At the Origins of Mathematical Economics: The Economics of A.N. Isnard (1748-1803) (Routledge Studies in the History of Economics)

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At the Origins of Mathematical Economics Achilles Nicholas Isnard’s seminal contributions to the study of economics remained largely unacknowledged until the latter half of the twentieth century. He is best known for demonstrating the concept of market equilibrium using simultaneous equations, and as a forerunner of Input-Output analysis. However, the breadth and depth of Isnard’s work has so far been completely unrecognised This pioneering new book examines Isnard’s life and illuminates his major contributions to political economy. At the Origins of Mathematical Economics contains substantial extracts from a number of Isnard’s publications presented both in English translation and in the original French. The diverse issues covered in Isnard’s work will ensure that this book will appeal not only to economists with an interest in the history of mathematical economics, but also to anyone interested in the emergence of political economy and in wider social thought during the Enlightenment. Richard van den Berg is a principal lecturer at Kingston University, UK.

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59 Marshall’s Evolutionary Economics Tiziano Raffaelli 60 Money, Time and Rationality in Max Weber Austrian connections Stephen D.Parsons 61 Classical Macroeconomics Some modern variations and distortions James C.W.Ahiakpor 62 The Historical School of Economics in England and Japan Tamotsu Nishizawa 63 Classical Economics and Modern Theory Studies in long-period analysis Heinz D.Kurz and Neri Salvadori 64 A Bibliography of Female Economic Thought to 1940 Kirsten K.Madden, Janet A.Sietz and Michele Pujol 65 Economics, Economists and Expectations From microfoundations to macroeconomics Warren young, Robert Leeson and William Darity Jnr 66 The Political Economy of Public Finance in Britain, 1767–1873 Takuo Dome 67 Essays in the History of Economics Warren J.Samuels, Willie Henderson, Kirk D.Johnson and Marianne Johnson 68 History and Political Economy Essays in honour of P.D. Groenewegen Edited by Tony Aspromourgos and John Lodewijks 69 The Tradition of Free Trade Lars Magnusson 70 Evolution of the Market Process Austrian and Swedish economics Edited by Michel Bellet, Sandye GloriaPalermo and Abdallah Zouache 71 Consumption as an Investment The fear of goods from Hesiod to Adam Smith Cosimo Perrotta

72 Jean-Baptiste Say and the Classical Canon in Economics The British connection in French classicism Samuel Hollander 73 Knut Wicksell on Poverty No place is too exalted Knut Wicksell 74 Economists in Cambridge A study through their correspondence 1907–1946 Edited by M.C.Marcuzzo and A.Rosselli 75 The Experiment in the History of Economics Edited by Philippe Fontaine and Robert Leonard 76 At the Origins of Mathematical Economics The economics of A.N.Isnard (1748–1803) Richard van den Berg

At the Origins of Mathematical Economics The economics of A.N.Isnard (1748–1803)

Richard van den Berg

LONDON AND NEW YORK

First published 2006 by Routledge 2 Park Square, Milton Park, Abingdon, Oxon OX 14 4RN Simultaneously published in the USA and Canada by Routledge 270 Madison Ave, New York, NY 10016 Routledge is an imprint of the Taylor & Francis Group This edition published in the Taylor & Francis e-Library, 2006. “To purchase your own copy of this or any of Taylor & Francis or Routledge’s collection of thousands of eBooks please go to www.eBookstore.tandf.co.uk.” © 2006 Richard van den Berg All rights reserved. No part of this book may be reprinted or reproduced or utilised in any form or by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying and recording, or in any information storage or retrieval system, without permission in writing from the publishers. British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library Library of Congress Cataloging in Publication Data A catalog record for this book has been requested ISBN 0-203-61758-4 Master e-book ISBN

ISBN 0-203-34917-2 (Adobe eReader Format) ISBN 10:0-415-30649-3 (Print Edition) ISBN 13:9-78-0-415-30649-2 (Print Edition)

For Amber

Contents

Foreword

xiv

Acknowledgements

xvii

Introduction PART A The economics of A.N.Isnard 1 Life and career of Achilles Nicolas Isnard (1748–1803)

