. (I) "Ockham's Theory of Truth." Franciscan Studies 5, 138-161 (1945). . (II) "Ockham's Theory of Signification." Franciscan Studies 6, 143170 (1946). . (Ill) "Ockham's Theory of Supposition and the Notion of Truth." Franciscan Studies 6, 261-292 (1946). . (IV) Medieval Logic. Chicago, 1952. Buridanus, Joh. "Giovanni Buridano. Tractatus de Suppositdonibus," ed. Maria Eleina Reina. Rivista Critica di Storia della Filosofía XII, 175208 and 323-352 (1957). Dürr, Karl. (I) "Die Aussagenlogik im Mittelalter." Erkenntnis (Den Haag) 7,160-168 (1938). 390
The Medieval Contribution to Logic . (II) The Propositional Logic of Boethius. Amsterdam, 1951. Elie, H. (I) Le complexe significabile. Paris, 1936. Gilbertus, Porretanus. Liber de sex principiis, ed. A. Heyse. Münster i. W., 1953. Henry, D. P. (I) The De Grammatico of St. Anselm. Manchester, 1964. Joannes Saresberiensis. Metalogicon, ed. C. C. J. Webb, Oxford, 1929. Kneale, W . and M. (I) The Development of Logic. Oxford, 1962. Lukasiewicz, J. (I) "Zur Geschichte der Aussagenlogik." Erkenntnis S, 111-131 (1935). Matthews, Gareth B. (I) "Ockham's Supposition Theory and Modern Logic." The Philosophical Review, LXXIII, 1,91-99 (Jan. 1964). Moody Ernest A. (I) The Logic of William of Ockham. N. Y.-London, 1935. . (II) "Ockham, Buridan and Nicholas of Autrecourt." Franciscan Studies 1, 113-146 (1947). . (Ill) Truth and Consequence in Medieval Logic. Amsterdam, 1953. . (IV) "A Quodlibetal Question of Robert Holkot, O. P. on the Objects of Knowledge and Belief." Speculum, XXXIX, 1, 53-74 (Jan. 1964). . (V) Buridan and a Dilemma of Nominalism. Harry Austryn Wolfson Jubilee Volume. Jerusalem, 1965, 577—596. Ockham, Gulielmus. (I) Summa logicae, Pars Prima, ed. Ph. Boehner. St. Bonaventure, N. Y., 1951; Pars Secunda et Tertiae Prima, ibid., 1954. . (II) Tractatus de Praedestinatione et de Praescientia Dei et de Futuris Contingentibus, ed. Ph. Boehner. St. Bonaventure, N. Y., 1945. . (Ill) Expositionis artis logicae Prooemium et Expositio super librum Porphyrii de Praedicabilibus, ed. Ernest A. Moody. St. Bonaventure, N. Y., 1965. Petrus Hispanus. Summulae logicales, ed. I. M. Bochenski. Torino-Roma, 1947. Prior, A. N. (I) "Modality de dicto and Modality de re." Theoria (Lund) 18, 174-180 (1952). . (II) "The Parva Logicalia in Modern Dress." Dominican Studies 5, 78-87 (1952). . (Ill) "On Some Consequences in Walter Burleigh." The New Scholasticism 27 (1953). Shyreswood, William. (I) Die lntroductiones in Logicam des Wilhelm von Shyreswood, ed. M. Grabmann (Sitzungsberichte der Bayerischen Akad. der Wissenschaften, Phil.-hist. Abt., 1937, Hft. 10), München, 1937. . (II) "The Syncategoremata of William of Sherwood." ed. J. R. 391
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O'Donnell, C. S. B. (Medieval Studies 111, pp. 46 to 93), Toronto, 1941. Reina, Maria Eleina. (I) "Il Problema del Linguaggio in Buridano." Rivista Critica di Storia della Filosofia, XIV (4), 367-417, XV (2), 141-165 and XV (3), 238-264. Salamucha, J. (I) Die Aussagenlogik bei Wilhelm von Ockham (transl. from the Polish version published in 1935, by J. Bendiek). In Franziskanische Studien 32,97-134 (1950). Thomas, Ivor. "Saint Vincent Ferrer's De suppositionibus." Dominican Studies 5, 88-102 (1952). . (II) "Kilwardby on Conversion." Dominican Studies 6, 56-76 (1953). . (Ill) "Maxims in Kilwardby," Dominican Studies 7, 129-146 (1954).
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Galileo and His Precursors
i The name of Galileo Galilei is associated in history with events of profound significance to the modern world—with the birth of modern science, with the Copernican revolution, with the dethronement of Aristotle as supreme authority in the schools, and with the struggle against external restrictions on scientific inquiry. Galileo's greatness of character, and his intellectual honesty and devotion to the truth, make him a highly cherished symbol of the human achievements and values he represents. More than any other man of his age, he stands at the crossroads of history. Until the present century Galileo's originality, as creator of the dynamics that Newton brought to completion, has not been seriously questioned. When Ernst Mach published his Science of Mechanics in 1869, he stated without hesitation that "dynamics was founded by Galileo" and, with reference to the kinematic analysis of the accelerated motion of free fall, he said that "no part of the knowledge and ideas on this subject with which we are now so familiar, existed in Galileo's time, b u t . . . Galileo had to create these ideas and means for us."1 Soon after Mach wrote these words, the Notebooks of Leonardo da Vinci were edited and published, and it became evident that the problems of dynamics with which Galileo had occupied himself had been approached in a similar manner by Leonardo, who had used certain concepts, like that of impeto, in a way that foreshadowed Galileo's use of them. Similar ideas were then found in the work of Giambattista Benedetti, Nicolo Tartaglia, and Jerome Cardan. These findings 1 Ernst Mach, The Science of Mechanics, trans, by T . J. McCormack (Chicago, 1902), pp. 128, 133.
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Galileo and His Precursors suggested the possibility that all these men had some common source of this body of ideas, and Pierre Duhem, the distinguished French historian and philosopher of science, began to search for this source in early printed books on natural philosophy that had come off the presses in Leonardo's time, and which he might have read. Many of these books turned out to be works that had been written by scholastic teachers of natural philosophy at the universities of Paris and Oxford during the fourteenth century—Albert of Saxony, William of Heytesbury, Thomas Bradwardine, John Buridan, Richard Suiseth (the Calculator), and Nicole Orésme, among others. In studying these works Duhem became convinced that the fourteenth-century scholastics of the so-called Nominalist school had conceived and formulated a science of mechanics basically different from that of Aristotle, and strikingly similar in its essential principles to the mechanics of Galileo and his seventeenth-century contemporaries and successors. In a series of volumes published between 1905 and 1916 Duhem presented his findings and developed a radical reinterpretation of intellectual history which has come to be known as "Duhem's thesis." According to Duhem, the analysis of projectile motion and gravitational acceleration embodied in Galileo's Discourses and Mathematical Demonstrations Concerning Two New Sciences, involving the principle of inertia and the concept of force as that which changes the velocity and momentum of the body acted on, had been originated by John Buridan in fourteenth-century Paris, and, through the writings of Buridan's pupil Albert of Saxony, conveyed to Galileo, who then gave this dynamic theory a more precise mathematical formulation. Even the latter was said to be derived from another Frenchman, Nicole Orésme, who had in effect proved that the distances traversed by a body moving with uniformly accelerated velocity increase as the square of the times, by a geometrical form of proof later taken over by Galileo and used to establish the kinematic law of free fall. Galileo, according to Duhem, was the heir and the defender of this late medieval tradition, at a time when the Renaissance reaction against medieval culture in favor of a return to antiquity had restored the authority of Aristotle in the Italian universities. "When we watch the science of a Galileo triumph over the stubborn Peripateticism of a Cremonini," wrote Duhem, "we, being badly informed of the history of human thought, believe that we are witnessing the victory 394
Galileo and His Precursors of a young modern science over medieval philosophy... in reality, we are witnessing the triumph, long in preparation, of the science which was born at Paris in the fourteenth century, over the doctrines of Aristotle and Averroes which had been restored to honor by the Italian Renaissance."2 A more complete reversal of established views concerning the relation of seventeenth-century science to medieval scholasticism, and to the Italian Renaissance, is hard to imagine. The scientific revolution of the seventeenth century is said to have occurred in the fourteenth century, within the medieval schools rather than in opposition to them, and to have been obstructed, rather than inspired, by the Renaissance revival of learning. At stake here are not just a few facts of history, but the whole framework of interpretation of history. It is not surprising that Duhem's thesis has given rise, during the past thirty years, to vigorous defenses of the traditional view, and to laborious examinations of the evidence on which he based his claims, in an effort to show that his interpretation of this evidence, as well as the conclusions he drew from it, were not warranted. The controversies over Duhem's thesis have tended to be more philosophical than historical, more concerned with the meaning of the facts than with the facts themselves; yet much research into the medieval scientific tradition has been stimulated by Duhem's thesis, and the picture of scientific and intellectual history which we are able to paint today is neither simple nor free from controversy. The medieval precursors of Galileo are here to stay, and cannot be conjured away, though in what sense they merit the title Duhem bestowed on them is a subject of debate. And while most of us continue to believe that the real scientific revolution occurred in the seventeenth century rather than in the fourteenth, the question of what made it a scientific revolution no longer admits of a simple answer. In this paper I want to examine a rather widely accepted view of the relationship between Galileo's mechanics and that of his medieval predecessors, which may be briefly described as follows: The scholastics of the fourteenth century did, as Duhem claimed, develop a general dynamic theory constituting a science of mechanics different from that of Aristotle. This new dynamics, built around the so-called impetus-theory, became a more or less commonly accepted doctrine 2 Pierre Duhem, Etudes sur Léonard de Vinci, 3e Série: Les Précurseurs Parisiens de Galilée (Paris 1913), pp. v-vi.
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Galileo and His Precursors in the late medieval period, though a resurgent Aristotelianism reacted against it, in the Renaissance period, especially in the leading Italian universities. It was this fourteenth-century "impetus-dynamics" that Galileo took over and formulated in a systematic manner in his early work, De motu, written while he was still at Pisa. But after he went to Padua he became convinced of the inability of this theory to account for the facts, and he therefore made a fresh start on radically different principles, founding the inertial mechanics represented by his Discourses on Two New Sciences? This is a plausible account, able to give some satisfaction to all parties. The originality of the late scholastics, in creating a non-Aristotelian dynamics based on a few principles of high generality, is conceded; it is likewise conceded that this medieval mechanics formed a point of departure for Galileo's thought; but the traditional view, that modern classical mechanics was originated by Galileo on new foundations that he discovered for himself, is in no degree sacrificed by these concessions to his medieval predecessors. This solution of the historical problem has much to recommend it; it is relatively simple and clear-cut, even ecumenical in spirit. The philosophical perspective it embodies, and which it is intended to support, is one with which I have no quarrel. Its only defect, as far as I can see, is that it is not a true historical account. II The core of the problem, from the historical point of view, is what has come to be called, by historians of science, the medieval impetustheory. As generally expounded, this theory supposes that when a stone is thrown upward into the air, the action by which the thrower sets it in motion impresses on the stone a certain power, or ability, by which it continues to move upward after it has left the hand of the thrower; this "impressed power" (virtus impresso) grows continually weaker, becoming less and less able to overcome natural gravity, and thus the ascent is decelerated until gravity finally overcomes the impressed power, at which point the stone begins to fall, increasing its speed as it falls. Aristotle had felt forced to account for such upward motions in terms of propulsion by the air, since he would not 3 Cf. Alexandre Koyre, Etudes Galileennes (Paris, 1939), I, 10 and passim; A. R. Hall, The Scientific Revolution (London, 1956), chaps. 1 and 3; and Anneliese Maier, Die Vorläufer Galileis im 14. Jahrhundert (Rome, 1949), pp. 1-6, 132— 154.
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Galileo and His Precursors admit that a body could move against its nature unless it was propelled by some body in contact with it. The implausibility of Aristotle's explanation was pointed out by his Alexandrian successors, and both Hipparchus and John Philopon proposed the alternative explanation of propulsion by an impressed power. This theory of projectile motion, taken in itself, is not particularly medieval; it was espoused by Greeks, Muslims, and Latin scholastics, as well as by Leonardo da Vinci, Benedetti, and Galileo himself. In this general sense it is not so much a theory, or explanation, of projectile motion, as a rejection of Aristotle's mechanical explanation in terms of propulsion by the physical medium. In the late thirteenth and early fourteenth centuries a few theologians in Paris discussed the projectile problem and suggested that the original mover of the projectile imparts to it the "impressed virtue" (vitus impressa) which remains in it for a short time, then fades away because of being separated from its source. In a manuscript dated 1323 a rather full presentation of this theory, by a theologian named Franciscus de Marchia, is found; it contains various arguments against Aristotle's theory, which were used by later writers down to Galileo himself; but it makes clear that the impressed power that moves the projectile is an essentially temporary quality that is self-dissipating. The word impetus, incidentally, was scarcely ever used as a name for this impressed power by any of the Latin writers down to, and including, Franciscus de Marchia. It was introduced as a technical term by John Buridan, a teacher on the Arts Faculty of the University of Paris from around 1320 to 1358, in connection with an explanation of projectile motion which was significantly different from that of Marchia and the earlier writers. After rejecting Aristotle's theory by the usual arguments, Buridan said that the projectile, on leaving the hand of the thrower, continues to move in the direction in which it is thrown because the thrower, by setting it in motion, imparts to it an impetus that keeps it moving in that direction until the resistance of the air and the opposed force of the body's gravity overcome the impetus. Impetus is described, quantitatively, as proportionate to the velocity and to the quantity of matter (quantitas materiae) of the body. But the feature of Buridan's theory which makes it decisively different from that of Marchia is his statement that impetus is a condition of permanent nature, such that if no opposed or resisting forces operated to diminish it, it would 391
Galileo and His Precursors remain unchanged and keep the body moving indefinitely. Since in the terrestrial regions forces of resistance are encountered, and since in heavy and light bodies there are natural tendencies to move toward their places of natural rest, the impetus is de facto overcome, and bodies set in motion in this way do not keep going beyond a limited time. This is not because the impetus is consumed by the motion itself, however, but only because it is exhausted by the opposed forces of gravity and air resistance. In the celestial bodies, on the other hand, no such resistances or opposed forces are encountered; so Buridan says, subject to correction by the theologians, that "it could be said that when God created the celestial bodies, He set them in motion in the way that pleased him; and then, from that impetus which he gave them, they are moved to this day, since that impetus is neither corrupted nor diminished, because the celestial bodies encounter no resistance."4 It seems obvious that Buridan's concept of impetus, as used in his explanation of projectile motion and of the everlasting rotation of the celestial spheres, differs from the earlier concept of a self-consuming impressed virtue in much the same way that the concept of impeto which Galileo employed in his mature dynamics differed from the concept of impressed force which he had used in his youthful work De motu. It is customary, indeed, to say that when Galileo gave up the assumption of self-weakening of the impressed force and ascribed the retardation of the projectile solely to the resisting forces of the medium and of the gravity of the projectile, that he transformed the "impressed force" theory into the principle of inertia.5 4 Joannis Buridani quaestiones de caelo et mundo. Lib. II, qu. 12, ed. by E. A. Moody (Cambridge, Mass., 1942), pp. 180-181. The relevant texts in which Buridan's theory is presented are given in accurate translations by Marshall Clagett, The Science of Mechanics in the Middle Ages (Madison, 1959), pp. 505-582, along with a very fine account of the history of the problems of projectile motion and free fall. 5 Cf. A. R. Hall, The Scientific Revolution (Beacon Press ed., 1956), pp. 86-87 Speaking of the law of inertia, Hall says "it was derived from the consideration of motion in a resisting medium: if the impetus of a body is expended in overcoming the resistance, then in the absence of resistance its impetus and velocity will remain eternally constant." Cf. also Ernst Mach, The Science of Mechanics: Supplement to the Third English Edition, trans, by Philip E. B. Jourdain (Chicago, 1915), pp. 25-26: "But it was only when Galileo gave up this supposition of a gradual and spontaneous decrease of the impressed force and reduced this to resisting forces, and investigated the motion of falling experimentally and without taking its causes into consideration, could the laws of the uniformly accelerated motion of falling appear in a purely quantitative form."
