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MERICAN UNIVERSITY STUDIES
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Perceptual System A Philosophical and Psychological Perspective Aaron Ben-Ze'ev
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The Perceptual System
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American University Studies
Series V Philosophy Vol. 138
PETER LANG New York • San Francisco • Bern • Baltimore Frankfurt am Main • Berlin • Wien • Paris
Aaron Ben-Ze'ev
The Perceptual System A Philosophical and Psychological Perspective
PETERLANG New York • San Francisco • Bern • Baltimore Frankfurt am Main • Berlin • Wien • Paris
Library of Congress Cataloging-in-Publication Data Ben-Ze'ev, Aharon. The perceptual system: a philosophical and psychological perspective / Aaron Ben-Ze'ev. p. cm. — (American university studies. Series V, Philosophy; vol. 138) Indudes bibliographical references and index. 1. Perception (Philosophy) 2. Perception. I. Title. II. Series. B828.45.B46 1993 12V.3—dc20 92-6211 ISBN 0-8204-1872-2 CIP ISSN 0739-6392
Die Deutsche Bibliothek-CIP-Einheitsaufnahme
Ben-Ze'ev, Aharon: and psychological perspective The perceptual system: ca tphilosophical ” pic York; York- Berlin; Rprlin- Bern; Rprrr Frankfurt/M.; Frankfnrt/M.i Paris; Paris: / Aaron Ben-Ze'ev.—New Wien: Lang, 1993 (American university studies: Ser. 5, Philosophy; Vol. 138) ISBN 0-8204-1872-2 NE: American university studies/05
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© Peter Lang Publishing, Inc., New York 1993 All rights reserved. Reprint or reproduction, even partially, in all forms such as microfilm xerography, microfiche, microcard, offset strictly prohibited. Printed in the United States of America.
TABLE OF CONTENTS
Preface Chapter 1: The Emergence of the Perceiver (1.1) Naive Realism (1.2) The Emergence of Perceptual Subjectivism (1.3) The Basic Assumptions of Perceptual Dualism (1.4) Different Versions of Perceptual Dualism (1.5) Criticism of Perceptual Dualism
Chapter 2: Mental States (2.1) States rather than Entities (2.2) Stratification rather than Causation (2.3) More about Stratification (2.4) Continuity rather than Dichotomy (2.5) The Basic Mental Dimensions: Feeling and Intentionality
Chapter 3: Perceptual States (3.1) Initial Characterizations (3.2) The Direct and Meaningful Nature of Perception (3.3) The Intentional and Feeling Dimensions in Perceptual Experiences (3.4) Perceptual Knowledge (3.5) The Ontological Status of the Perceptual Environment
Chapter 4: The Cognitive Paradigm of Perception (4.1) The Inferential Paradigm (4.2) Criticism of the Inferential Paradigm (4.3) The Constitutive Features: Schemas and Discriminations (4.4) Development and Organization of Schemas (4.5) Some Empirical Considerations (4.6) The Cognitive System in Perception and Thinking
Chapter 5: Perceptual Mistakes
vii 1 2 4 11 16
22 31 31 35 41 48
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76 81 89
103 103 109 117 126 133 140
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(5.1) The Direct and Indirect Approaches 145 r 'ix 'T'l_xt_______ i ____ 1’x'____________ !__ r_ — * (5.2) The Normal-Conditions Criterion for Perceptual Truth 149 157 (5.3) Do Perceptual Illusions Have Positive Features?
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Chapter 6: Implications for Other Mental States (6.1) Memory (6.2) Consciousness (6.3) Unconsciousness
161 161 173 177
Notes
185
Bibliography
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Index
213
PREFACE At first glance sense perception seems to pose few problems, since it appears to involve simply an awareness of independently existing objects. Although there is much truth in this naive view, which is close to the common-sense attitude toward perception, it has raised many conceptual difficulties that have exercised the minds of philosophers throughout history. In my own consideration of the subject I attempt to retain some of the basic common-sense assumptions about perception, while modifying them in a way that enables us to resolve various philosophical objections. But why should we trouble ourselves with all of these difficulties if the common-sense view is basically correct? Although my final position is undoubtedly similar to this view in some respects, the two views are not identical: they presuppose different conceptual frameworks. In Chapter 1, 1 begin by considering the view of naive perceptual realism, according to which perceptual qualities are assumed to be unaffected by and independent of the perceiver. I point out that such an attitude cannot explain many perceptual phenomena, particularly those which clearly express the agent’s role in perception. I then go on to consider a widely held approach in which perceptual qualities are treated as the properties of the perceiver rather than of external objects: we perceive mental entities which are merely the signs of external objects. This approach, which is called “perceptual dualism,” assumes that there arc two perceptual stages: sensation, which is a contentless stage that is devoid of active mental contributions, and perception, which is a contentful stage and is laden with mental contributions. Perceptual dualism, which arose from the failure of earlier forms of realism to explain all perceptual phenomena, does not undertake to modify realism but adopts a position that is opposite to it. I argue that this approach docs not offer an adequate explanation of perception. However, although the explanatory framework I propose in subsequent chapters is closer to the realist approach, it docs include some of the elements of perceptual dualism.