1 6

8

2 Main themes in Isnard’s writings

20

3 Reception and influence of Isnard’s writings

55

PART B Text and translation

59

Appendix: a bibliography of Isnard’s writings

357

Notes

361

References

384

Index

391

Foreword

The 1897 Palgrave Dictionary of Political Economy devoted one short paragraph (by E.Castelot) to Achilles Nicolas Isnard, which mentioned his two books on economics, that he was an engineer, had ‘frequent recourse to mathematical symbols’ but did ‘not venture further than equations of the first degree and simple problems in the rule of three’. No date of birth was given and only an approximate date of death. Isnard’s mathematical proclivities had earlier been recognised by Jevons, who had listed him as a mathematical economist in an appendix to the second edition of his Theory of Political Economy (1879). Jevons’ source for this listing had been no less a mathematical economist than Walras, on whose work Isnard had exerted some influence. This was demonstrated almost a century later in an interesting article by Jaffé which, I may add on a personal note, introduced Isnard’s name to me as an interesting late eighteenth-century economist. By then, Isnard had been given wider recognition as an early practitioner of mathematical economics by a number of authors (such as Theocharis in 1961, Baumol and Goldfeld in 1968). When in 1987 the New Palgrave Dictionary of Political Economy accorded Isnard a substantial two-page entry (by Hébert), his mathematical economics, his influence on Walras and his status as yet another French engineer who contributed to economics were appropriately celebrated. However, Isnard had been already revered as an important and valuable contributor to economics during the first half of the nineteenth century. In his The Literature of Political Economy (1845), J.R.McCulloch had listed Isnard’s Traité des richesses (1781) as ‘a learned and valuable work’ despite its ‘desultory’ and imprecise style which, unlike most of its contem porary works in the late eighteenth century on the European continent severely criticised the work of the physiocrats, with special emphasis to their wrong doctrine on the exclusive productivity of agriculture and its corol lary, the impossibility of imposing taxation except on the net product of the land in the hands of the landlords. Moreover, McCulloch praised Isnard’s work for its acute and lengthy examination of the apologetics favouring restrictions on international trade with respect to certain commodities, for its able vindication of the employment of machinery, and for its elaborate account of taxation in the context of the mode of acquiring property. McCulloch’s commentary on Isnard’s major work, admittedly in a somewhat rare bibliography of political economy, indicated that Isnard’s economics encompassed far more than some early steps in mathematical reasoning on value theory and some timid foreshadowing of the foundation of general equilibrium analysis. The validity of McCulloch’s judgement, and the inadequacy of much of the

more recent interpretations of his work can now be fully appreciated in Richard van den Berg’s splendid edition of selections of Isnard’s economic works, accompanied as it is by the editor’s very useful introduction and splendid editorial notes. Of that content, this foreword needs to say very little since it can be enjoyed by the reader in what follows. Allow me to emphasise, however, two of its more pertinent features. First, Part A provides not only essential historical information for the appreciation of Isnard’s economics (on some aspects of which I want to comment later), but also a fine biographical sketch of Isnard constructed through Richard van den Berg’s diligent research. It incidentally provides two further contacts between Isnard’s life and that of Walras: the importance of Switzerland and Lausanne to their economic careers, and the role played by the town of Evreux in their respective lives. Second, the body of the work incorporates the French text and a (first) English translation of lengthy extracts from no less than six economic texts by Isnard. Apart from the 1781 Traité des richesses, by far the best known of Isnard’s works, they include the 1784 Catéchisme social; the 1789 Réponses aux principales objections à faire contre l’impôt unique’, the 1790 Reflexions sur l‘émission des assignats; the 1791 Du nouveau systême d’impôts établi par l’assemblée nationale de France, en 1791 and the 1801 Considerations théoriques sur les caisses d’amortissement de la dette publique. To indicate the importance and novelty of this selection, only the first and the last of these writings were mentioned in Hébert’s bibliography for his 1987 entry in the New Palgrave. In this way alone, Richard van den Berg’s book will facilitate the wider recognition of Isnard’s economic contributions, an opportunity for which all historians of economics will be grateful to him. Let me bring this foreword to a close by commenting briefly on two aspects of the splendid introduction Richard van den Berg provides in Part A. In its opening paragraph to section 2.1.1 (p. 24), van den Berg provides a list of ‘modern authorities’ cited by Isnard in his Traité. It includes d’Alembert, Bacon, Baudeau, Boisguilbert, Bolingbroke, Charron, Child, Culpeper, Decker, Dupré de Saint Maur, Euler, Forbonnais, Graslin, Helvétius, Holbach, l’Hôpital, Hume, Law, Leroy, Linguet, Locke, Melon, Montesquieu, Morellet, Morelly, Moulin, Necker, de Pinto, Plumart de Dangeul (‘Nicols’), Quesnay, Raynal, Robertson, Rousseau, Vauban, Voltaire and ‘Johan de Wit’. This is a very impressive list, if only because it covers both British and French writers, and most of the leading economic authorities from the late seventeenth and early eighteenth centuries. The most striking omissions from the list are Cantillon and Turgot. Given the relative scarcity of Cantillon’s work (it had been published only once in 1755), van den Berg does not comment on this absence in much detail. However, the omission of Turgot he finds intriguing and in various notes he draws attention to similarities between Isnard’s argument and material to be found in Turgot’s economic writings. This is the second aspect from Part A on which I wish to comment. Van den Berg wisely limits the economics of Turgot from which Isnard could have benefited to two sources: Turgot’s Reflections on the Formation and Distribution of Wealth (1766) and his unfinished paper on ‘Value and Money’ (1769). By 1781, Isnard could have read the first in the version published by Du Pont in three instalments in the pages of the physiocratic journal, Ephémérides du Citoyen (1769–70). This did not mention Turgot by name as the author, hence explaining the lack of citation by author’s name, if the work had indeed been studied by Isnard. Some of the contents of Turgot’s ‘Value and Money’, a work not