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Galileo and His Precursors Buridan applied his concept of conserved impetus and velocity to the problem of free fall by supposing that the effect of the gravity of the falling body is that of producing increments of impetus and velocity in the body continuously with the time, and since these increments of impetus and acquired velocity are retained and accumulated througout the time of fall, the movement is one of continuous acceleration. This analysis, though compatible with that given by Galileo in his Two New Sciences, is entirely different from the explanation of free fall he upheld in his early Pisan work De motu. In that work, he assumed that the effect of gravity, taken in itself, is a downward motion at constant velocity, and that the acceleration observed in falling bodies is owing only to the self-weakening of the residual "impressed force" derived from the agency that raised them, or held them, above the ground. If Galileo's earlier Pisan dynamics reflected a medieval tradition, it was not the impetus theory of Buridan that it reflected, but the "impressed virtue" theory of Marchia which was similar to that of Philopon and Hipparchus. And if Buridan's explanation of free fall influenced Galileo at any time, this could only have been during his Paduan period when he gave up his earlier theory and began to analyze free fall in terms of cumulative retention of the increments of impetus given to the body by its gravity.6 It was on the basis of the impetus theory of Buridan, and not on the basis of the theory of a self-consuming impressed force such as had been espoused by Marchia, Philopon, and Hipparchus, that Duhem made his claim that the inertial dynamics of Galileo had been originally conceived at Paris in the fourteenth century. Duhem's thesis is not refuted, therefore, by showing that the virtus impressa theory of Hipparchus, Philopon, and Marchia, which Galileo adopted in his early De motu and later abandoned, was incompatible with the inertial concept of impeto at which Galileo arrived in his later analysis of projectile movement and free fall. It would have to be shown that Buridan's concept of impetus, and his analysis of projectile 6 Cf. my study, "Galileo and Avempace: The Dynamics of the Leaning Tower Experiment," Journal of the History of Ideas, XII, 163-193 and 375—422 (April and June, 19Î1), for an analysis of Galileo's Pisan dynamics and its medieval antecedents. Koyré, op. cit., I, 54-73, expounds this early theory of Galileo in similar manner, but supposes it to represent what he calls the "physique de Yimpetus, inaugurée, comme toute chose, par les Grecs, mais élaborée surtout au cours du quatorzième siècle par l'école parisienne de Buridan et de Nicole Orêsme" (I, 10).
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Galileo and His Precursors motion and of free fall, is incompatible with that of Galileo's mature dynamics. I do not think that this can be done, and the strenuous efforts that have been made to show that Buridan's impetus theory did not really differ from the earlier impressed force theory seem to me, one and all, to beg the question.7
Ill T o show that Buridan's analysis of projectile motion and free fall is formally compatible with the analysis of these phenomena given by Galileo in his Two New Sciences, and formally incompatible with the analysis given in his early work De motu, does not establish Duhem's claim that modern inertial dynamics was created by Buridan and his fourteenth-century contemporaries and successors. What it does show, I believe, is that there was not one common medieval doctrine that can be associated both with Galileo's early dynamics and with the "Parisian dynamics" developed by Buridan. Except for his use of 7 C f . Koyre, op. cit., II, 12-13, 19-20, for such arguments. Anneliese Maier, Die Vorläufer Galileis im 14. Jahrhundert (Rome, 1949), and Zwei Grundprobleme der scholastischen Naturphilosophie (Rome, 1951), has argued the question at length. Leaving aside the psychological and ontological arguments, which are not at issue here, Miss Maier argues that an inertial interpretation of Buridan's impetus is impossible, at least in the instance of the projectile and free fall problems, because even if abstraction is made of resistance by the medium and of opposed gravity, there remains an intrinsic inclinatio ad quietem, or tendency to come to rest, distinct from the gravity (or levity) of the body. Therefore, despite Buridan's apparent statement that if there were no resistance by the medium or by the opposed force of gravity the projectile would keep moving ad infinitum, Miss Maier contends that Buridan did not believe that the impetus would endure forever in the absence of these resisting forces, but that it would be used up by the inclinatio ad quietem inherent in every material body irrespective of its substantial form or nature. Now, I have encountered this phrase inclinatio ad quietem in Oresme, who says that the celestial spheres do not resist the intelligences that move them with any inclination to the opposed (rotational) motion or with any inclinatio ad quietem. But I have searched all of Buridan's texts relevant to the question, and have never found him using this phrase or positing any such inclinatio ad quietem over and above the natural gravity of the body; and I have searched through Miss Maier's books, in which she speaks of this inclinatio ad quietem as something assumed by Buridan, and have found no citation or quotation of Buridan's texts, to support what she says, anywhere in these books. What I have found in Buridan's writings, on the other hand, is the repeated assertion that "prime matter" does not resist motion, and this would seem to indicate that the only internal resistance posited by Buridan is that which is consequent on the substantial form of the body—namely, its gravitas or levitas.
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Galileo and His Precursors certain arguments against Aristotle's theory that projectiles are moved by the air, which had been used by practically everyone who discussed Aristotle's Physics from the fourteenth to the sixteenth century, there is no evidence in Galileo's De motu of any awareness of the ideas in mechanics that were first developed in the fourteenth century—no awareness of Bradwardine's exponential reformulation of Aristotle's "law of velocities," no awareness of the kinematic analysis of uniformly accelerated motion developed by Heytesbury and Swineshead at Oxford, no awareness of Oresme's geometrical formulation of this Mertonian kinematics, and no awareness of the dynamic analysis of projectile motion and free fall proposed by Buridan. Galileo's early Pisan dynamics cannot be characterized as a reflection, and initial tryout, of fourteenth-century mechanics. There is evidence, on the other hand, in the Dialogues Concerning the Two Chief World Systems, and in the Discourses and Mathematical Demonstrations Concerning Two New Sciences, of familiarity with ideas originated in the fourteenth century. In these dialogues such ideas are frequently put in the mouth of Sagredo, who seems to have been portrayed by Galileo as representative of the "tradition of the moderns," in contrast to Simplicio, who represents the reactionary Aristotelianism that had become dominant at Padua and other Italian universities since the early part of the sixteenth century. In the Dialogues, for example, Salviati asks Sagredo if he is ready to concede that a ball, in falling, continuously gains greater impetus and velocity. Sagredo immediately agrees to this, and then, when asked if the acquired impetus would suffice to lift the body to the original height, he says that it would, if not impeded by an external resistance. Sagredo then gives the example of a ball, dropped into a hole perforating the earth through its center, which acquires enough impetus in falling to the center to bring it to the surface at the other side, and he compares this motion to that of a pendulum which, if not impeded by friction, would oscillate forever. These examples, which clearly presuppose Buridan's conception of impetus as self-conserving in the absence of resistances, go back to Oresme and Albert of Saxony, though no doubt Sagredo could have derived them from a later source. At another place in the Dialogues there seems to be a very clear reference to a discussion found in Albert of Saxony's questions on the De caelo, where Sagredo remarks that the mast of a ship travels further in the same time than the hull of the ship, because it traverses a greater arc. 401
Galileo and His Precursors Here Simplicio astonishes his friends by saying, "And thus when a man goes walking, his head travels farther than his feet?," which happens to be a word for word quotation from Albert of Saxony's question 27 on the second book of the De caelo. The surprise at Simplicio having made this remark is intended, presumably, to indicate that the Paduan Aristotelians of strict observance, represented by Simplicio, would not have been expected to know the writings of the fourteenth-century scholastics, who were regarded by them as corruptors of Aristotelian doctrine.8 The most striking indication of fourteenth-century influence on Galileo's mature mechanics is provided by the Latin treatise De motu locali incorporated in Galileo's dialogue on Two New Sciences, Third Day, in which the statement and proof of the kinematic law of uniformly accelerated motion is given. At the beginning of this treatise Galileo proudly states that although others had observed that the natural motion of freely falling bodies is continuously accelerated, the extent to which this acceleration occurs had not been determined, and, he adds, "so far as I know, no one has yet pointed out that the distances traversed, during equal intervals of time, by a body falling from rest, stand to one another in the same ratio as the odd numbers beginning with unity."9 This statement certainly gives the impression that what Galileo takes chief credit for is the determination of the relation between distance traversed and time elapsed in uniformly accelerated motion, and not merely for establishing that free fall is an instance of uniformly accelerated motion. Yet it is only the latter that he can rightly claim, since the relation of distances to times, in uniformly accelerated motion as such, had been determined in the fourteenth century by Heytesbury, Swineshead, Dumbleton, and Oresme, by means of the so-called Mertonian mean-speed law. Galileo uses this same law as his own basic theorem, and proves it by the geometrical method used by Oresme. Now this Mertonian theorem, which states that the distance traversed by a body uniformly accel8 C f . Galileo Galilei, Dialogues Concerning the Two Chief World Systems, trans, by Stillman Drake (Berkeley and Los Angeles, 1953), pp. 22-23 and 173— 174. A note by the translator suggests that Simplicio drew his remark about a man's head moving faster than his feet from the Enciclopedia Amplissrma of Clement Clementi (Rome, 1624); but its origin is in Albert of Saxony's Quaestiones de caelo et mundo, Lib. II, qu. 27 (Paris, 1492). 9 Galileo Galilei, Two New Sciences, trans, by Crew and de Salvio (Dover Publications, N e w York, 1914), p. 153.
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erated from rest is equal to the distance that would be traversed by a body moving for that length of time at a constant velocity equal to one-half the terminal velocity of the accelerated motion, was widely known in the sixteenth century, appearing in at least seventeen printed books current at the time.10 It is a curious paradox that Galileo's statement and proof of the kinematic law of uniformly accelerated motion, which provided the means for a quantitative formulation of the dynamics of free fall, and which is regarded as the distinctively modern approach to dynamics which makes Galileo's science toto caelo different from the qualitative physics of earlier times, should turn out to contain the most definitely identifiable use of fourteenthcentury materials in Galileo's work. Yet it is by recognizing this fourteenth-century influence on Galileo's thinking that problems which have long puzzled students of Galileo's work can be resolved. Why was it, for example, that in 1604 and for five or six years thereafter Galileo felt certain that the distances traversed in uniformly accelerated motion increase as the square of the times, and yet took it as self-evident that the velocity increases in direct proportion to the distance traversed in such a motion? Why, for that matter, did Descartes also hold to these incompatible beliefs? And why did they think that they could derive the s = Vzat2 law from the assumption that velocity is a function of distance traversed? T o suppose that Galileo had determined the correct law experimentally, while making the assumption that velocity is proportional to distance because as a geometrician he thought of motion in spatial rather than temporal terms,11 is not a convincing explanation; it would take an extremely delicate experiment to establish the law by measurement alone, and resort to a psychological explanation to account for Galileo's association of increase of velocity with increase of distance, rather than time, seems too much like a last resort. If, however, we suppose that Galileo had been led to reformulate his dynamic analysis of free fall in terms of conserved impetus and velocity, by reading Albert of Saxony's writings in which Buridan's analysis was presented, he would at the same time have encountered Albert's kinematic interpretation of this analysis according to which the velocity increases in proportion to the distance of fall. In taking 1 0 Cf. Clagett, op. cit., p. 414, and, for the full history of the medieval background of this kinematic law, pp. 255-418. 1 1 This is suggested by Koyre, op. cit., II, 21.
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Galileo and His Precursors over the dynamic analysis Galileo may well have taken this kinematic interpretation for granted as part of the theory. On the other hand, the Mertonian theorem, which correctly describes the relation of distance to time in uniformly accelerated motion, was well known in Galileo's time, although the complicated arithmetical type of proof used by the Mertonian authors was not so well known and certainly not so easy to understand. As many incidental remarks in Galileo's writings indicate, he was quite ready to concede that earlier thinkers had formulated many true conclusions concerning the motions of bodies, but without establishing them by mathematically cogent demonstrations.12 In seeking to provide such a demonstration, Galileo had available the geometrical form of proof used by Oresme, John of Casali, and later authors to show that the latitude of a quality whose intensity is uniformly nonuniform in relation to its extension is measured by its mean degree. Such uniformly nonuniform qualities were represented by a right triangle whose altitude at each point along the base represented the degree of intension of the quality at that point, and whose base represented the "longitude" or "extension" over which these qualitative intensions are distributed. This base or longitude could represent, equally well, a spatial distribution of the quality, such as degrees of heat along the length of a poker cold at one end and hot at the other, or the time during which a quality was increased from zero intensity to a maximum intensity by a motion of alteration. The meandegree law would hold for either instance. Shifting to local motion, the uniformly nonuniform acquisition of a terminal velocity becomes a uniform acceleration, and the same triangular representation was used, with the altitude representing the degree of velocity acquired at each point or successive part of the motion represented by the base or "longitude"; the area of the triangle was then regarded as representing the summation of the velocities corresponding to each point of the base line. It was then easy to show that this total velocity (velocitas totalis) would be equaled by a motion at uniform velocity represented by a rectangle whose base is equal to that of the triangular representation, but whose altitude corresponds to that which bisects the base of the triangular figure, and which is therefore one-half of the vertical side of the triangular figure. Taking the "total velocity" as measure of the distance traversed in the whole movement, the Mer12
Cf. his remarks in the Discorsi e dimostrazioni, ed. nazionale, p. J4. 404
Galileo and His Precursors tonian theorem follows. But it is not immediately evident whether the summation of velocities is a time integral or a space integral. Since this form of proof had been given, in the first instance, as a way of equating nonuniform distribution of qualitative intensities with uniform distributions over the same extension, it was natural to construe the qualitas totalis, and derivatively the velocitas totalis, as a space integral. This is precisely what Galileo did when he attempted to use this method of proving the Mertonian theorem from the supposedly evident principle that velocity in uniformly accelerated movement increases as a function of distance; a principle that seemed evident to Galileo because the dynamic theory of free fall in terms of successive increments of conserved impetus and velocity had been presented to him in this interpretation by Albert of Saxony. It was I. B. Cohen who proposed this explanation of Galileo's ingenious but fallacious attempt to derive the correct kinematic law from the false assumption that velocity increases with distance of fall, given in his letter to Sarpi in 1604; and the fact that Galileo used the terminology of the medieval theory of intension and remission of qualities, such as "degree," "extension," "total velocity" (la summa di tutta la velocità), even after he had corrected his error, is good confirmation of this explanation.13 If this explanation is accepted, it becomes quite easy to understand why Galileo believed, in all honesty, that he was the first to demonstrate that in the free fall of bodies the distances traversed increase with the square of the times. He had already associated the dynamic analysis given by Albert of Saxony with the Mertonian mean-speed law, but had assumed that his medieval predecessors had sought to prove this law, as he himself for a number of years had tried to prove it, from the assumption that velocity increases as a function of distance of fall. But when he finally saw that it could not be proved in this way, and that his predecessors, as he thought, had never realized that the velocity must increase as a function of the time of fall, he naturally felt that he was the first to have achieved a correct demonstration and a true analysis of the way in which gravitational acceleration takes place.