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Chapter 2 opens with a presentation of my own attitude to mental states in general. This approach involves three basic assumptions: (a) the mind consists of dispositional and actualized states and not of internal isolated entities; (b) physiological and mental states are not actually separate but belong to two different levels of description — the relation between them is one of stratification rather than of causality; and (c) mental and physical states emerge along a continuum that ranges from simple to more complex states. By treating mental properties as natural properties of the organism, I avoid a number of traditional problems concerning the mind-body gap. The last section of the chapter is devoted to feeling and intentionality, which 1 consider to be the basic mental
dimensions. In Chapter 3, I characterize perception in a different way from the prevailing view. I propose that perception, or rather perceiving, should be conceived as an intentional state of direct awareness of the environment, not as consisting of inner subjective entities, state of direct awareness of the environment. Perceiving is not a separate entity located in one’s head but an ongoing experience, which at any given moment is complete and also happening. I suggest that we do not encounter meaningless sensory data which are then converted into meaningful perceptions, but that we encounter a meaningful environment. This environment is on a different level of description from that of the physical world, and its existence presupposes the existence of a percciver. In Chapter 4, I examine the cognitive paradigm for explaining perception. In the prevailing inferential (computational) paradigm, perception is conceived as the product of prior and ordinarily unconscious inferences or computations. After showing this paradigm to be inadequate, I offer another model to explain the development of the perceptual realm and the cognitive activity pertaining to it. In this paradigm the cognitive structures (“schemas”) as well as the cognitive activities (for example, discrimination and discernment) are constitutive. As is the case of the other personal characteristics of the agent, cognitive features are not added as a consequence of preparatory processes but are expressed in perceptual schemas that are constantly participating in the ongoing activity of perception. Chapter 5 is devoted to the issue of perceptual mistakes, for which no adequate explanation is offered by either the direct or indirect approach to perception. I therefore present an alternative view, already adopted by Aristotle, that perception, as it occurs under normal conditions' 'S aS thcu crritcrion f°>- perceptual truth. These normal percenrion Xr S\ral^tfo^d and natural conditions in which here a context dp ens lc^y taJ'cs place in everyday life. Normality is relevan^^VfcwothT/XmdlX*1 my approach t0 Pcrception is
and unconsciousness ti,p k ■ StatCS’ namcly, memory, consciousness onsemusness. The basic assumptions of my view of perception
Preface
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arc shown to be basically sound when applied to other mental states as well.
ACKNOWLEDGEMENTS I began to work on the issue of perception in my Ph. D. dissertation Perception as a Cognitive System (University of Chicago 1981) whose adviser was Stephen Toulmin. Michael Strauss, who was my adviser earlier in my studies and subsequently became a colleague, is together with Stephen Toulmin responsible for shaping my view of perception and other fundamental issues in philosophy. Having completed the dissertation, I continued work on perception and other issues in the philosophy of mind. At that time I published several articles which have served as a basis for the present book. The passages from these articles I use have been completely revised while writing the book. 1 wish to extend my thanks for the permission to use materials from the following articles. "J.J. Gibson and the Ecological Approach to Perception,“ Studies in History and Philosophy of Science, 12 (1981), 107-139. "Toward a Different Approach to Perception," International Philosophical Quarterly, 23 (1983), 45-64. “The Passivity Assumption of the Sensation-Perception Distinction," British Journal for the Philosophy of Science, 35 (1984), 327-343. “What is a Perceptual Mistake?," Journal of Mind and Behavior, 5 (1984), 261-278. “The Dualistic Approach to Perception," Man and World, 17 (1984), 3-18 (with Michael Strauss). “The Kantian Revolution in Perception," Journal for the Theory of Social Behaviour, 14 (1984), 69-84 “Two Concepts of the Given," Dialogos, 19 (1984), 159-164. “Making Mental Properties More Natural," The Monist, 69 (1986),434-446. “Two Approaches to Memory," Philosophical Investigations, 9 (1986), 288-301. “A Critique of the Inferential Paradigm in Perception," Journal for the Theory of Social Behaviour, 17 (1987), 243-263. “The Schema Paradigm in Perception," Journal of Mind and Behavior, 9 (1988), 487-513. “Can Nonpure Perception be Direct?" Philosophical Quarterly, 38 (1988), 315-325. “The Relational Nature of Cognition," International Studies in Philosophy, 21 (1989), 1-12. “Explaining the Subject-Object Relation in Perception," Social Research 56 (1989), 511-543. “Conscious and Unconscious States," Philosophical Studies, 32 (Ireland), (1990), 44-62. “Cognitive Development: Two Paradigms," in H. G. Geissler, S. W. Link, and J. T. Townsend (cds.) Cognition, Information Processing and Psychophysics: Basic Issues (Hillsdale: Erlbaum, 1992), 67-90.