published until 1808 in the collected works of Turgot edited by Du Pont, could have been made accessible to Isnard indirectly via Morellet’s use of it for his commercial dictionary. Hence it may be possible to add Turgot’s name to the list of Isnard’s earlymodern authorities with respect to these two works. My own impression from reading Isnard’s text is that the case is stronger for ‘Value and Money’ than for Reflections, not only in terms of the textual evidence but also from the difficulties I personally perceive for placing copies of Ephémérides in Isnard’s hands, given the lack of evidence on this in Part A. The reader may find this an additional interesting puzzle thrown up by this splendid edition of Isnard’s economics. Enough has been said to indicate that study of this book is very worthwhile and rewarding by enabling a more complete opening up of Isnard’s rich contributions to the economic literature of his time. That these have been insufficiently appreciated up till now has already been suggested in my remarks. The joys of making that discovery for themselves can be safely left to the many readers this book so richly deserves, and for the preparation of which Richard van den Berg deserves our hearty congratulations. Peter Groenewegen Professor Emeritus, Economics University of Sydney

Acknowledgements

I thank Sylvie Caucanas, Silvio Corsini, Arnoud Gerits, Catherine Masteau, Jean-Pierre Potier and Christophe Salvat for supplying me with various pieces of information, and Shelagh Eltis, Mario Damen and especially Jugdeep Dhesi and Fabien De Castilla for providing assistance in the preparation of the text. I also thank Robert Langham and Susan Leaper for their patience and professionalism.

Title page of the Traité des Richesses

Isnard’s signature (Reproduced with permission of the Library of the École Nationale des Ponts et Chaussées)

Introduction In December 1878 the Journal des économistes published a ‘bibliography of works relative to the application of mathematics to political economy’. The first item on this list was a two-volume work with the title Traité des richesses. Léon Walras (1834–1910), the founder of modern general equilibrium theory and compiler of the list, commented on this book: […] I have inserted at the head of the list the work of Isnard, published in 1781. In the early pages of this book ratios of values are correctly stated in algebraic symbols as equal to the inverse ratios of the quantities of commodities exchanged. The equation of exchange, though by no means fully or deeply considered by the author, remains nevertheless, the starting point of the scientific theory of social wealth. Despite its inadequacies, this equation is enough to effect, within certain limits, the transformation of theoretical political economy into a mathematical science. (Walras 1878:470; translation in Jaffé 1969:25) The inclusion of the Traité des richesses in this list, with the intriguing accompanying statement, marks the beginning of Isnard’s reputation as an early contributor to mathematical economics.1 Walras’ list and the ‘List of Mathematico-Economic Books’ published by Stanley Jevons shortly after in 18792 effectively saved Isnard from oblivion. For historians of economic thought with a specialist interest in the application of mathematics, it was henceforth not difficult to find out about the existence of the Traité3 Moreover, in due course a succession of books and articles emerged anthologising what were believed to be the most significant texts in mathematical economics before the 1870s. Short excerpts of the mathematical passages in the Traité on which Walras had commented were included in these collections, typically sandwiched between Beccaria’s analysis of smuggling and Canard’s economic algebra or Frisi’s attempt to apply differential calculus to Verri’s price function (Boven 1912; Moret 1915; Robertson 1949; Reichardt 1954; Theocharis 1961; Baumol and Goldfeld 1968). Preserved for posterity in this manner, Isnard’s contribution will have attracted a small amount of interest in the first half of the twentieth century, but mainly as a curiosity. It was not until Joseph A.Schumpeter’s discussion of Isnard in his magisterial History of Economic Analysis that something more significant began to be read into his contribution.4 In Schumpeter’s opinion Isnard had’ […] as yet to conquer the position in the history of economic theory that is due to him as a precursor of Léon Walras’ (Schumpeter 1954:217). While Schumpeter stopped short of claiming that Walras had actually been influenced by Isnard, the very association of the two names may be said to have raised the latter’s stock from curious early dabbler in economic algebra to minor visionary.5 It was to be raised yet further when some years later William Jaffé put forward a detailed case to prove that Isnard had been more than a precursor to Walras.