1 3 Cf. I. B. Cohen, "Galileo's Rejection of the Possibility of Velocity Changing Uniformly with Respect to Distance," Isis, Vol. XXVII, pt. 3, no. 149, pp. 231235. On Galileo's terminology, cf. Clagett, op. cit., pp. 414-416.
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Galileo and His Precursors IV Reverting now to the original question of the historical relationship between the work done in mechanics by the fourteenth-century scholastics and the development of Galileo's mechanics, I would make the following emendations to what I described earlier as a widely accepted view. Although it is correct to say that Galileo's Pisan dynamics reflected a medieval tradition—namely that of the self-consuming impressed force as explanatory of projectile motion—it is not correct to say that it reflected the impetus dynamics of Buridan and Albert of Saxony, or for that matter of any of the other distinctively fourteenth-century contributions to mechanics. One early medieval tradition that it did reflect, and one of lasting importance in the development of Galileo's own mechanics, was that of the Muslim philosopher Ibn-Badja, known as Avempace, whose view that resistance by a medium is not an essential factor or condition of the motion of terrestrial bodies was adopted by Galileo at Pisa, and never abandoned. It was this that enabled Galileo to generalize Buridan's impetus theory and transform it into a general inertial dynamics.14 Second, it seems evident to me that during his Paduan period Galileo •was influenced by ideas that had been developed in the fourteenth century at Paris and at Oxford—by Buridan's analysis of projectile motion and free fall in terms of conserved impetus and velocity, by the Mertonian kinematic analysis of accelerated motion, by the method of graphic representation of qualitative intensions and extensions used by Oresme and Casali, and very likely by the fourteenth-century treatments of infinity and continuity which were closely associated with these other contributions. In what form, or through what books, these ideas were conveyed to Galileo, are questions that, if answerable in whole or in part, would cast a good deal of light on the way Galileo's thinking developed. If historians of science had given more time to historical research on this problem, instead of engaging in a priori debates over the validity or invalidity of Duhem's thesis, better insight into the nature of Galileo's scientific achievements might well have been gained. 14 Cf. my study, "Galileo and Avempace," Journal of the History of Ideas, Vol. XII, nos. 2-3, pp. 163-193, 375-422.
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Galileo and His Precursors These conclusions may seem to support Duhem's thesis. T o the extent that Duhem claimed that the ideas of the fourteenth-century Parisians and Mertonians played an important part in the development of Galileo's mechanics, his thesis is supported. But the further claim that the modern science of mechanics was "founded" two hundred years before Galileo's birth, is certainly mistaken. N o t because the fourteenth-century scholastics did not provide ideas and some of the mathematical means Galileo was able to use, and in fact did use, in building his new science, but because in the fourteenth century these ideas and means were not so used. In their fourteenth-century occurrence these ideas were scattered superstructures erected on the edifice of Aristotelian physics and cosmology, each part added b y a different person or group in isolation from the other parts, so that they were never put together, and never made into a foundation for a new science, b y any medieval scholastic. Bradwardine and his Mertonian disciples, though quite original in grasping the notion of instantaneous velocity and in achieving an abstract mathematical analysis of uniformly accelerated motion, had no sympathy at all for the dynamic analysis of projectile motion and free fall that was developed b y Buridan; their dynamics was that of Aristotle and Averroes. Buridan, whose impetus concept, as used in analyzing projectile motion and free fall, had the real potentiality of being generalized and made the foundation of a new dynamics, did not generalize it. H e made no effort to eliminate the incoherence between his impetus theory and the Aristotelian doctrine that resistance b y the medium is essential to the occurrence of motion b y terrestrial bodies. This Aristotelian doctrine he accepted, and along with it the Aristotelian "law of velocities" as it had been reformulated b y Bradwardine. 15 W h y these fourteenth-century scholastics did not exploit the new ideas they had worked out for special cases, and built a new science that would replace the Aristotelian physics and cosmology, may well be asked. I would suggest that, as teachers in universities whose philosophical curriculum was built out of the books of Aristotle, they had neither 15 Cf. Clagett, op. cit., pp. 421-503, concerning Bradwardine's peripatetic dynamics and his reformulation of Aristotle's law of velocities. Duhem op. cit., pp. 432-439, describes the rejection, by the Oxford scholastics, of the impetus dynamics. Buridan's acceptance of the Aristotelian thesis that resistance by a medium is essential to motion at finite velocity, by terrestrial bodies, is evident in his Quaestiones in libros physicorum (Paris, 1509), fols. Ixxiii recto, Ixxvi verso.
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Galileo and His Precursors opportunity nor motivation to overhaul the ship on which they were sailing; their job was to make the best sense they could out of their textbooks, not to abolish them. From these considerations I draw my third conclusion that, contrary to widely accepted opinion, there was no such thing as a fourteenth-century science of mechanics in the sense of a general theory of local motion applicable throughout nature, and based on a few unified principles. By searching the literature of late medieval physics for just those ideas and those pieces of quantitative analysis that turned out, three centuries later, to be important in seventeenth-century mechanics, one can find them; and one can construct, as Duhem did, a "medieval science of mechanics" that appears to form a coherent whole and to be built on new foundations replacing those of Aristotel's physics. But this is an illusion, and an anachronistic fiction, which we are able to construct only because Galileo and Newton gave us the pattern by which to select the right pieces and put them together. It is a fiction, not because these isolated theories and pieces of analysis conceived in the fourteenth century as a means of resolving difficulties in Aristotle's phyiscs were not capable of being made into foundations of a new mechanics. It is a fiction simply because in the fourteenth century these ideas were not made into fundamental principles of a new science, were not brought together into a coherent unity, and were not generalized to bring about abandonment of incompatible doctrines accepted from Aristotle. It was Galileo who did these things, and it was this doing that merits him the title he has held for three centuries, that of founder of modern mechanics. He did not create his mechanics (nor that of Newton as some seem to suppose) out of thin air, and to this extent Duhem is certainly right. But he conceived the kind of science that became classical mechanics, using the materials available to him and building his new science with the foundations in the right place. This his medieval predecessors did not do, and did not even try to do. In this achievement Galileo had no precursors among his medieval predecessors.
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William of Ockham
Although William of Ockham was the most influential philosopher of the fourteenth century, very little is known, with certainty, concerning his life. Apparently he was born sometime between 1280 and 1290 at the village of Ockham, in Surrey, near London. Entering the Franciscan order at an early age, he commenced his course of theological study at Oxford in 1309 or 1310, and completed the requirements for the degree of master of theology with the delivery of his lectures on Peter Lombard's Book of Sentences in 1318-1319, or, at the latest, 1319-1320. Although an old tradition indicated that he studied under Duns Scotus, it seems unlikely that he did so, since Duns Scotus left Oxford at the beginning of the century and died in 1308. Ockham's writings show intimate familiarity with the teachings of Scotus, but this is explained by the dominant position Scotus had acquired at Oxford, particularly within thé Franciscan order. Ockham's lectures on the Sentences made a profound impression on the students of theology at Oxford, but his new way of treating philosophical and theological questions aroused strong opposition by many members of the theological faculty. Normally the completion of his lectures on the Sentences, which gave Ockham the status of a baccalaureus formatus or inceptor, would have been followed by award to him of a teaching chair in theology. The granting of his teaching license was prevented by the chancellor of the university, John Lutterell, who in 1323 went to the papal court at Avignon to present charges against Ockham of having upheld dangerous and heretical doctrines. Because Ockham's academic career was thus interrupted while he was an inceptor awaiting award of the teaching 409
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license, he came to be known as "the venerable inceptor"—a title later misconstrued as meaning "founder of nominalism" (inceptor scholae nominalium). Ockham was summoned to Avignon in 1324 to answer the charges against him, and he remained there four years, awaiting the outcome. A commission of theologians appointed by Pope John XXII to examine Ockham's writings submitted two lists of suspect doctrines in 1326, but there is no evidence of any final action having been taken on the charges which, in any case, were relatively mild. Despite the lack of a teaching chair, Ockham was extremely active during these years in developing his theological and philosophical positions, writing treatises and commentaries on logic and physics, a variety of treatises on theological questions, and an important series of quodlibetal questions that, presumably, he debated orally at Oxford or at Avignon. In 1327, while at Avignon, Ockham became involved in the dispute then raging over the question of apostolic poverty, in which the general of the Franciscan order, Michael of Cesena, took a position opposed by the pope. Asked to study the question, Ockham found that a previous pope, Nicholas III, had made a pronouncement that fully supported the position of Cesena and of the majority of the Franciscans. When this controversy reached a critical stage in 1328, and it became evident that John XXII was about to issue an official condemnation of the position held by the Franciscans, Cesena and Ockham, along with two other leaders of the Franciscan opposition, fled from Avignon and sought the protection of Emperor Louis of Bavaria, who had repudiated the authority of the Avignon papacy in connection with the issue of succession to the imperial crown. Immediately after their flight from Avignon, Ockham and his companions were excommunicated by the pope for their refusal to submit to his authority. Under the emperor's protection Ockham took up residence in Munich and devoted his full energies to writing a series of treatises on the issue of papal power and civil sovereignty, in which he held that John XXII had forfeited his right to the papal office by reason of heresy. When John XXII died in 13 34, Ockham continued his polemic against the succeeding Avignon popes until 1347, when Louis of Bavaria died and the antipapal position became a lost cause. There is evidence that Ockham at that time sought reconciliation with the papal authority and with the rest of his own order, but the outcome is unknown. It is believed that he died in 1349, a victim of the Black Plague 410
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that, in the middle of the fourteenth century, took the lives of most of the intellectual leaders of northern Europe and played a major part in bringing about the cultural decline that lasted for more than a century. Ockham's writings fall into two distinct groups associated with the two different periods of his career. All of the political and polemical treatises directed against the Avignon papacy were written during his residence in Munich, between 1333 and 1347. Of these treatises many are solely of historical interest; but the lengthy Dialogus Inter Magistrum et Discipulum, written between 1334 and 1338, the Octo Quaestiones Super Potestate ac Dignitate Papali, written in 1340, and the Tractatus de Imperatorum et Pontificum Potestate, composed around 1347, present Ockham's philosophy of church and state and convey his deep-rooted convictions concening the religious mission of the church. The nonpolitical writings that embody Ockham's distinctive contributions to philosophy and theology were probably all written while he was at Oxford and at Avignon, between 1317 and 1328-. The earliest of these include the lectures on the Sentences, a lengthy exposition of Aristotle's Physics extant only in manuscript form, and literal commentaries on Porphyry's Isagoge and on Aristotle's Categoriae, De Interpretation, and De Sophisticis Elenchis; the first three of the commentaries were published at Bologna in 1496 under the title Expositio Aurea ... Super Artem Veterem ("Golden Exposition . . . of the Ancient Art"). Ockham's most important work on logic, completed before he left Avignon, was a systematic treatise entitled Sumrna Logicae, extant in several printed editions. An incomplete Summulae in Libros Physicorum (also given the title Philosophia Naturalis) contains an independent treatment of the subjects dealt with in the first four books of Aristotle's Physics, and was printed in several editions, beginning in 1495. In manuscript form only there is a work entitled Quaestiones Super Libros Physicorum, which was probably one of his later writings; it covers, in the form of disputed questions, most of the topics treated in his earlier literal commentary on the Physics but reflects some changes in his views that occurred after the earlier work had been written. Two short compendia of logic, each extant only in a single manuscript version, are believed to be authentic works of Ockham, but they add nothing significant to the doctrines of his Sumrna Logicae. 411
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Of Ockham's theological writings the lectures on the first book of the Sentences, known as the Ordinatio because Ockham revised and edited them for circulation, are of primary importance. They were printed at Lyons in 1495, along with Ockham's lectures on the other three books of the Sentences. The latter are called the Reportatio because the text is derived from stenographic versions of the lectures as they were delivered. A modern critical edition of both parts of these lectures on the Sentences is very much neeeded. Of comparable importance for the understanding of Ockham's philosophical and theological doctrines are the quodlibetal questions, printed at Paris in 1487 and again at Strasbourg in 1491 under the title Quodlibeta Septem. Three other certainly authentic theological treatises, composed during the Oxford-Avignon period, are the Tractatus de Corpore Christi and Tractatus de Sacramento Altaris, which have been regularly printed together under the second of these titles, and the Tractatus de Praedestinatione et de Praescientia Dei et de Futuris Contingentibus, of which a modern edition, edited by Philotheus Boehner, was published in 1945. The 1495 Lyons edition of Ockham's theological works includes Centiloquium Theologicum, whose authenticity has been questioned by many scholars but without decisive evidence. In describing the philosophical doctrines of Ockham, use will be made chiefly of the Commentary on the Sentences, the Summa Logicae, and the Quodlibeta Septem. Ockham's major contributions to the development of late medieval and early modem philosophy were in the areas of epistemology, logic, and metaphysics. His approach to these problems and his concern with them were those of a scholastic theologian, as had been the case with Thomas Aquinas, Duns Scotus, and other leading scholastic thinkers of the thirteenth century. The basic problem of scholastic theology since the beginning of the thirteenth century had been that of finding a means of accommodating the philosophical system of Aristotle within the dogmatic framework of Christian doctrine. To achieve such an accommodation was a philosophical task because no alteration in the articles of the faith could be allowed, and consequently all elimination of contradictions had to be achieved by internal criticism or reinterpretation of the philosophical assumptions and arguments of Aristotle. Aquinas had sought to achieve an essentially external accord between natural philosophy and Christian theology, such as would leave the Aristotelian system internally intact. 412
William of Ockham The Franciscan theologians, from St. Bonaventure to Duns Scotus, had considered this inadequate and had sought to achieve the required integration of philosophy and theology by exploiting the more Platonic elements of the Aristotelian system, much as the Greek Neoplatonists and the Muslim philosopher Avicenna had done. All of the thirteenth-century syntheses of philosophy and theology involved, in one form or another, the metaphysical and epistemological doctrine of realism—the doctrine that the human intellect discovers in the particulars apprehended by sense experience an intelligible order of abstract essences and necessary relations ontologically prior to particular things and contingent events and that from this order the intellect can demonstrate necessary truths concerning first causes and the being and attributes of God. Ockham's significance, both as a theologian and as a philosopher, lay in his rejection of the metaphysical and epistemological assumptions of medieval realism, and in his reconstuction of the whole fabric of philosophy on the basis of a radical empiricism in which the evidential base of all knowledge is direct experience of individual things and particular events. The counterpart of this epistemological empiricism was the nominalistic analysis of the semantical structure and ontological commitment of cognitive language that Ockham developed in his logical writings. Ockham's empiricism was not phenomenalistic or subjectivistic, and it could be called a realistic empiricism according to a modern usage of "realism"; it presupposed and was based on the principle that the human mind can directly apprehend existent individuals and their sensible qualities, and that it can also directly apprehend its own acts. Insofar as Ockham is called a nominalist, his doctrine is not to be construed as a rejection of any ontological determination of meaning and truth, but rather as an extreme economy of ontological commitment in which abstract or intensional extralinguistic entities are systematically eliminated by a logical analysis of language. The principle of parsimony, whose frequent use by Ockham gained it the name of "Ockham's razor," was employed as a methodological principle of economy in explanation. He invoked it most frequently under such forms as "Plurality is not to be assumed without necessity" and "What can be done with fewer [assumptions] is done in vain with more"; he seems not to have used the formulation "Entities are not to be multiplied without necessity." The principal use made by Ock413