At the origins of mathematical economics

2

Isnard, he argued, should be recognised as a ‘progenitor of the Walrasian general equilibrium model’, having developed key notions that were adopted much later by the professor from Lausanne. Walras, as Jaffé (1969:42) put it, ‘[…] worked out the mathematical framework of his general equilibrium theory with Isnard’s Traité des richesses at his elbow […]’. This remarkable reassessment of the importance of Isnard’s mathematical contributions has since found its way into dictionaries and general histories of economic thought (see e.g. Hébert 1987; Ingrao and Israel 1990; Screpanti and Zamagni 1993). This, in a nutshell, is how the reputation of Achilles Nicolas Isnard, as it stands today, was established. A few curious aspects of the modern reception of his ideas should be mentioned. First, most commentators on Isnard’s contribution have shown precious little interest in anything written by the author apart from the short passages containing his algebra and numerical examples. Perhaps this is because there has been an over-reliance on the anthologies of early mathematical economics mentioned above, where the crucial passages of the Traité are readily available. Second, apart from a few exceptions,6 it is the association with Léon Walras that seems to have been the exclusive reason why the majority of commentators have taken any interest in Isnard’s contribution. As a result, the question of the historical significance of Isnard has become reduced to the limited issue of whether, and if so, to what extent, he can be considered a precursor to Walras. The question of how Isnard’s novel ideas relate to the wider intellectual context of economic theory during the French Enlightenment has been all but ignored. For these two reasons Isnard emerges as an extremely ‘flat character’ in general histories of economic thought. He briefly appears on the overcrowded stage without the audience knowing anything about his background or the context of his message. Upon delivering his short message, something of an early announcement of a much more important theorist to come, he once again retreats into obscurity. If one tries to trace Isnard in more specialist secondary literature, one finds that there is not much available. The only study of any length about his life and works is the no longer very useful PhD thesis of Louis Renevier (1909). The handful of modern articles that devote more than a few words to the engineer’s ideas focus exclusively on the short mathematical passages from the Traité des richesses (Jaffé 1969; Gilibert 1981; Perrot 1983; Klotz 1994; Kurz and Salvadori 2000; Steenge and van den Berg 2001). It is no exaggeration to say that beyond those passages Isnard’s writings have hardly ever been studied in any detail. As a result he has remained, as one commentator put it, ‘the least known of famous economists’ (Klotz 1994:29). The question why Isnard’s writings have never attracted more scholarly interest is not so easy to answer. It is true that there are practical difficulties involved with a comprehensive study of his writings (most of the engineer’s publications are very rare, no single library has a complete collection of his works), but this does not seem sufficient discouragement for determined researchers. Perhaps a more likely answer is that those students who have been attracted by Isnard’s mathematical contributions, did not find what they were looking for in the rest of his writings. At the same time, those who would have been interested in his economic thought more generally, may have avoided his writings believing him to be an author with a narrow interest in the area of mathematical economics.

Introduction

3

An example of the first kind of student is Schumpeter. Apparently having read the Traité, he sounds quite disappointed with his finding that Isnard’s ‘[…] historic performance […] is embedded in a conventional argument against physiocrat doctrines and other neither very original nor very interesting matter’ (Schumpeter 1954:217 n.3). The words ‘historic performance’ refer to Isnard’s algebraic analysis of market equilibrium. One suspects that Schumpeter hoped to find more economic analysis of an explicit mathematical kind in the Traité. There is indeed not more than a scattering of this in Isnard’s first publication. The remark that the mathematics is ‘embedded in a conventional argument’ seems to reflect the opinion that the algebra ‘speaks for itself, rendering the specific economic debate in the context of which it was formulated of scant importance. Against this, it can be argued that by lifting the explicitly mathematical passages from the Traité and considering them in isolation one can come to a limited understanding only of what Isnard was trying to demonstrate. At most it allows one to form a judgement about his formal achievement in using a system of simultaneous equations to illustrate the notion of market equilibrium. An appreciation of this formal achievement in itself is of course by no means meaningless. However, as is argued in section 2.1 (p. 24), this differs from a further understanding of how the engineer’s mathematical analyses are part of a larger economic argument. The observation that Isnard has been ignored by those students who would have been interested in his wider economic thought is based on the fact that even in the very best studies about the state of economic theory during the French Enlightenment, Isnard’s name is either missing or merely mentioned in passing without elaboration of his ideas. To give a few examples, the engineer hardly features in what are the best studies on physiocracy. In the multi-volume works of Weulersse, he is mentioned briefly only once (Weulersse 1984:30) and in the studies of Meek (1962) and Vaggi (1987a) not at all. There is also no mention of Isnard in the recent wide-ranging and excellent collection of papers on eighteenth-century economics by Groenewegen (2002). The only two exceptions of authors who provide somewhat lengthier discussions of Isnard’s economic ideas in the context of eighteenth-century economic theory are Spengler (1942) and Perrot (1983).7 It was thought that the most effective way to contribute to a change in the current state of knowledge about Isnard’s economic thought would be to present the whole of Book I of the Traité together with a selection of further sections (see Part B). Before investing time in reading these excerpts, the reader may want to know what their significance is in the larger picture of the history of economic thought. The following brief indications should suffice. In the first place, the belated influence of Isnard on Léon Walras is of course fascinating. Jaffé’s case to prove that this influence was considerable has been deemed over-enthusiastic in a number of details by Klotz (1994), but remains in substance uncontested. What needs to be noted, however, is that there may be a great difference between what Walras found of use in the Traité for his own purposes of constructing a general equilibrium model on the one hand, and a reading that attempts to discover the ‘authentic’ views of the engineer on the other Second, Isnard’s writings offer interesting new perspectives on the analytical weaknesses, but also the rich potential of physiocratic economics. As will be argued in section 2.1 (pp. 24–51), a more historical understanding of the economic theory of the

At the origins of mathematical economics

4

Traité can be gained by comparing it to the ideas of François Quesnay (1694–1774). Isnard was one of the most perceptive contemporary commentators on Quesnay’s economic thought. In part his ideas are an incisive critique of the physiocratic conceptions of productivity and distribution. At the same time however, the engineer retains the doctor’s fundamental conception of the economy as a single reproductive system capable of producing a social surplus. What he adds to the physiocratic system is chiefly a way of incorporating the role of relative prices in the process of reproduction and a keen awareness of the relation between the theories of value and distribution. Third, for this same reason Isnard’s contributions are also significant in the context of the history of classical political economy more generally. Quesnay’s role as a major figure in the formation of the classical tradition of economic theory is widely recognised (see e.g. Garagnani 1984; Blaug 1987:439; Vaggi 1987b: 875). If we consider the central problematic of the classical approach to be the production of a social surplus and its distribution then Isnard’s theory qualifies as a post-Quesnay variant within this tradition. As such he belongs to the generation of Adam Smith. The wellknown notion of Smith that the ‘annual produce’ of an economy ‘divides itself into two parts’, one ‘destined for the replacing of capital’ and the other for the payment of profit and rent equally derived from Quesnay’s analysis (Smith 1776, II: iii; see Groenewegen 1987:213). Interesting comparisons may be made between elements of Isnard’s theory and that of the immeasurably more famous Scotsman.8 For example, while both men reject Quesnay’s opinion that only agricultural labour is ‘productive’ and that rent is the only surplus income, Isnard’s alternative conception of the social surplus as a heterogeneous physical magnitude (‘masse réelle’) is quite different and indeed simpler than Smith’s.9 On the other hand, Smith’s conceptualisation of the income shares of ‘wages’, ‘profits’ and ‘rents’ is superior to that of the engineer (see p. 36). But what makes Isnard’s approach to the phenomena of reproduction, value and distribution most distinctively different is his avoidance of the hypothesis of a single determinant of value. Under the influence of Ricardo, the labour theory of value, intimated by Smith, came to play a central role in British classical political economy. Isnard’s writings, on the other hand, offer a glimpse of how the ‘surplus approach’ to value and distribution might have developed after Quesnay, without recourse to the labour theory of value. ‘Might have’, because the engineer’s influence on authors of the classical period was next to zero (see Chapter 3). In addition to the excerpts from the Traité a small selection from Isnard’s later writings is presented here too. While his reputation as an economic theorist is based almost exclusively on the content of three or four pages from his first book, the engineer continued to publish over a tumultuous twenty-year period a total of eleven further works. Most of these are pamphlets, but there is also a full-size book and a four-volume work. Altogether his published works add up to well over 3,000 octavo pages. At the same time, the secondary literature on Isnard’s writings other than the Traité is to the best of my knowledge almost non-existent.10 Not even a complete listing of his various publications has ever been made (I hope to have remedied this in the Appendix). It would go much too far to say that all of this material is of prime importance. Without wanting to discourage anybody from preparing a collected works, it may be noted that quite a lot of it does not even make remotely stimulating reading. Why then is it worth looking further than the Traité des richesses? First, Isnard revisits a number of