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ham of the principle of parsimony was in the elimination of pseudoexplanatory entities, according to a criterion he expresses in the statement that nothing is to be assumed as necessary, in accounting for any fact, unless it is established by evident experience or evident reasoning, or is required by the articles of faith. As applied by Ockham, the principle of parsimony resulted in an empiricist criterion of evidence that left little room for a natural theology. But since it also reduced physics and cosmology to the status of positive sciences without metaphysical necessity, it left room for a positive theology based on revelation and faith that could no more be refuted than it could be demonstrated by any necessary reasons or observational evidence. Moreover, this positive theology, in which God is conceived as the omnipotent creator of all finite things whose creative and causal action is wholly free and unnecessitated, provided an indirect justification of Ockham's philosophical empiricism, since it demanded a conception of the world of created things as radically contingent in both their existence and their interaction. Ockham made full use of the doctrine of divine omnipotence as an ad hominem argument against those who sought to discredit his philosophical doctrine on theological grounds; philosophically, however, the doctrine was equivalent to the principle that whatever is not self-contradictory is possible, and that what is actual, within the range of the logically possible, cannot be established by reason alone but only by experience. Ockham's epistemology and metaphysics were designed to resolve a basic problem that the Scholastics had inherited from the Greek philosophical tradition and that may be summed up in the paradoxical thesis that the objects of thought are universal, whereas everything that exists is singular and individual. Seeking to overcome this gap between the intelligible and the existent, the earlier Scholastics had elaborated various forms of the doctrine called moderate realism, according to which there are common natures in individual existing things, distinct from their individuating principles although not separable except in thought. On the psychological side, these doctrines held that the human intellect abstracts, from the particular presentations of sense experience, an intelligible species, or likeness, by means of which it apprehends the common nature apart from the individuating conditions. The varieties of this moderate realism turned on the answer to the question of whether, in an individual, the common 414
William of Ockham nature is (1) really distinct from the individuating principle or (2) "formally distinct," as Duns Scotus proposed or (3) distinct only according to the mode of consideration although involving some "foundation in the thing" for such distinguishability, as Aquinas held. Ockham considered all forms of this doctrine of common natures in individual things to be self-contradictory and irrational. If the human nature of Socrates is really distinct from Socrates, then it is not Socrates' nature or essence, for a thing cannot be said to be essentially something that it really is not. If the common nature is anything at all, it is either one thing or many things; if one and not many, it is not common but singular, and if not one but many, then each of the many is singular and there is still nothing common. The answer of Duns Scotus—that the common nature is really identical with, but formally distinct from, the haecceitas or individuating differentia that was said to contract the specific nature to singularity—was an attempt to find something intermediate between identity and nonidentity. Ockham argued, against the Scotist thesis, that if the specific nature and the individuating difference are really identical, they cannot be formally distinct; and if they are formally distinct, they cannot be really identical. Scotus had claimed that they are both really identical and formally distinct. Let a and b represent the individual difference and the specific nature, respectively. Then, since a is not formally distinct from a, it follows that if a is identical with b, then b is not formally distinct from a. Similarly, since a is not formally distinct from a, then if b is formally distinct from a, b is not identical with a. In these arguments Ockham employs, with great effectiveness, the principle commonly ascribed to Leibniz—that if two things are identical, whatever is true of one is true of the other; and if something is true of one that is not true of the other, they are not identical. The third answer—that the same thing is singular and universal according to different ways of considering it—is ridiculed by Ockham on the ground that what a thing is in itself can in no way depend on how someone thinks of it. "For with the same ease I could say that a man considered in one way is an ass, considered in another way he is an ox, and considered in a third way he is a she goat" (Expositio Super VIII Libros Physicorum, in Philotheus Boehner, ed., Ockham: Philosophical Writings, p. 14). Nor can it be said, as Aquinas appears to say in his De Ente et Essentia, that the nature or essence of a thing is in 415
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itself neither individual nor universal but is made singular by being received in individuating matter and is made universal by being received into the mind. Anything whatsoever, Ockham insists, is one thing and a singular thing by the very fact that it is a thing, and it is impossible that its unity or singularity is due to something added to it. It remains, then, that universality and community are properties only of signs—of language expressions and of the acts of thought expressed by them. The problem of universals therefore is not a metaphysical problem of explaining how abstract common natures are individuated to singular existence, nor is it a psychological problem of explaining how the intellect can abstract from the images of sense experience a common nature inherent in the individuals experienced; for there are no common natures to be individuated or to be abstracted. The problem of individuation is a logical problem of showing how general terms are used in propositions to refer to individuals signified by them; this problem is resolved in terms of the quantifying prefixes and other syncategorematic determinants of the referential use of terms in propositions. As an epistemological problem, the problem of universals is that of explaining how experience of individual existing things can give rise to concepts of universal character and to universally quantified propositions that hold for all objects signified by the subject term. The basis of Ockham's answer to these problems is given in his doctrine of intuitive and abstractive cognition. The doctrine of intuitive and abstractive cognition is formulated at the beginning of Ockham's Commentary on the Sentences in connection with the question of whether evident knowledge of theological truths can be acquired by man in this life. After distinguishing apprehension from judgment as a distinct act of the intellect, and after showing that every act of judgment presupposes an act of apprehension of what is signified by the terms of the proposition expressing such a judgment, Ockham distinguishes two kinds of intellectual apprehension, intuitive cognition and abstractive cognition. Intuitive cognition is defined as an act of apprehension in virtue of which the intellect can evidently judge that the apprehended object exists or does not exist, or that it has or does not have some particular quality or other contingent condition; in short, an intuitive cognition is an act of immediate awareness in virtue of which an evident judgment of contingent fact can be made. 416
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Abstractive cognition is defined as any act of cognition in virtue of which it cannot be evidently known whether the apprehended object exists or does not exist, and in virtue of which an evident contingent judgment cannot be made. That these two ways of apprehending the same objects are possible is clear from experience; while I am observing Socrates sitting down, I can evidently judge that Socrates is seated, but if I leave the room and then form the judgment that Socrates is seated, it is not evident, and may indeed be false. The important point in this distinction is that intuitive and abstractive cognition do not differ in the objects apprehended, but solely in the fact that intuitive cognition suffices for making an evident contingent judgment concerning the object apprehended, whereas an abstractive cognition does not. Nor is the distinction one between sensation and thought, for however much it may be true that affection of the senses by the external object is a necessary condition for an intuitive cognition of a sensible object, the intuitive cognition is an intellectual act that is presupposed by the act of judgment whose evidence is derived from it. Neither is the distinction one between direct awareness of the object and awareness of something representing the object in its absence; both kinds of apprehension are directly of the object. It is not even logically necessary that the object of an intuitive cognition be present or actually existent, although if, by the power of God, an intuitive cognition of an object were preserved after the object was removed or destroyed, it would then yield the evident judgment that the object was not present or that it did not exist; for it is self-contradictory, and hence not even within the power of God, for a cognition to yield an evident judgment that an object exists if the object does not exist. Ockham must admit that an intuitive cognition of a nonexistent object is logically possible because an intuitive cognition, however much it may be caused by the presence of its object, is not identical with its object; hence it is not self-contradictory that it exists without the object's existing. And if we suppose that any effect that can be produced by a created cause can be produced by God without the created cause, this logical possibility could be realized by the power of God. In this way God could, and according to Christian belief did, produce intuitive cognitions of future things and events by which the prophets and saints had evident knowledge of what did not yet exist; and God himself, who apprehends all things intuitively and not 411
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abstractively, is aware not only of the things he has created but of all the things he does not choose to create. Thus, an intuitive cognition of a nonexistent object is logically possible, although it is realizable only by the power of God. Without such divine intervention, however, such cognitions can arise only if the object is present to the knower; and the judgments to which intuitive cognitions can give rise, in the natural course of events, are affirmative judgments of present existence and present fact. Ockham does not restrict the objects of intuitive cognition to objects perceptible to the external senses but includes nonsensible actualities that are apprehended introspectively, such as thoughts, volitions and emotions. Thus the intellect, by reflecting on its own acts, can form evident judgments of the existence of those acts; for example, if I am intuitively aware of Socrates being seated, I can not only judge evidently that Socrates is seated, but I can also give evident assent to the second-order proposition "I evidently know that Socrates is seated." Although Ockham generally holds that the reflexive act is distinct from, and posterior to, the direct act, he speaks as if the evidence of the reflexive act can include that of the direct act. Given an intuitive cognition of some object or event, the intellect thereby acquires an abstractive cognition of the same object or event, which it retains as a habitus, or acquired capacity, to conceive the object without any causal concurrence by the object itself; thus, objects that we have experienced intuitively can be apprehended abstractively, the only difference being that the abstractive cognition does not suffice to make evident a contingent judgment concerning the object thought of. If we leave out of account the logically possible case of God's producing an abstractive cognition without a preceding intuitive cognition, the principle holds, according to Ockham, that no abstractive cognition can be had that is not derived from an intuitive cognition of the object or objects conceived. This principle, which corresponds to Hume's thesis that there is no idea which is not derived from one or more impressions, is basic to Ockham's theory of natural knowledge and its source of evidence. In his earlier formulation of the doctrine of intuitive and abstractive cognition, Ockham supposed that the abstractive cognition immediately derived from an intuitive cognition is a concept only of the singular object of the intuitive cognition. But in his Quodlibeta (Quod. I, q. 13) he states that a simple abstractive cognition cannot be a 418
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concept peculiar to one singular object to the exclusion of other objects that would, if apprehended intuitively, yield a wholly similar concept. Thus the universality of the concept, in this later theory, is immediately involved in the transition from intuitive to abstractive cognition. The operation is analogous to that of deriving, from a proposition of the form Fa, the open sentence Fx, which becomes a general proposition when the free variable x is bound by a quantifying prefix. In Ockham's terminology, the abstractive cognition has signification but acquires supposition only by formulation of a judgment or proposition. The concept, or universal in the mind, is a cognition of objects in virtue of which it cannot be evidently judged that they exist or do not exist. But what sort of reality is such a cognition or concept? One opinion is that the concept is a mental image or species which, because it is a resemblance of the external objects, causes the intellect to become aware of those objects. But Ockham points out, as Hume did later, that such a species could in no way represent to the intellect the objects of which it is a likeness, unless these objects were already known to it—no more, Ockham says, than a statue of Hercules could represent Hercules, or be recognized as his likeness, if the viewer had never seen Hercules. In his Commentary on the Sentences Ockham mentions three theories of the concept as "probable" or tenable. According to the first theory, the concept is not a reality existing in the mind or outside the mind but is the being conceived of the external objects, the esse obiectivum of the objects—a view that was held by Peter Aureol and had adherents down to the time of Descartes, who in the Meditations used this notion of the "objective being" of the concept in proving God's existence from his idea of God. Of the concept thus conceived, Ockham says that its being is its being understood—eorum esse est eorum cognosci. A second theory supposes that the concept is a real quality in the soul, used by the intellect for the individuals of which it is a concept, just as a general term in a proposition is used for the individuals of which it is a sign. A third theory, which Ockham finally adopted, is that the concept is merely the act of understanding the individual things of which it is said to be a concept. This theory is preferred on grounds of economy, for inasmuch as any of the theories requires that the intellect apprehend the extramental individuals, this function can be satisfied by the act of understanding without 419
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need of any other mental vehicle serving as surrogate for the objects. The question may well be raised of how a concept derived from intuitive apprehension of a single object can constitute an act of understanding a definite set of objects—not any objects whatsoever but just those objects to which the concept is applicable or which, if directly experienced, would elicit that concept. Why should an intuitive cognition of Socrates yield a general concept applicable to just those individuals of which it is true to say "This is a man"? Ockham says that this is because the objects are similar, on which account the abstractive concept elicited by experience of one of the objects is ipso facto a concept of all similar objects. The realist might well insist that Ockham, in supposing this similarity in things, is covertly reintroducing the doctrine of common natures; but Ockham replies that similar individuals are similar by reason of what each individual is in itself, and not by reason of anything common. Two things are similar, for example, in being singular things, but this is not because there is one singularity common to the two things. Thus a concept can be a single act of understanding many individuals that are similar, without being an act of understanding anything other than just those individuals themselves. Again the analogy with the open sentence Fx is suggested, for if we should ask what things satisfy this function, the answer is that it is any of those things such that Fx holds for it. The obvious circularity of this question and answer indicates that any explanation that can be given of the fact that things are conceived in a universal manner by intelligent beings must itself use such universal concepts and thereby must presuppose the fact to be explained. In this account Ockham describes concepts as natural signs whose relation to the things conceived is established not by human choice but by the fact that an act of understanding has no content other than the objects understood and arises in the first instance only through direct experience of such objects. Ockham seems to recognize the futility of seeking to account for the possibility of knowledge as such by means of a particular branch of knowledge like physics or psychology; "natura occulte operatur in universalibus [nature works in a hidden manner in the case of universals]," he remarks, and is content to leave it at that. Although the human intellect, according to Ockham, can directly apprehend and conceive the individual things that exist independently of our thought, the objects of knowledge (in the sense of scire) are 420
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propositions, formed within our minds by operations we freely perform b y combining concepts derived from intuitive cognitions of things. Only propositions can be true or false, and since knowledge is of the true, its objects are propositions—complexes of signs put together by us. Logic is concerned with these ways of putting concepts together, insofar as these operations affect the truth or falsity of the resultant propositions. Ockham was skilled in the formal logic developed in the arts faculties of the universities on foundations laid in the twelfth century by Peter Abelard, and represented in the thirteenth century b y the treatises of the so-called terminist logicians William of Sherwood and Peter of Spain. T h e distinctive feature of this logic was its use of the concept of the supposition of terms in formulating the syntactical and semantical properties of cognitive language. In his Summa Logicae Ockham systematized the contributions of his predecessors in a reformulation of the whole content of Aristotelian logic on semantical foundations of a purely extensional character. These foundations, exhibited in his analysis of the signification of terms and of the truth conditions of propositions, reveal the ontological basis of his empiricist theory of knowledge and of scientific evidence. Some preliminary distinctions made at the beginning of Ockham's work on logic are important for understanding this analysis. Logic, as a scientia sermocinalis, or science of language, deals with language as a system of signs that can be used in making true or false statements about things signified by those signs. T h e expressions of spoken and written language are instituted by convention to signify what is naturally signified (or intended) b y acts of thought constituting the "inner discourse of the soul." Logic studies the properties of language expressions insofar as they embody the logically essential functions of mental discourse. Medieval logicians distinguished language signs into t w o basically different types: categorematic signs, which have independent meaning and can function as subjects and predicates of propositions, and syncategorematic signs, which have no independent meaning but exercise various logical functions with respect to the categorematic signs. This important distinction corresponds to that made in modern logic between descriptive signs and logical signs. T h e categorematic signs, normally called terms, were divided into two distinct and nonoverlapping semantical types: terms of first intention, which signify things that are not language 421