Introduction

5

his fundamental economic ideas in later texts, giving different formulations to them in response to authors not featuring in the Traité. For example, in the pamphlet Réponses of March 1789 and the article Du nouveau systême d’impôts of July 1791 aspects of his economic theory are compared not only to the ideas of the physiocrats, but also to those of Condorcet and Adam Smith. Second, the principal objective of these texts is to contribute to the debate of the early revolutionary years about the reform of the French tax system. As such they give a flavour of how ideas that must have seemed academic in the early 1780s, quite suddenly acquired a new urgency a decade later in the context of the possibility of real, sweeping reform in economic policy. Another example of this is the article Reflexions sur remission des assignats (1790), in which Isnard applies his ideas on money to judge the wisdom of the notorious monetary experiment of the Revolution. Even if Isnard’s ideas had negligible influence on the actual reforms that took place in these years, it is interesting to read his responses to the momentous institutional changes in France during the Revolution. Third, beyond the Traité there are to be found texts that do not deal with political economy per se, but which provide important additions to his social theory. Here the main work is the surprising Cathéchisme social (1784). If the Traité des richesses is Isnard’s Wealth of Nations then the Cathéchisme social is his Theory of Moral Sentiments. Though both books of the engineer are far less accomplished than the respective works of Adam Smith, he emerges from the excerpts presented here as a much more all-round social theorist than he has ever been given credit for. A short outline of the ways in which the ideas of the Cathéchisme complement the economics of the Traité is given in section 2.2. Finally, Isnard’s last publication Considerations theoriques has been included in full. It is an exercise in financial mathematics, which addresses the question, hotly debated at the time in France and Britain, of the beneficial effect of sinking funds for the reduction of state debt. The texts and translations are preceded by a somewhat lengthy introduction to Isnard’s writings, intended to provide the reader with the necessary background. Chapter 1 is a biography of Isnard. Chapter 2, as already indicated, attempts to show how his mathematical analyses of exchange and production form part of his wider social and economic theories. Chapter 3 is a short review of the curious history of the reception of Isnard’s work. Neither the introduction to the texts nor the selection of texts itself pretends to provide a full coverage of the material available. Rather, it is hoped that by making part of Isnard’s writings more accessible further study and a fuller appreciation is encouraged of the ideas of an author who, as one of his contemporaries put it, ‘[…] is often not noted amongst so many others who make much more noise’ (see Chapter 1, note 64).

Part A The economics of A.N.Isnard

An introduction

1 Life and career of Achilles Nicolas Isnard (1748–1803) Considering that Isnard never achieved fame, influence or high office, the detail that can still be salvaged about the man’s life and career two centuries after his death comes as a pleasant surprise. It is remarkable that until relatively recently hardly any biographical details were known about the engineer-economist. As Jaffé (1969:22) notes, ‘even the most canny of historical sleuths, Joseph Schumpeter’ had been unable to turn up even the simples vital data about Isnard. Jaffé states this with a certain glee, because he had come across the forgotten doctoral thesis of Louis Renevier (1909). This work contains what remains to the present day the only detailed biography of Isnard based on primary sources. Jaffé‘s short sketch of Isnard’s life (Jaffé 1969:22–4) is entirely based on Renevier, as are subsequent accounts (Hébert 1987; Klotz 1994:30–2). This is unfortunate because Renevier’s biography (1909:5–23), though relating many interesting details, is in a number of places imprecise, or plainly incorrect. What is more, Renevier relies entirely on a single source, the surviving correspondence between Isnard and his superiors in the corps of Pont et Chaussées presently in the Archives Rationales in Paris.1 What is related in this correspondence can be verified and supplemented by documents in two other archives, those of the École Rationale des Ponts et Chaussées in Marnela-Vallée and in the Archives Départementales du Rhône in Lyon. Since these sources appear to have escaped attention so far, it is judged useful to provide here, nearly one century after Renevier and two centuries after the engineer’s demise, a new and more critical sketch of the life and career of Achilles Nicolas Isnard.2 Unfortunately, the first biographical data one would want to know, Isnard’s date and place of birth, are uncertain. No birth certificate or similar document has been found, and therefore one has to rely on indirect evidence. Renevier (1909:5) states that our man was born in Paris in 1749 Very probably on 25 February’. No justification for the day and month are given and the fact that they are the same as the date on which Isnard died is curious to say the least. Moreover, Renevier seems to arrive at the year 1749 simply by subtracting the age at death, 54, from the year of death 1803.3 Of course, deduced in this manner Isnard’s birth date could be any time between 26 February 1748 and 25 February 1749. A separate piece of information suggests 1748 as Isnard’s most likely birth year: in the student register of the École royale des Ponts et Chaussées we read’ [o]n 9 December [1767] Mr. Achilles Nicolas Isnard, age 19, has entered the school of ponts et chaussées’.4 In combination with the first clue this limits the period during which Isnard might have been born to sometime between 26 February and 9 December 1748.5 The year of birth 1748 is confirmed on a fiche at the archives of Ponts et Chaussées but this source surprisingly also gives Carcassonne as Isnard’s birthplace.6 However, an unsuccessful attempt to confirm the latter claim,7 together with a clear statement in the death notice that Isnard was ‘a native of Paris’, seems to decide in favour of the French capital.

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Thus the best available evidence suggests that Isnard was born in Paris in 1748. Not much is known about his family background. I have not been able to trace the first names of either parent. However, a telling piece of information about Isnard’s father is that at the end of the 1760s he was ‘intendant of the duke de Chevreuse’.8 Marie-Charles-Louis d’Albert de Luynes, due de Chevreuse (1717–71) was made a governor of Paris by the king in 1757 after an illustrious military career. The function of intendant, or ‘general manager’, to such a high official is likely to have required academic qualifications and suggests at least sufficient wealth and social rank to obtain the necessary training. From this it may be conjectured that the Isnards were a relatively well-off bourgeois family. This social background is also consistent with the career of Achilles’ only known sibling, Jean Louis, who entered the legal profession, first as a lawyer and eventually became a judge. Achilles received all his education at Paris. For some years he studied mathematics, map drawing and fortification.9 It is likely that he also gained some initial practical experience as the apprentice of an engineer, as was a common practice for pupils prior to entry to the royal school of civil engineering (Petot 1958:149). When he was officially admitted to the school on 9 December 1767 he entered an institution that in recent years had started to acquire a Europe-wide reputation for its high levels of technical education (Petot 1958:144). Ponts et Chaussées, out of which grew the first of the prestigious grandes écoles, had for two decades been the principal instrument used by the French government to raise the level of civil engineering.10 The gradual introduction of an exacting curriculum, strict discipline and hierarchy, and a distinct esprit de corps was to a large measure the work of Jean-Rodolphe Perronet (1708–94), the paternalistic director of the school from its foundation in 1747 until his death. The organisation of the school was designed to favour the brightest and most hardworking students. There were three classes of between twenty to thirty students each, and every three months a ranking was made of all students on the basis of their merits. Progression up the ranking, and promotion from one class to the next, depended on the achievement of prizes in the regular essay competitions, practical experience gained during summers at engineering projects and satisfactory completion of optional courses. Only the students who had climbed to the highest places in the top class could hope to obtain an appointment as assistant engineer somewhere in the kingdom whenever a place in the service became available. There was no official limit to the length of stay at the school: around the time Isnard left the average was between seven and eight years, with a minimum stay of three and a maximum of twelve years (Petot 1958:152). That was the case for the students who actually graduated; most never made up the distinctly greasy pole: of the 387 students admitted between 1769 and 1788, nearly two-thirds, left without obtaining the much desired grade of assistant engineer. Within this competitive intellectual environment Isnard soon flourished. His academic progress can still be followed exactly in the quarterly États des Talens des Élèves du Bureau des Ponts & Chaussées.11 Starting in the second quarter of 1768 we find him as student number eighteen (out of thirty) in class three, studying besides compulsory subjects like geometry, map design, and architecture, the optional course in ‘application of algebra to geometry and mechanics’. After about a year, having spent the summer and autumn of 1769 at engineering projects in the generality of Tours, Isnard started making steady progress through the ranks. In the second quarter of 1770 he entered the second

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class and won a prize in the architecture competition. Later that year he was awarded a pension by the king for private study of architecture at the institute of Blondel, a special privilege reserved to four students at a time (Dartein 1906:53).12 When he returned to the main school, in the second quarter of 1772, he entered the first class where he was ranked eigtheenth (out of twenty-four). Soon after winning the first prize in that year’s architecture competition, his request to be employed at engineering works at a sea port was granted and he spent the summer and autumn working on the improvements of the port of Les Sables-d’Olonne on France’s central Atlantic coast. It seems to be the beginning of a career-long preference to work at the prestigious hydrological projects of Ponts et Chaussées, expressed many times in his letters of later years. A highly motivated Isnard returned to Paris in December 1772. In the following year he became one of the top-ranking students of the school. For these pupils it was not uncommon to teach fellow students. In the report of the first quarter of 1773 we read that Isnard has taken over the algebra classes from the absent professor Boncefin.13 While continuing teaching these classes in the second quarter, it is also noted that he teaches geometry, and at the end of the year it is further added that Isnard ‘teaches the class in differential and integral calculus’.14 From the fact that he was entrusted with the teaching of these various classes at the foremost technical school in France, we may safely conclude that he was by this time proficient in several branches of mathematics. Also from this period dates the first evidence of an acquaintance with the physiocrats. In the Traité des richesses (1781, I: xii) Isnard states that from his ‘earliest youth’ he had been interested in ‘politics, trade, and finance’ and for a young Frenchman with such interests it would have been hard to avoid the ideas of François Quesnay and his followers. By the second half of the 1760s this group of writers, known at the time as the Économistes, had organised themselves into an influential ‘school’ professing a single set of economic and social doctrines, which they promulgated in their own journals and debating clubs.15 One of the most active members was Pierre Samuel Dupont (1739– 1817), from 1768 editor of the Ephémérides du citoyen. It was with this prominent physiocrat that the young Isnard established friendly relations in the early 1770s. This can be inferred from a single letter, from Dupont to Isnard of 28 December 1773, which survives from what appears to have been a larger correspondence.16 In the letter Dupont discusses the principles of differential calculus in a manner that Isnard, who at the time was teaching this subject, would surely have recognised as rather inept.17 Perhaps it can be inferred from this contact that Isnard for some time associated himself with the circle of the Économistes. If so, he soon fell out with them. This may be read into Isnard’s, admittedly cryptic, remark that his early attempts at economic theorising were frustrated ‘[…] because I could not accept the obscure ideas communicated to me by the organ of the favoured [i.e., the physiocrats?] in exchange for the favours to which I aspired’. Therefore, he continues, ‘I gave up pretending with the aid of grace, and I decided to study’ (Isnard 1781, I: xii). Judging by Isnard’s detailed knowledge of the physiocratic literature, Quesnay’s social and economic theories provided the main incentive for this study. In the meantime Isnard’s quick progress up the student ranking at Ponts et Chaussées seemed to justify an imminent graduation. When in the third quarter of 1773, the ranking procedure was formalised by means of a point system, Isnard was given 131.5 points, the