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supposition. The concrete terms of the so-called categories of accident, which are predicable of substance terms but signify them only as "of such quality," as "so big," or as "in such a place," were called by Ockham connotative terms—terms that refer obliquely to something other than the thing or things for which they can stand, and imply some contingent factual condition determining the range of objects for which the term can stand. The oblique reference may be to a part or parts of the object directly denotable by the term, to a quality of the object, or to some other thing or things with respect to which the denoted thing stands in some contingent relation—for instance, the term "father" stands for one thing by referring to another thing (a child) and implying that the child was generated by the person who is directly designated by the term "father." Ockham's nominalism consists in his refusal to construe abstract terms as names of entities distinct from the individual things signified by absolute terms. The realists, while conceding that the concrete forms of connotative terms stand for substances, held that their oblique reference is to entities distinct from these substances but inhering in them—these distinct entities being directly named by the abstract forms of such connotative terms. Thus the term "father," in their view, connotes an entity called fatherhood and implies that it inheres in the thing denoted by the term "father." Similarly the term "large," although predicable of terms signifying substances, was said to connote an entity, distinct from such substances but inhering in them, called quantity or magnitude. Ockham was willing to grant that terms signifying sensible qualities, such as "white," "hot," and "sweet," connote entities that are distinct from substances and are directly signified by the abstract terms "whiteness," "heat," and "sweetness"; hence he admitted as absolute terms the abstract forms of those qualitative predicates. But in all other cases he held that connotative terms, whether concrete or abstract, signify no entities other than those directly signifiable by substance terms or by these absolute quality terms. What the realists had done, in Okham's view, was to treat facts about substances as entities distinct from those things, as if the fact that a man is six feet tall is an entity distinct from the man but inhering in him, or as if the fact that Socrates has fathered a son is an entity distinct from Socrates and from his son. From a logical point of view, Ockham's analysis is a restriction of the domain of reference of terms, or of the domain of objects con423
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stituting possible values of the variable of quantification, to individual substances and singular (not common) sensible qualities. Ontologically, this means that the only things that there are, are individual substances and equally individual qualities. All terms that are not direct names (or absolute signs) of these objects are predicate terms which, although referring to no other objects than these, do so by indicating a contingent fact about such objects. In thus impoverishing the domain of objects of reference, Ockham enriches the domain of truths to be known about these objects. The frequent charge that Ockham atomized the world by refusing to recognize relations as real entities distinct from substances and qualities fails to take account of the fact that the connotative terms relate the individuals by implying factual conditions by which the objects are tied together in an existential sense—something that cannot be done by treating relations as entities distinct from their relata and, in effect, as just another class of substances. From Ockham's point of view, it was the realists who atomized the world by treating all predicates as absolute names. In rejecting the thesis that predicates designate entities distinct from the individuals denoted by absolute terms, Ockham rejects the interpretation of the affirmative copula as a sign of the inherence of an abstract entity in the individuals denoted by the subject term. The truth condition of an affirmative categorical proposition, in Ockham's interpretation, is that subject and predicate "stand for the same." Thus, in the proposition "Socrates is an animal," it is not indicated that Socrates has animality or that animality inheres in Socrates, but it is indicated that the individual denoted by the name "Socrates" is an individual for which the term "animal" stands and which it signifies. In universally quantified propositions, the affirmative copula indicates that every individual for which the subject term stands is something for which the predicate term stands; and in particular, or existentially quantified, propositions, the affirmative copula indicates that there is at least one individual signified by the subject term that is also signified by the predicate term. This analysis of general propositions corresponds closely to the modern formulas (x)Fx => Gx and ( x) Fx' Gx, except that the medieval analysis requires existential import as part of the truth condition of the universal affirmative and does not require existential import as a truth condition of the particular negative. In order for subject and 424
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predicate to stand for the same, there must be something they stand for; but it is not required that they stand for something in order that they not stand for the same thing. Ockham skillfully carried out the formal development of truth rules for propositions of more complex forms and for various modalities and used them in formulating inference rules both for syllogistic arguments and for arguments based on truth-functional relations between unanalyzed propositions. The Aristotelian dictum that science is of the universal was accepted by Ockham in the sense that scientific knowledge is of propositions composed of universal terms, quantified universally for all the individuals signified by the subject term and having the properties of necessity and evidence. Strictly speaking, scientific knowledge is only of demonstrable conclusions evident by reason of indemonstrable, necessary, and evident premises from which they are logically deducible. But Ockham extends the notion of scientia, defined as evident grasp of a proposition that is true, to include the indemonstrable premises of demonstrations and also to include evident knowledge of contingent propositions in virtue of intuitive cognition. Since, for Ockham, the universal propositions of scientific demonstrations are formed only from concepts by which things are apprehended abstractively and without evidence of their existence, the question of what kind of evidence such propositions can have is a crucial question for him. This problem reduces to that of the evidence of the indemonstrable premises of the sciences. Aristotle's characterization of such premises as necessary, self-evident (per se nota), and primary could not be accepted by Ockham without considerable qualification. First of all, he says that no such propositions are necessary as assertoric categorical propositions, but are necessary only if they are construed as conditionals or as propositions concerning the possible (de eo quod potest esse). Second, he distinguishes between two kinds of evidence that such propositions, construed as conditionals or as of the mode of possibility, may have: the proposition may be evident by the meaning of its terms (per se nota) or evident by experience (nota per experientiam). The first kind of evidence is obtained through the premises of mathematical demonstrations and by those premises of the natural sciences which are analytically evident by the definition of the terms. But in every natural or physical science there are premises that are not per se nota but are established by generalization from singular contingent propositions evident by 425
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intuitive cognition; such are the premises that state causal laws or correlate dispositional properties with their commensurately universal subject terms. What justifies the passage from singular propositions evident by direct experience to universal propositions affirmed for all possible cases? How does evident knowledge that this particular wood is combustible, acquired by direct observation of its burning, allow us to know that any piece of wood, if subjected to fire in the presence of air, will burn? Ockham invokes as justification for such generalized propositions a rule of induction, described as a medium extrinsecwnt, that corresponds to the principle of the uniformity of nature—that all individuals of specifically similar nature (eiusdem rationis) act or react in similar manner to similar conditions. He regards this principle as analytically evident from the meaning of "similar nature"; but since it is logically possible, and hence possible by the power of God, that an effect can be produced without its natural cause, the application of this rule of induction in establishing general premises or laws on the basis of experience of particular cases is valid only within the general hypothesis of the common course of nature (ex suppositione communis cursus naturae). Consequently, the evidence of such premises of the natural or positive sciences is not absolute but hypothetical. It should be further noted that Ockham, and his contemporaries as well, drew a sharp distinction between what comes to be by nature and what comes to be by the action of voluntary intelligent agents, both man and God. The principle that like causes produce like effects under like conditions is considered valid only on the supposition that no voluntary agencies are involved. There is a marked analogy between Ockham's view of the evidential status of the premises of the empirical sciences and that of the premises of positive (or revealed) theology. In the one case their evidence is conditional on the hypothesis of a common course of nature, and in the other on the hypothesis of a revealed order of grace freely (and hence not necessarily) provided by God for the salvation of human souls. Neither hypothesis is logically or metaphysically necessary, and each is, in its own domain, used as a methodological principle pragmatically justified by its fruitfulness. What corresponds to Pelagianism in theology is dogmatic Aristotelianism in natural philosophy, and Ockham takes due precautions against both. Ockham's metaphysics is primarily a critique of the traditional 426
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metaphysical doctrines of his scholastic predecessors. Most of these doctrines represent, in Ockham's view, confusions of logical and physical concepts or of ways of signifying things and the things signified. Such is the case with the supposed distinction, in things, between their essence and their existence, and with the distinction between potential and actual being; to say that something exists does not mean that there is something which is of itself nonexistent to which existence is added, and to say that something exists potentially does not mean that "something which is not in the universe, but can exist in the universe, is truly a being" (Summa Logicae Pars Prima, 1951, p. 99, 11. 55-58). These are distinctions between two modalities of statements, assertoric, and de possibili, and not between things denoted by the terms of statements. The old issue of whether "being" is predicated univocally, equivocally, or analogically of substances and accidents, and of God and creatures, is resolved by saying that in the sense in which "being" is equivalent to "something," it is predicated in the same way of everything there is; but if "univocal" is taken as meaning that the term signifies everything according to a single determinate concept, the term "being" is equivocal and has as many meanings as there are kinds of things. The first sense is like saying (x) (x=x); the second, or equivocal use, is indicated if we say "to be a man is not to be white." The term "substance," for Ockham, has the sense of Aristotle's primary substance, or faroKeifievov, rather than the sense of intelligible essence, or TO RI fy elvai. Basically, substance is conceived as the individual subject or substratum of qualities, and with regard to corporeal substances Ockham indicates that we are aware of substances only as the subject of sensible qualities. Thus he says that "no external corporeal substance can be naturally apprehended in itself, by us, however it may be with respect to the intellect itself or any substance which is of the essence of the knower" (Commentary on the Sentences I, d. 3, q. 2), and he adds that "substance is therefore understood in connotative and negative concepts, such as 'being which subsists by itself,' 'being which is not in something else,' 'being which is a subject of all accidents,' etc." (ibid.). These remarks suggest that the general terms of the category of substance are not as absolute as Ockham elsewhere supposes, and that the only nonconnotative concept is the transcendental concept "being" or "thing"; on this basis, general names are eliminated in favor of connotative predicates, 421
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proper names are eliminated in favor of descriptive phrases, and the whole category of substance is reduced to the referential function expressed in language by the phrase "thing such t h a t . . . , " or by what is equivalent to the bound variable of quantification. Historically, Ockham's conception of substance as the posited (or "supposited") referent of the connotative predicates points toward Locke's "something I know not what" characterization of substance; similarly, Ockham's treatment of sensible qualities as entities distinct from substances (and by the power of God separable, as in the Sacrament of the Altar), along with his contention that quantitative predicates signify nothing other than substances having parts outside of parts, pointed the way to the seventeenth-century treatment of qualities as secondary and quantitative attributes as primary. With respect to the notion of cause, Ockham effected a considerable modification of the traditional Aristotelian doctrine. The intrinsic causes, matter and form, were construed physically rather than metaphysically; matter is not, for Ockham, a pure potentiality but is actual in its own right as body having spatially distinguishable parts, its extension being, in the scholastic terminology, the form of corporeity. The concept of form likewise is understood physically in the sense of fju>pr} rather than of etSo?, and tends to be understood as shape and structure of the material parts. This is shown in Ockham's rejection of the notion of a form of the whole ( f o r m a totius) and in his thesis that a whole is its parts. Many pages of Ockham's works are devoted to the thesis, defended with an almost ferocious intensity, that quantity is not any entity other than substance (or quality), but is substance or sensible qualities as divisible into parts, or as numerable. This doctrine clearly suggests the later view that the primary qualities signified by quantity terms constitute the real essence of substances. The tendency toward a more mechanistic theory of natural substances and events is evident in Ockham's treatment of efficient causality. He says that one thing is said to be cause of another if, when it is present, the effect follows, and when it is not present, the effect does not occur. Such a causal relation can be known only by experience, and it is impossible to deduce a priori, from knowledge of one thing, that something else must result from it. This is so on the general epistemological principle that from the cognition of one thing we cannot acquire "first knowledge" of another thing which is really distinct from it but must have intuitive cognition of the latter in itself. 428
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Hence the knowledge that one thing is the cause of another, or that something is caused by some other definite thing, is acquired only if we have intuitive cognition of each of the two things and repeated experience of their concomitance or sequence. Like Hume, Ockham bases our knowledge of causal relations on experience alone and rejects the doctrine that the effect is virtually in its cause and deducible from the essential nature of the cause. But he is not skeptical with regard to the objectivity of causation; his point is that the only evidence we have of causal connections is experience of observed sequences. Although we cannot establish the causal relations between things a priori, and must accept the principle of the uniformity of nature as an act of faith, Ockham's faith in this principle appears to be as firm as his faith in the revealed doctrines of theology. In his Summulae Physicorum (II, c. 12) he says: "Leaving out of consideration all free and voluntary agencies, whatever happens by [natural] causes occurs of necessity and inevitably, and nothing of that sort occurs by chance" (1637 ed., p. 14). The Aristotelian doctrine that nature acts for an end is interpreted by Ockham as a pure metaphor. In his Quodlibeta (Quod. IV, qq. 1 and 2) he states that it cannot be shown by any self-evident premises or by experience that any effect whatsoever has afinalcause, whether distinct from the agent or not distinct from the agent; for that which acts by necessity of nature acts uniformly under like conditions, and it cannot be shown that it does so because of some end desired or aimed at. We speak of natural processes as having ends, not because the agents are really "moved by desire" but sfmply because natural bodies under similar conditions are observed to act in determinate ways, as if aiming at an end. But such language is purely metaphorical. In applying his strict criteria of evidence to the doctrines of Aristotelian physics and cosmology, Ockham shows that many principles which Aristotle took to be necessary and self-evident are not. The arguments that celestial bodies have no matter and are ingenerable and incorruptible, that there cannot be a plurality of worlds, and that action at a distance is impossible were held by Ockham to be inconclusive and nonevident. Although Ockham was not concerned with establishing a new physics and cosmology to replace that of Aristotle, his critical treatment of Aristotle's arguments and his constant insistence on the possibility of different theories equally capable of accounting for the facts to be explained were influential in creating the 429
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intellectual environment in which later fourteenth-century philosophers explored new physical theories and laid some of the foundations for the scientific revolution of the seventeenth century. As a theologian, Ockham was concerned with the question of the cognitive status of theology. The thirteenth-century Scholastics had, for the most part, characterized theology as a science, on the ground that it contains truths which are necessary and "in themselves" evident, even though most of them are not evident to man in his present condition. The question of how we can know that a proposition is evident-in-itself, when it is not evident to us, was answered by saying that a person who does not know geometry may yet be fully assured that a theorem which is an object of belief to him is an object of scientific knowledge to the expert mathematician. Thus, Aquinas said that the articles of faith from which the theologian demonstrates his conclusions are accepted as evident in the light of a higher science (that of God), much as the astronomer accepts the theorems of geometry as premises for his astronomical reasonings but nevertheless demonstrates the conclusions of astronomy in a scientific manner. Ockham, in a question of his Commentary on the Sentences (Prologue, q. 7), examines this and other similar arguments and rejects them as invalid. Every truth evidently known, he says, is either selfevident (per se nota), deduced from such, or is evident from intuitive cognition; but the articles of faith are not evidently knowable by man in any of these ways in his present life, for if they were, they would be evident to infidels and pagans, who are not less intelligent than Christians. But this is not the case. Furthermore, it cannot be maintained that theology is a science because it carries out valid processes of deduction of conclusions from the premises accepted on faith, for conclusions cannot be any more evident than the premises from which they are derived. Ockham subjects the prolegomena fidei, or propositions about God held to be evidently knowable on natural grounds, to the criteria of evidence and proof that pertain to the natural or philosophical sciences. The issue of whether there is a natural theology as a part of philosophy reduces to the question of whether, from analytic premises evident from the meaning of the terms or from empirical evidence provided by direct experience of the object of theology, such a science is possible. It is conceded by all that man, in his present life, does not have intuitive cognition of God—not, certainly, by getting a 430