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highest score of all students.18 Nevertheless, for reasons that are not entirely clear, he was made to wait until the beginning of 1775.19 Finally however, on the 1st of April of that year he was appointed assistant engineer in the generality of Besançon, with a residence at Arbois, a small provincial town near the Swiss border.20 Isnard was to stay at his first posting for ten years. The position of assistant engineer brought with it a steady income. According to common practice, after two years his annual salary was raised, from 1,200 to 1,500 francs.21 Financial security is likely to have influenced the serious young man’s decision to start a family at around this time. There can be little doubt that during his period at Arbois Isnard met his wife Catherine Françoise Pecauld22 and that not long after marrying they had their first child, FelixJeanne Cornelie.23 Settling into a tranquil family life as a devoted husband and father, Isnard must have found plenty of time and solitude to bring to fruition the comprehensive social theories of his two main works. The first of these, the two-volume Traité des richesses was published at the beginning of 1781 by François Grasset in Lausanne, Switzerland.24 The proximity of Arbois to Lausanne, the principal printing centre in the region, seems to be one reason why Isnard chose to have his work published across the border. The other reason was surely prudence: in the work Isnard severely criticised the then contrôleur-général, Jacques Necker (1732–1804).25 It would have been extremely unlikely for such a book to receive the required official, or even tacit, permission to be published in France. More than a century later Stanley Jevons would point out the historical coincidence that Walras would become rector of the Academy of Lausanne, a town ‘[…] already distinguished by the early work of Isnard’.26 François Grasset, a rather business-minded publisher,27 cannot be blamed for not having seen things quite that way. He appears not to have been very keen on publishing the lengthy and involved economic reflections of a provincial assistant engineer. It was probably for this reason that Isnard paid for the printing costs of the Traité himself.28 By publishing a book with outspoken political views Isnard did not only defy the censor but also disobeyed the official guideline that engineers in the king’s service should obtain special permission to express such views in print (Etner 1987:48). Isnard did not request this permission and may have hoped to be protected by the fact that the book was published anonymously. However, not long after the publication of the Traité he was revealed as the author resulting in a reprimanding letter from Perronet.29 It was neither the first nor the last time for the young engineer to be slapped on the wrist. In fact, in this period the young man started to develop problems with the unquestioning obedience demanded of engineers. A revealing episode occurred on 22 May 1781 when Isnard failed to report corvoyeurs who staged a walk out at the works he was overseeing. One suspects he sympathised with the men’s protest since he considered the corvee as an unjust and oppressing institution.30 When the men returned to the works after three days, Isnard decided that it was ‘inutile d’en faire une affaire’. Word got out, however, to his superior Philippe Bertrand that there had been ‘quite a scene’ (un esclandre considerable) at Isnard’s works. A full report was demanded, which Isnard duly supplied by the 19th of June. On the basis of this Bertrand decided that Isnard could not be blamed for the disturbance and in a letter to Perronet he took the responsibility for any shortcomings in the actions of his subordinate.31 The next year however Bertrand expressed his dissatisfaction with Isnard, complaining to the head of Ponts et Chaussées about his

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subordinate’s slowness in drawing up a plan for a cascading aqueduct.32 Again Isnard received a reprimand this time telling him to be ‘more vigilant in the future’.33 The perceived neglect of his duties may well have had something to do with his continuing writing activities. Around this time Isnard was setting out his moral philosophy in the Cathéchisme social, which was ready for press in 1783. For this second theoretical work, which refrains from discussing any political or economic reforms, Isnard sought and obtained official permission from the censor,34 and the work was published by Guillot in Paris in March 1784.35 The somewhat placid theory of sociability presented in the Cathéc