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degree in theology. But Ockham had argued, with respect to any naturally acquired knowledge, that it is only b y intuitive cognition of an object that we can evidently judge that it exists—and the only objects of which we can have simple abstractive concepts are those w e have experienced intuitively or those specifically similar to them. From this it follows that we cannot have any simple and proper concept of God nor any direct evidence of his existence. Can we, then, from concepts derived from experience of other things, form a complex concept or description uniquely applicable to God and prove that an object satisfying this nominal definition exists? Ockham admits that a descriptive concept of G o d can be formed from the concept of "being" or "thing" in its univocal (but empty) sense, along with such connotative or negative terms as "nonfinite," "uncaused," and "most perfect." But proving that there exists an object so describable is another matter. T h e arguments b y which his predecessors had attempted to prove God's existence are examined b y Ockham with great thoroughness in his Commentary on the Sentences, in the Quodlibeta, and in the possibly inauthentic Centiloquium Theologicum. St. Anselm's so-called Ontological Argument is analyzed (and shown to consist of two different arguments) but is rejected as invalid; and the old arguments from degrees of perfection are disposed of without difficulty. It is chiefly the causal arguments, in the form used b y Duns Scotus, that Ockham takes seriously; and these he examines with extraordinary care because of the w a y in which Scotus used the concept of infinity in formulating them. Ockham's great logical skill is revealed at its best in his patient and remorseless untangling of the subtleties of the Scotist arguments. Those involving final causality are shown to have no force in themselves, so that the main issues are faced in the arguments from efficient causes. T h e thesis that there cannot be an infinite regress in the order of efficient causes is rejected as nonevident if the causes are successive in a temporal sense, but Ockham is willing to grant that there cannot be an infinite regress of "conserving causes," since these would have to exist simultaneously. Ockham does, therefore, allow that the existence of at least one conserving cause can be proved if it is granted that there are things whose existence is dependent on conservation b y something else; but he immediately points out that w e could not prove that there is only one such conserving cause, nor could w e prove that the celestial spheres are not sufficient 431
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to account for the conservation of the things in the world. Thus the value of this argument for theological purposes is very slight indeed. It is also clear that a natural theology, in the sense involving strictly scientific or evident demonstrations, is completely ruled out by Ockham's basic epistemological principles. He is willing to concede that it is "probable" that there is one supreme being, that this being is the cause of at least part of the movements and order of the world, and that this being is of an intellectual nature; but since Ockham defines "probable," following Aristotle's Topics, as an argument or premise that appears to be true to everyone, to the majority, or to the wisest, all this means is that most people, and the philosophers of old, have believed that there is a deity of this sort. To conclude, from Ockham's merciless criticism of alleged proofs of theological beliefs, that he was an unbeliever and a religious skeptic would be a mistake—although some have drawn this conclusion. There is much evidence in Ockham's writings of an intense loyalty to the Christian faith and of full commitment to the articles of faith as divinely revealed. What Ockham appears to have found objectionable in the theological work of his contemporaries was their attempt to prove what cannot be proved and their loading of theology with pseudo explanations that merely blunted and obscured the tremendous implications of the fundamental articles of the Christian faith. The omnipotence of God and his absolute freedom are the two articles of Christian belief that Ockham never loses sight of; and in his internal treatment of the content of Christian doctrine, just as in his internal treatment of natural philosophy, Ockham invokes these articles of faith as justification for an empiricist or positivistic position. Just as the hypothesis of the common course of nature is a methodological postulate of physical explanation, so the order of grace as set up in the sacramental system and laws of the church is accepted as a postulate of the Christian life; but just as God is not bound or obligated by the order of nature he has established, so he is not bound or obligated by the order of grace he has established as the "common way" of salvation of souls. Neither order is necessary in itself or a necessary consequence of God's being or essence; the utter contingency of the created world, whose existence and order is a sheer fact without any metaphysical ground of necessity, is for Ockham a consequence of the omnipotence and absolute freedom of God that cannot, and should not, be softened or obscured 432
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by attempts to construe it in terms of the metaphysics of pagans and infidels. In contrast with most of the thirteenth-century scholastic doctors, Ockham made little attempt to formulate a rational psychology or theory of the human soul. In his Quodlibeta (Quod. I, q. 10) he raises the question of whether it can be demonstrated that the intellective soul is a form of the body. Since the Council of Vienne had ruled a few years before that this Thomist doctrine was de fide (although the formulation was ambiguous enough to allow some latitude), Ockham was not as critical of it as he might otherwise have been. He points out that a person following natural reason would no doubt suppose that his own acts of understanding and of will, of which he has intuitive cognition, are acts of his substantial being or form; however, he would not suppose this to be an incorruptible form separable from his body but rather an extended and corruptible form like that of any other material body. If, however, we must understand by "intellective soul" an immaterial and incorruptible form that exists as a whole in the whole body and as a whole in each part, "it cannot be evidently known by reason or experience that such a form exists in us, nor that the understanding proper to such a substance exists in us, nor that such a soul is a form of the body. Whatever the Philosopher thought of this does not now concern me, because it seems that he remains doubtful about it whenever he speaks of it. These three things are only matters of belief" (ibid.). Ockham thought that the Franciscan doctrine of a plurality of forms in the human being is more probable on natural grounds than the doctrine of a single form; indeed, if matter has its own corporeal form (forma corporeitatis) as extended substance, the sensitive soul would be a distinct form of organization of this matter; and the intellectual soul, if immortal and incorruptible, might well be in the organic body as a pilot is in his boat. But the only evident knowledge we have of ourselves as minds is the intuitive cognition of our acts of thinking and willing, and the subject of these acts is not apprehended directly as a substance or form. Nor is the faculty psychology elaborated by the earlier Scholastics, with its distinctions of active and passive intellect and of really distinct powers within the soul, evident or necessary. We are aware of the soul only as that which thinks and wills; and since the person who thinks is not other than the person who wills, the terms "intellect" and "will" refer to precisely the same 433
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subject, and not to distinct entities or faculties within that subject. If it is only by intuitive cognition of our own acts that we are aware of ourselves as intelligent beings, it is only in this way that we are aware of ourselves as voluntary agents free to choose between opposite actions. Ockham defines freedom (libertas) as "that power whereby I can do diverse things indifferently and contingently, such that I can cause, or not cause, the same effect, when all conditions other than this power are the same" (Quod. I, q. 16). That the will is free, he says, cannot be demonstratively proved by any reason, "because every reason proving this assumes something equally unknown as is the conclusion, or less known." Yet this freedom can be evidently known by experience, he says, because "a man experiences the fact that however much his reason dictates some action, his will can will, or not will, this act" (ibid.). This liberty of will, for Ockham, is the basis of human dignity and of moral goodness and responsibility, more than the power of thinking—although the two are mutually involved. The seat of morality is in the will itself, Ockham says, "because every act other than the act of will, which is in the power of the will, is only good in such manner that it can be a bad act, because it can be done for an evil end and from an evil intention" (Quod. Ill, q. 13). Also, every action, other than the act of willing itself, can be performed by reason of natural causes and not freely, and every such action could be caused in us by God alone instead of by our will; consequently, the action in itself is neither virtuous nor vicious, except by denomination from the act of the will. Not even Kant was more concerned to distinguish morality from legality, or the good will from the right action. Ockham had, in Peter Abelard, a medieval precedent for this emphasis. Having thus affirmed the total freedom and integrity of the human will, Ockham was faced with the problem of reconciling this with the doctrine of divine foreknowledge of future contingent events, among which the decisions of the human will must be counted. The answer, apparently considered sufficient by Aquinas, that God sees, in one eternal glance, all the decisions of each soul, now and to come, is not sufficient for Ockham. God's intellect is not distinct from his will and his omnipotent causality of all things; hence, says Ockham, "either the determination or production of the created will follows the determination [of the divine will], or it does not. If it does, then the created will acts just as naturally as any natural cause . . . and thus, 434
William of Ockham the divine will being determined, the created will acts accordingly and does not have the power of not acting accordingly, and consequently no act of the created will is to be imputed to it" (Commentary on the Sentences, d. 38, q. 1). Ockham considers the problem of how God knows, with certainty and from all eternity, the contingent and free decisions of the human will, an insoluble problem; for both the freedom of the human will and the power of God to know all contingent acts of created beings must be conceded. "It is impossible," he says, "for any [created] intellect, in this life, to explain or evidently know how God knows all future contingent events" (ibid.). While recognizing the Aristotelian conception of natural good and of virtuous choices in accordance with right reason, Ockham is primarily concerned with the theological norm of moral goodness, which is the will of God expressed in the commandments of both the Old Testament and the New Testament, whereby man is obligated (but not coerced) to love and obey God above all else. Thus, what God wills man to do of man's free will defines the right, and disobedience to God's will defines sin. This provides a solution of the old problem of evil, or of God as cause of the sinful acts of man; for since moral evil is the doing of the opposite of what one is obligated to do, and since God is not obligated to any act, it is impossible for God to sin by his causal concurrence in the production of an act sinfully willed by the creature. But Ockham raises an interesting paradox in this connection by supposing that God might command a man to hate him (or to disobey him). To obey God is to love God, and to love God is to do his will; but if it is God's will that I do not do his will, I do his will if I don't, and don't do it if I do. Hence, this command is impossible for a creature to fulfill; and although there would seem to be no patent self-contradiction in supposing that God could issue such a command, it would seem to be self-contradictory, and hence impossible, for God to will that this command be fulfilled. Although Ockham recognizes that God has established laws binding the Christian to live in a certain way as a member of the church, participant in its sacraments, and believer in its articles of faith, this fact imposes no obligation on God either to bestow eternal life on the Christian who obeys God's precepts and loves him above all else, or to withhold eternal life from those who do not follow God's laws and love him above all else. "It is not impossible," Ockham says, "that God could ordain that a person who lives according to right reason, 435
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and does not believe anything except what is conclusive to him by natural reason, should be worthy of eternal life" (Commentary on the Sentences III, q. 8). Similarly, although according to the established order an infused grace is required for a man to be eligible for acceptance by God, Ockham insists that God is not necessitated, by reason of such a created grace given to a man, to confer eternal life on him—"always contingently and freely and mercifully and of his own graciousness he beatifies whomsoever he chooses . . . purely from his kindness he will freely give eternal life to whomsoever he will give it" (Commentary on the Sentences I, d. 17, q. 1). What is distinctive of Ockham's theological point of view is its emphasis on the freedom and spontaneous liberality of God and on the "givenness" of the world that God creates. This stands in sharp contrast to the Muslim characterization of God as the necessary being whose act is equally necessary and therefore determinant of necessity in all that occurs in the created world. Ockham's doctrine of divine omnipotence is not to be understood, as some have done, on the analogy of an oriental potentate issuing arbitrary commands as a pure display of power; rather, it is grounded in the conception of a goodness that is purely spontaneous and unnecessitated, whose gift of existence to creatures and of freedom of choice to man is a perfectly free gift with no strings attached. Ockham's theology of divine liberty and liberality is the complement of his philosophy of radical contingency in the world of existing finite beings and of the underivability of matters of fact from any a priori necessity. Ockham's political and polemical writings on the issue of papal power eloquently convey the thesis that the law of God is the law of liberty and not one of oppression or coercion. The treatise De lmperatorum et Pontifictmt Potestate ("On the Power of Emperors and Popes"), dealing with the papal claim to plenitude of power, makes this very clear. Christ, in instituting the church, did not give Peter a plenitude of power that would give him the right to do everything not explicitly forbidden by divine or natural law; rather, Peter was given a limited and defined sphere of authority and power. Therefore, Ockham argues, the pope has no authority to deprive any human being of his natural rights or of the rights and liberties given to man by God. "As Christ did not come into the world in order to take away from men their goods and rights, so Christ's vicar, who is inferior and in no way equal to him in power, has no authority or power to deprive 436
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others of their goods and rights" (De Imperatorum ..., p. 10,11. 1215). Ockham specifies three of these inalienable rights: first, all those rights which non-Christians justly and admittedly enjoyed before the coming of Christ—for any of these rights to be taken from Christians by papal authority would be to make the liberty of Christians less than that of pagans and infidels; second, the disposition of temporal things belongs not to the papal authority but to the laity, according to the words of Christ that the things that are Caesar's should be rendered unto Caesar; third, although the pope is charged with the teaching of God's word, maintenance of divine worship, and provision of such things as are necessary for the Christian in his quest for eternal life, the pope has no power to command or requisition those things which are not necessary to this end, "lest he should turn the law of the Gospels into a law of slavery." On the important question of who is to be the judge of what is necessary for the legitimate ends of the church, Ockham holds that this cannot be the prerogative of the pope, of those under his command, or of the civil rulers. The ultimate decision should be sought in the Gospel, interpreted not by the clergy alone but by "the discretion and counsel of the wisest men sincerely zealous for justice without respect to persons, if such can be found—whether they be poor or rich, subjects or rulers" (ibid., p. 27,11. 17-20). This not very practical proposal nevertheless suggests that the membership of the Christian community as private individuals, rather than as officeholders, constitutes the true church. Yet Ockham is not, like Marsilius of Padua, against the principle of the pope as head of the church and vicar of Christ; he only seeks safeguards against abuse of the papal office and illegitimate assumption of tyrannical powers by holders of that office. Legitimate sovereignty, whether papal or civil, is not despotism; the dominion a master has over a slave is not the kind of authority exercised legitimately by a king, pope, or bishop. A pope may turn out to be a heretic and may be deposed—not by the emperor but only by a general council of the church. The imperial power derives from God, not directly but by way of the people who confer upon the emperor his power to legislate; the imperial power is not, as the popes had claimed, derived from the papacy. Ockham's political theory, insofar as it was formulated at all in his polemical writings, was not secularist or anticlerical; it was against absolutism in either church or state and much concerned that the "law of force," which is 43 7
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characteristic of the civil state, should not be adopted by the papal authority, lest the law of God, which is a law of liberty, be corrupted and degraded by temporal ambitions and lust for power. BIBLIOGRAPHY
Works by
Ockham
Quodlibeta Septem. Paris, 1487; Strasbourg, 1491. Summa Totius Logicae. Paris, 1488; Bologna, 1498; Venice, 1508, 1522, 1591; Oxford, 1675. Modern ed. of Pars Prima and Pars IIa et Tertiae Prima, Philotheus Boehner, ed. St Bonaventure, N.Y., 1951-1954. De Sacramento Altaris et De Corpore Christi. Strasbourg, 1491 (with Quodlibeta). N e w ed., with English translation by T . B. Birch, The De Sacramento Altaris of William of Ockham. Burlington, Iowa, 1930. Summulae in Libros Physicorum (or Philosophia Naturalis). Bologna, 1494; Venice, 1506; Rome, 1637. Dialogus Inter Magistrum et Discipulum. Lyons, 1495. Super Quatuor Libros Sententiarum . . . Quaestiones. Lyons, 1495 (with Centiloquium Theologicum). Expositio Aurea ... Super Artem Veterem. Bologna, 1496. The De Imperatorum et Pontificum Potestate of William of Ockham, C. K. Brampton, ed. Oxford, 1927. Breviloquium de Potestate Papae, L. Baudry, ed. Paris, 1937. Guillelmi de Ockham Opera Politica. Vol. I, J. G. Sikes, ed. Manchester, 1940; Vol. III, H . S. Offler, ed., Manchester, 1956. Other vols, in preparation. Tractatus de Praedestinatione et de Praescientia Dei et de Futuris Contingentibus, Philotheus Boehner, ed. St. Bonaventure, N.Y., 1945. Ockham: Philosophical Writings, Philotheus Boehner, ed. Edinburgh, 1957. Selections with translations. Expositio in Librum Porphyrii De Praedicabibus, E. A. Moody, ed. St. Bonaventure, N.Y., 1965.
Works on
Ockham
Abbagnano, Nicola, Guglielmo di Ockham. Lanciano, Italy, 1931. Baudry, L., Le Tractatus de Principiis Theologiae attribué à G. d'Occam. Paris, 1936. 438
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Baudry, L., Guillaume d'Occam, Vol. I, L'Homme et les oeuvres. Paris, 1950. Contains extensive bibliography of works on Ockham; full information on Ockham's published and unpublished works will be found on pp. 273-294. Baudry, L., Lexique philosophique de Guillaume d'Ockham. Paris, 1958. Boehner, Philotheus, Collected Articles on Ockham. St. Bonaventure, N . Y., 1956. Federhofer, Franz, Die Erkenntnislehre des Wilhelm von Ockham. Munich, 1924. Gottfried, Martin, Wilhelm von Ockham. Berlin, 1949. Guelluy, Robert, Philosophie et théologie chez Guillaume d'Ockham. Louvain and Paris, 1947. Hochstetter, Erich, Studien zur Metaphysik und Erkenntnislehre Wilhelms von Ockham. Berlin, 1927. Lagarde, Georges de, La Naissance de l'esprit läique au déclin du moyen âge, Vols. IV-VI. Paris, 1942-1946. Moody, E. A., The Logic of William of Ockham. New York and London, 1935. Moody, E. A., Truth and Consequence in Medieval Logic. Amsterdam, 1953. Moser, Simon, Grundbegriffe der Naturphilosophie bei Wilhelm von Ockham. Innsbruck, 1932. Scholz, Richard, Wilhelm von Ockham als politischer Denker und sein Breviloquium de Principatu Tyrannico. Leipzig, 1944. Shapiro, Herman, Motion, Time and Place According to Willliam Ockham. St. Bonaventure, N.Y., 1957. Vasoli, Cesare, Gugliemo d'Occam. Florence, 1953. Contains an extensive bibliography of works on Ockham. Vignaux, Paul, "Nominalisme" and "Occam," in Dictionnaire de théologie catholique, 15 vols. Paris, 1903-1950. Vol. XI, Cols. 733-789 and 864-904. Vignaux, Paul, Justification et prédestination au XIVe siècle. Paris, 1934. Vignaux, Paul, Le Nominalisme au XIVe siècle. Montreal, 1948. Webering, Damascene, The Theory of Demonstration According to William Ockahm. St Bonaventure, N.Y., 1953. Zuidema, Sytse, De Philosophie van Occam in 2.ijn Commentaar op de Sententien, 2 vols. Hilversum, Netherlands, 1936.
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Jean Buridan
i Although Jean Buridan was the most distinguished and influential teacher of natural philosophy at the university of Paris in the fourteenth century, little is known of his personal life. Born shortly before 1300 at Bethune, in the diocese of Arras, he came as a young cleric to study at the university of Paris where he was first enrolled as a student in the college of Cardinal Lemoine and later became a member of the college of Navarre. It is probable that he obtained his degree as Master of Arts soon after 1320, since a document dated 2 February 1328 mentions him as Rector of the university in that year. Other documents relating to benefices whose revenues provided his financial support, bearing the dates of 1329, 1330, 1342, and 1348, describe him as a "very distinguished man," as "a celebrated philosopher," and as "lecturing at Paris on the books of natural, metaphysical, and moral philosophy." Two passages in his own writings indicate that at some date prior to 1334 he made a visit to the papal court at Avignon and, on the way, climbed Mt. Ventoux for the purpose of making some meteorological observations. In 1340 he was Rector of the university for a second time, and in that year he signed a statute of the Faculty of Arts which censured certain Masters for the practice of construing texts in a literal sense rather than in accordance with the intentions of the authors, warning that this practice gave rise to "intolerable errors not only in philosophy but with respect to Sacred Scripture." One of the articles of censure bears on a statement known to have been made by Nicolaus of Autrecourt, whose sceptical views on causal inferences were attacked by Buridan in his own writings. The last documentary mention of Buridan occurs in a statute dated 12 July 1358 where his 441
Jean Buridan name appears as witness to an agreement between the Picard and English nations of the University. It is not unlikely that he fell victim to the Black Plague which in 1358 took the lives of many of those who had managed to survive its first outbreak in 1349. Buridan was a secular cleric and not a member of any religious order, and he remained on the faculty of Arts to the end of his Ufe without, apparently, seeking to obtain a degree in theology. In his lifetime he was held in high esteem by his colleagues, students, and ecclesiastical superiors, and for nearly two centuries after his death his teachings in natural philosophy and'logic were of paramount influence in the universities of northern and eastern Europe. A document in the archives of the university of Cologne, dated 24 December 1425, speaks of the preceding century as "the age of Buridan," and when George Lockert, in 1516, edited one of Buridan's works he stated that Buridan still ruled the study of physics at Paris. The name of Buridan was attached, in later centuries, to the story of the ass who could not choose between two equal bundles of hay, and to a story, presumably legendary but perpetuated by the poet Francois Villon, according to which Buridan had become involved in scandalous relations with the wife of the French king Philip V, and had by the king's order been tied in a sack and thrown into the Seine. The extant writings of Buridan consist of the lectures he gave on subjects comprised in the curriculum of the faculty of Arts at Paris. In the fourteenth century this curriculum was largely based on study of the treatises of Aristotle, along with the Summulae logicales of Peter of Spain and other medieval textbooks of grammar, mathematics and astronomy. Buridan composed his own textbook of logic, a Sunnnula de dialéctica, as a "modern" revision and amplification of the text of Peter of Spain, and he also wrote two treatises on advanced topics of logic, entitled Consequentiae and Sophismata, which are among the most interesting contributions to late medieval logic. All of his other works are in the form of commentaries, and of critical books of Questions, on the principal treatises of the Aristotelian corpus. The literal commentaries are extant only in unpublished manuscript versions, but the books of Questions on Aristotle's Physics, Metaphysics, De anima, Parva naturalia, Nicomachean Ethics, and Politics were published, along with Buridan's writings in logic, after the invention of printing. The only modern edition of a work by Buridan is that of his Questions on Aristotle's De cáelo et mundo, 442
Jean Buridan previously unedited, which appeared in 1942. Most of the printed editions represent the lectures Buridan gave during the last part of his teaching career, though earlier versions are found among the unpublished manuscript materials. Until a critical study of the manuscripts is made, however, there is no sure way of determining any order of composition among Buridan's works, or of tracing the development of his thought over the thirty odd years of his academic career. Buridan made significant and original contributions to logic and physics, but one of his major achievements was that of vindicating the independence of natural philosophy as a respectable study in its own right, and of defining the objectives and methodology of the scientific enterprise in a manner which gave warrant for its autonomy in relation to dogmatic theology and metaphysics. This achievement was intimately connected with the movement of fourteenth century thought known as Nominalism, and with the controversies precipitated at the universities of Oxford and Paris by the doctrines associated with William of Ockham. Buridan's own philosophical position was thoroughly nominalistic, and indeed very similar to that of Jean de Mirecourt, a theologian of Paris whose teachings were condemned in 1347 by the chancellor of the university and the faculty of theology. That Buridan was able to escape the charges of theological scepticism that were directed against his fellow nominalists of the theological faculty was no doubt due, in part, to his personal qualities of prudence and diplomacy. But it was also due to his methodological, rather than metaphysical, way of employing the logic and the epistemological doctrines of nominalism in formulating the character and the evidential foundations of natural philosophy. The formal logic presented in Buridan's Summula de dialéctica is closely related, in topical structure and in terminology, to the socalled terminist logic of the thirteenth century represented by the textbooks of William of Sherwood and Peter of Spain. Though it presupposes the nominalist thesis that general terms are signs of individuals and not of common natures existing in individuals, it does not exhibit any strong evidence of direct influence by the logical writings of Ockham, and it may well have been developed independently of such influence on the basis of the modern logic (lógica moderna) already well established in the Arts faculties of Oxford and Paris. The doctrine of the supposition of terms, basic to this logic, is used in defining the functions of logical operators or syncategorematic signs 443
Jean Buridan in determining the truth conditions of categorical propositions of various forms, and in formulating the laws of syllogistic inference both assertoric and modal. Treatises on topical arguments, fallacies, and on the demonstrative syllogism, conclude the work. Buridan's Sophismata, designed to constitute a ninth part of the Sunrmula, was apparently written much later in his life, since it contains criticisms of the theory of propositional meanings, or complexe significabilia, which Gregory of Rimini introduced in 1344. This work presents a very fully developed analysis of meaning and truth which corresponds fairly closely to that of Ockham's Sumrna logicae, but it goes well beyond the work of Ockham in presenting original and highly advanced treatments of the problem of the non-substitutivity of terms occurring in intensional contexts, and of the problem of self-referential propositions represented by the paradox of the Liar. Buridan's treatment of these problems exhibits a level of logical insight and skill not again equalled until very recent times. His treatise on Consequentiae, whcih develops the whole theory of inference on the basis of propositional logic, marks another high point of medieval logic whose significance has only been appreciated in the twentieth century. Buridan's philosophy of science is formulated in his Questions on the Metaphysics, and applied to the concepts and problems of natural science in his Questions on the Physics. The Aristotelian definition of science as knowledge of universal and necessary conclusions by demonstration from necessary, evident, indemonstrable premises, is accepted; but a sharp distinction is made between premises whose necessity is determined by logical criteria or by stipulated meaning of the terms, and those whose evidence rests on empirical confirmation and which are called necessary in a conditional sense, or "on the supposition of the common course of nature." The principles of the natural sciences have evidence and necessity only in the latter sense. These principles are not immediately evident; indeed we may be in doubt concerning them for a long time. But they are called principles because they are indemonstrable, and cannot be deduced from other premises nor be proved by any formal procedure; but they are accepted because they have been observed to be true in many instances and to be false in none. (Qu. in Metapa. II, Qu. 2; ed. 1518, fol. 9v). The significance of this theory of scientific evidence lies in its re444
Jean Buridan jection of the thesis held by most of the scholastic commentators of Aristotle that the principles of physics are established by metaphysics, and that they are necessary in the sense that their contradictories are logically or metaphysically impossible. It was this metaphysical interpretation of Aristotelian physics that had brought about the condemnation, by Bishop Etienne Tempier and the Faculty of Theology at Paris, in 1277, of doctrines taught by members of the Arts Faculty as necessary truths of philosophy, though contradictory to dogmas of the Christian Faith. By construing the principles of the sciences of nature as inductive generalizations whose evidence is conditional on the hypothesis of the common course of nature, Buridan was able to concede the absolute possibility of supernatural interference with the natural causal order, and yet to exclude such supernatural cases as irrelevant to the purposes and methodological procedures of the scientific enterprise. Nicolaus of Autrecourt, demanding that scientific principles have absolute necessity and certainty, had argued that a science of nature based on causal laws established by inductive generalization has no evidence whatsoever, since it could not be known in any given instance whether or not God is producing an effect without a natural cause. Buridan refers to Nicolaus' position in these words: It has hereby been shown that very evil things are being said by certain ones who seek to undermine the natural and moral sciences because absolute evidence is not possessed by most of their principles and conclusions, it being supernaturally possible for them to be rendered false. For in these sciences absolutely unconditional evidence is not required, and it is enough if we have conditional or hypothetical evidence of the kind described above. (Qu. in Metaph. II, Qu. 1; ed. 1518, fol. 9r) The conception of the scientific enterprise formulated by Buridan as a means of justifying its pursuit within the framework of the Christian doctrine of divine omnipotence is very much the conception within which science has operated since the late seventeenth century. T o make science compatible with Christian dogma Buridan had to break its traditional ties with metaphysics and define its principles methodologically in terms of their value in "saving the phenomena." He still encountered difficulties from some theological dogmas in applying this method within the domain of physics, as did Galileo 445
Jean Buridan three centuries later; but after the time of Buridan natural philosophy had its own charter of legitimacy, and ceased to be a mere handmaiden of theology while also ceasing to be a mere exposition of the doctrines of Aristotle. The books of Questions composed by Buridan on problems raised in Aristotle's Physics and De caelo et mundo exhibit his application of these criteria of scientific method and evidence, in the critical evaluation of Aristotle's theories and arguments and of the diverse interpretations of them offered by Greek, Moslem and Christian scholastic commentators. The general scheme and conceptual framework of analysis, within which Aristotle's physics and cosmology are formulated, is accepted by Buridan as the working hypothesis, so to speak, of natural philosophy. But the scheme is not sacrosanct, and not infrequently Buridan entertains alternative assumptions as not only logically possible but as possibly preferable in accounting for the observed phenomena. While the authority of Aristotle had often enough been challenged on the ground that his positions contradicted Christian doctrine, it had come, in Buridan's time, to be challenged on grounds of inadequacy as a scientific account of observed facts. Buridan's major significance in the historical development of physics arises from just such a challenge with respect to Aristotle's dynamic theory of local motion, and from his proposal of an alternative dynamics which came to be known as the impetus theory. An obvious weakness of Aristotle's dynamics is its inability to account for projectile motions, such as the upward motion of a stone thrown into the air, after it has left the hand of the thrower. Such a motion, being violent and contrary to the natural movement of the stone toward the earth, required an external moving cause continuously in contact with it, according to the assumptions of Aristotelian physics. Since the only body in contact with it is the air, Aristotle supposed that in some way the air pushes or pulls the body upward. This feeble explantion drew criticism in antiquity and from medieval Moslem commentators, giving rise to a theory that the violent action of the thrower impresses on the stone a temporary disposition, of qualitative sort, which causes it to move for a short time in the direction contrary to its nature. This disposition was called an "impressed virtue" (virtus impressa), and it was held to be self-expending and quickly used up because of its separation from its source. A Franciscan theologian who taught at Paris around 1322, Franciscus de 446
Jean Buridan Marchia, gave a very full presentation of this theory, and it is likely that Buridan was influenced by it. In treating of the problem of projectile motion in his Questions on Aristotle's Physics (Book VIII, Qu. 12), Buridan expounded Aristotle's theory of propulsion by the air and rejected it with arguments very similar to those which Marchia had used. His own solution was in some respects like that of Marchia, but in one crucial point it was strikingly different. The tendency of the projectile to continue moving in the direction in which it is propelled, which Buridan calls impetus rather than virtus impressa, is described as a permanent state or power of motion, which would continue unchanged if it were not opposed by the gravity of the projectile and the resistance of the air. "This impetus," he says in another discussion given in his Questions on the Metaphysics (ed. 1518, fol. 73r), "would endure forever (ad infinitum) if it were not diminished and corrupted by an opposed resistance or by something tending to an opposed motion." The suggestion here given of the inertial principle fundamental to modern mechanics is striking, as are some further uses which Buridan makes of the impetus concept in explaining the accelerated velocity of free fall, the vibration of plucked strings, the bouncing of balls, and the everlasting rotational movements ascribed to the celestial spheres by Greek astronomy. Buridan defines impetus in a quantitative manner, as a function of the "quantity of matter" of the body and of the velocity of its motion; thus he seems to conceive impetus as equivalent to what in classical mechanics is called momentum and defined as product of mass and velocity. In treating of the action of gravity in the case of freely falling bodies, Buridan construes this action as one of imparting successive increments of impetus to the body during its fall. It must be imagined that a heavy body acquires from its primary mover, namely from its gravity, not merely motion, but also, with that motion, a certain impetus such as is able to move that body along with the natural constant gravity. And because the impetus is acquired commensurately with motion, it follows that the faster the motion, the greater and stronger is the impetus. Thus the heavy body is moved initially only by its natural gravity, and hence slowly; but it is then moved by that same gravity as well as by the impetus already acquired, and thus it is . . . continuously
accelerated to the end. (Qu. de caelo et mundo% ed. 1942, p. 180.)
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Jean Buridan The effect of a force, such as gravity, is thus conceived as a production of successive increments of impetus, or of velocity in the mass acted upon, throughout the fall. It is a short step from this to the modern definition of force as that which changes the velocity of the body acted upon, implying the correlative principle that a body in uniform motion is under the action of no force. Buridan does not quite take this step, since he retains the Aristotelian assumption that a constant cause must produce a constant effect, and ascribes the increase in velocity to the addition of impetus as an added cause acting along with the gravity. Yet his theory obviously requires a distinction between impetus as a "conserving cause" of motion, and gravity as a "producing cause" of the motion conserved by the impetus; his failure to draw the consequence of this distinction was perhaps due to the fact that he did not attempt a mathematical analysis involving the concept of instantaneous velocities added continuously with the time. Whether Buridan construed the acceleration as uniform with respect to time elapsed, or with respect to distance traversed, is not clear. He probably regarded the two functions as equivalent, a view which, however impossible from a mathematical point of view, was retained into the seventeenth century, when Descartes, and also Galileo in his letter to Sarpi of 1604, sought to prove that velocity increases in proportion to time elapsed, from the premise that it increases as a function of distance of fall. Buridan's concept of impetus is further distinguished from the modern inertial concept by the fact that he construes rotational motion at uniform angular velocity as due to a rotational impetus analogous to the rectilinear impetus involved in projectile motion. Galileo did likewise, and was in this respect nearer to Buridan than to Newton. But Buridan makes a striking use of his impetus concept, in its rotational sense, by arguing that since the celestial spheres posited by the astronomers encounter no external resistance to the rotational movements, and have no internal tendency toward a place of rest such as heavy and light bodies have, their uniform rotational motions are purely inertial and require no causes acting on them to maintain their motions. There is therefore no need to posit immaterial intelligences as unmoved movers of the heavenly spheres, in that manner which Aristotle and his commentators supposed. "For it could be said that God, in creating the world, set each celestial orb in m o t i o n . . . and, in setting them in motion, he gave them an impetus 448
Jean Buridan capable of keeping them in motion without there being any need of his moving them any more" (Qu. in Phys. VIII, Qu. 12; fol. 121 r). It was in this way, Buridan adds, that God rested on the seventh day and committed the motions of the bodies he had created to those bodies themselves. It is clear that Buridan's impetus theory marked a significant step toward the dynamics of Galileo and Newton, and an important stage in the gradual dissolution of Aristotelian physics and cosmology. Buridan did not however exploit the potentially revolutionary implications of his analysis of projectile motion and gravitational acceleration, or generalize his impetus theory into a universal inertial mechanics. Thus, in discussing the argument of Aristotle against the possibility of motion in a void, Buridan accepted the principle that the velocity of a natural motion in a corporeal medium is determined by the ratio between the motive force and the resisting force of the medium, so that if there were no resisting medium the motion would be instantaneous. This is scarcely consistent with the analysis of gravitational acceleration in terms of finite increments of impetus given to the falling body by its gravity, and Buridan made no effort to harmonize these two different approaches under a common theory. In a question bearing on the De caelo et mundo of Aristotle Buridan asks whether it can be proved that the earth is at rest, with the celestial spheres rotating around it, as is supposed by Aristotle. He states that many people of his time held it to be probable that the earth rotates on its own axis once a day, and that the stellar sphere is at rest. And he adds that "it is indisputably true that if the facts were as this theory supposes, everything in the heavens would appear to us just as it now appears" (Qu. de caelo et mundo, II, Qu. 22; ed. 1942, p. 227). In support of the hypothesis he invokes the principle that it is better to account for the observed phenomena by fewer assumptions, or by the simplest theory, and argues that since the earth is a small body, and the outer sphere a very large one, it is more reasonable to attribute the rotation to the earth than to suppose the enormously faster rotation of the much larger body of the sphere. After giving this and other arguments in favor of the theory of diurnal rotation of the earth, Buridan makes it quite clear that they cannot be refuted by any of the traditional arguments purporting to prove that the earth is at rest. But he says that for his part he chooses to hold that the earth is at rest and the heavens in motion, and he offers, as a "persuasion" for this view, 449
Jean Buridan the argument that a projectile thrown straight upward from the earth's surface will fall back to the same spot from which it was thrown. His argument does not seem consistent with his own impetus theory, unless he had in mind a point made later by his pupil Albert of Saxony, who held that the lateral impetus shared by the projectile with that of the surface of the rotating earth would be insufficient to carry it over the greater arc which it would have to traverse, when projected outward from the earth's surface, in order to fall back at the same spot. Not only Albert of Saxony, but another pupil of Buridan, Nicolaus of Oresme, took over this discussion of the earth's rotation; and Oresme concluded that it is impossible to prove either side of the question, since the motion is purely relative. Oresme said that he accepted the view of the earth being at rest, but only because this seemed to be assumed by the Bible. It is of interest to note that when Copernicus was a student at Cracow, Buridan's works in physics were required reading in the curriculum of that university. While rejecting the theory of the diurnal rotation of the earth, Buridan says that the earth is not immobile at the center of the world, and proves it as follows. Because the dry land protruding from the ocean is mostly on one side of the earth, the center of volume of the earth does not coincide with its center of gravity. The earth, however, is the center of the world in the sense that its center of gravity is equidistant from the inner surface of the celestial spheres. But this center of gravity is continuously altered by the erosion of the dry land which slowly gets washed into the sea, and consequently the whole mass of the earth slowly shifts from the wet side to the dry side in order to keep its center of gravity at the center of the universe. Buridan's significance in the history of science lies more in the questions he raised than in the answers he gave to them, though in some cases his answers opened up new possibilities of scientific theory which were undoubtedly influential in the rise of modern mechanics in the seventeenth century. The impetus theory was taken over by Buridan's pupils and made known throughout central Europe, though in a degenerate form which fused it with the older theory of a selfexpending virtus impressa, and introduced a number of confusions and errors which Buridan himself had avoided. It was in this degenerate form that it was conveyed to Galileo by his teacher Bonamico, so that Galileo had to take the step which Buridan had taken three centuries earlier when he discarded Marchia's theory of the self-ex450
Jean Buridan pending impressed force in favor of impetus as an enduring condition only changed or diminished by opposed forces. Buridan's application of the impetus concept to the analysis of free fall, though retained and made known by Albert of Saxony, tended to be forgotten by most of the later teachers of physics even when they retained the concept in dealing with projectile motion. But even where Buridan's specific contributions to physical problems were forgotten, the influence of his conception of scientific evidence and method remained operative, and it may be said that the idea of a mechanics, in the modern sense, became established in early modern times by reason of the work of Buridan and of his contemporaries. In particular, Buridan may be credited with eliminating explanations in terms of final causes, from the domain of physics, which he does very explicitly in his Questions on the Physics (Book II, Qu. 7 and 13), and in his Questions on Aristotle's De caelo et mundo (II, Qu. 8). The mechanistic conception of nature, construed as a methodological assumption more than as a metaphysical thesis, emerged in the fourteenth century as a natural development from Buridan's philosophy of science. He was not himself an experimental scientist, nor a mathematical physicist; but as a philosopher of science his work did much to clear the way, and to point the way, to the development of modern science in these directions.
BIBLIOGRAPHY Texts Summula de dialettica (with commentary of John Dorp of Leiden). Lyons, 1490, 1493, 1495, 1510; Venice, 1499 (under title Ferutile compendium totius logicae Joannis Buridani); many later editions. "Giovanni Buridano, Tractatus de suppositionibus," ed. Maria Eleina Reina. Rivista Critica di Storia della Filosofia, XII (1957), 175-208, 323352. Sophismata Buridani. Paris, 1489, 1491, 1493; best edition, by Antonius Denidel and Nicolaus de Barra. Paris, s. a. (c. 1495). John Buridan: Sophisms on Meaning and Truth. Trans. Theodore Kermit Scott. N. Y., 1966 (translation of Sophismata Buridani). Consequenttae Buridani. Paris, 1493,1495, 1499. Quaestiones super octo physicorum libros Aristotelis. Ed. Johannes Dul-
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Jean Buridan laert Gandavensis. Paris, 1509, 1516. Quaestiones super libris quattuor De caelo et mundo. Ed. Ernest A. Moody. Cambridge, Mass., 1942. Quaestiones et decisiones physicales insignium virorum .. . Ed. Georgius Lockert. Paris, 1516 (contains Buridan's Quaestiones in libros De anima, De sensu et sensato, De memoria et reminiscentia, De somno et vigilia, De longitudine et brevitate vitae, and De iuventate et senectute). In Metaphysicen Aristotelis Quaestiones argutissimae magistri Joannis Buridani. Paris, 1518. Quaestiones super decern libros Ethicorum Aristotelis ad Nicomachum. Paris, 1489,1513, 1518; Oxford, 1637. Quaestiones in octo libros Foliticorum. Paris, 1530; Oxford, 1640. Farai, Edmond: "Jean Buridan, Notes sur les manuscrits, les éditions et le contenu de ses oeuvres," Archives d'histoire doctrinale et littéraire du moyen-age, t. 15 (1946), pp. 1-53 (lists manuscripts of unpublished and published works). Studies Bulliot, J. "Jean Buridan et le mouvement de la terre," Revue de Philosophie, t. 25 (1914), pp. 5-24. Clagett, Marshall. The Science of Mechanics in the Middle Ages. Madison, Wise., 1959. Pp. 505-599. Dijksterhuis, E. J. De Mechanisiring van het Werelbild. Amsterdam, 1951. Duhem, Pierre. Etudes sur Léonard de Vinci. 3e Série. Paris, 1913. Pp. 1 259, 279-286, 350-360; 2a Série, Paris, 1909, pp. 379-384, 420-423, 431438. . Le Système du Monde, t. VI-VII. Paris, 1954-1958. Farai, Edmond. "Jean Buridan, maître-es-arts de l'Université de Paris," Histoire littéraire de la France, t. 38 (1949), pp. 462-605. Maier, Anneliese. Die Vorläufer Galileis im 14. Jahrhundert. Rome, 1949. . Zwei Grundprobleme der scholastischen Naturphilosophie. 2d ed. Rome, 1951. Pp. 201-235. . Metaphysische Hintergründe der spätscholastischen Naturphilosophie. Rome, 1955. Pp. 300-335, 348 ff., 384 ff. . Zwischen Philosophie und Mechanik. Rome, 1958. Pp. 332-339. . "Die naturphilosophische Bedeutung der scholastischen Impetustheorie," Scholastik, B. 30,Hft. 3 (1955), pp. 321-343. Moody, Ernest A. "John Buridan on the Habitability of the Earth," Speculum, XVI, 4 (October, 1941 ), 415-425. . "Ockham, Buridan and Nicholas of Autrecourt," Franciscan Studies, 452
Jean Buridan 7 (June, 1947), 113-146. . "Galileo and Avempace: The Dynamics of the Leaning Tower Experiment," Journal of the History of Ideas, XII (1951), 163-193, 375— 422. . "Buridan and a Dilemma of Nominalism," Harry Austryn Wolf son Jubilee Volume. Jerusalem, 1965. Pp. 577-596. . Truth and Consequence in Medieval Logic. Amsterdam, 1953. Prantl, Carl. Geschichte der Logik im Abendlande. Bd. IV. Leipzig, 1870. Pp. 14-38. Prior, A. N. "Some Problems of Self-Reference in John Buridan," Proceedings of the British Academy, XL Vili (1962), 281-296. Reina, Maria Eleina: "Il Problema del Linguaggio in Buridano," Rivista Critica di Storia della Filosofia, XIV (1959), 367-417; X V (1960), 141165, 238-264. . "Note sulla psicologia di Buridano," Arti Grafiche Grisetti. Milan, 1959. P. 9 ff. Scott, Theodore Kermit. "John Buridan on the Objects of Demonstrative Science," Speculum, XL ( 1965), 654-673. Vescovini, G. Federici. "La concezione della natura di Giovanni Buridano," La filosofia della natura nel Medievo: Atti del 111 Congresso internazionale di filosofia medievale. Milan (Vita e pensiero), 1964. Vescovini, G. Federici. Studi sulla prospettiva medievale. Torino, 1965. Pp. 137-163. Walsh, James J. "Nominalism and the Ethics: Some Remarks about Buridan's Commentary," Journal of the History of Philosophy, IV (1966), 1-13. . "Buridan and Seneca," Journal of the History of Ideas, XXVII, (1966), 23-40. . "Is Buridan a Sceptic about free will?" Vivarium, II (1964), 50-61.
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