CHAPTER 1: THE EMERGENCE OF THE PERCEIVER For common sense, perception involves no particular difficulties: it is the simple awareness of objects and events in our environment. From a phenomenological viewpoint the agent indeed perceives objects directly with no particular cognitive activity on his part. This seemingly unproblematic character is expressed in the philosophical view of naive realism, which denies that the agent has any significant cognitive role in perception and assumes that perceptual qualities are unaffected by and independent of the agent. There are, however, phenomena such as perceptual illusions and perceptual relativity which are incompatible with naive realism since they indicate an active cognitive role on the part of the agent in determining perceptual content. Moreover, analyzing the causal processes involved in perception reveals that very complex physiological processes take place in the perceiver’s head. Accordingly, explaining the agent's role in perception becomes a difficult task. In this chapter I discuss two major approaches toward such an explanation: naive realism, which denies the agent any role in perception, and perceptual subjectivism, in which perceptual qualities are laden with the agent’s contributions and arc merely mental representations of external objects. I focus on the second approach, which is more prevalent and which involves consideration of the central problems occupying modem perceptual theories. The discussion is not intended to exhaust the various approaches to perception but to present two major trends, for which I suggest an alternative. (Unless otherwise indicated, I use the term “perception” to mean "sense perception.”)
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(1.1) Naive Realism Sense perception reveals a richly meaningful environment: green mm’ Tk??8 buhlldul8\thc clamor of a crowdthe touch of love, a flight of birds, a happy child, attitudes o care ami concern, and so on. The question is if, and how far, the agent involved hi the creation of that environment. I his is a specific problem associated with the more general problem of the subject-object relation Regarded naively, perception would seem to be unproblematic, involving merely a passive awareness of the environment in which we live Difficulties arise once we reahze that the agent is not passive in perception. ., , When merely the physical structure of the pcrccivcr is considered the relation between the pcrccivcr and other physical entities in the world poses no special conceptual problems, because they all belong to the physical level of dcscnption. The difficulty arises when we realize that complex organisms have developed cognitive capacities by which they know something about their surroundings. These capacities may be exercised with varying degrees of success and from a variety of perspectives, which implies that the agent's cognitive system may influence cognitive content. If indeed such an influence is to be found, one can pursue the consequent ontological implications and question the possibility of an independent perceptual environment. One way of disposing of the difficulties in the subject-object relation in perception is to deny the existence of one side of the problematic relation, doing away with either the subject or the object. Reductions of this sort take the form of naive perceptual realism and extreme perceptual subjectivism. Naive perceptual realism assumes that the perceptual environment exists independently of the perceiver and is unaffected by the perceptual process. Realism is an ontological attitude assuming the existence of entities that are independent of the agent; and “naive” is an cpistemic term referring to the cognitive passivity of the perceiver. In this view, any influence of personal characteristics (such as memory, belief, desire, motivation, emotion, expectations, etc.) upon perceptual content is taken to be an interference with valid perception. The act of perceiving docs not change the properties of the perceptual environment but merely reveals them as they exist independently and outside of the perceiver. There is an identity here between perceptual content and the properties of the environment. Naive perceptual realism has its own charm. It is the position from which we start before reflecting on the nature of perceptual experience. It is also close to common sense. The latter, like the former, assumes the independent existence of the perceptual environment, and a certain passivity on the part of the perceiver in the perceptual process. Realism in its various degrees of naivete was the view that prevailed in ancient thinking, in which the agent’s role in perception (and cognition in general) was not a crucial factor in the explanation of perception. For example, mythical thinking does not involve the appearance-reality distinction and the subjective-objective distinction. The perceiver is an
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integral clement of the environment. Primitive people do not ascribe to themselves a unique cognitive place in the environment, so the problematic subject-object relation is not yet apparent. There is also evidence that very young children possess no understanding of the appearance-reality distinction. (However, they actively respond to the pretend-real distinction, which already entails an active role on the part of the subject, at an earlier stage in their lives.)' At first sight, naive perceptual realism seems to be an attractive view. The question is if it can adequately explain all the problems concerning the agent’s role in perception. A major obstacle in this connection is the naive attitude of this approach. Phenomena such as illusions and perceptual relativity indicate that, contrary to this attitude, the pcrccivcr docs influence perceptual content. A perceptual illusion, or falsity in general, is usually explained by referring to mistaken contributions of the agent. Falsity is not an attribute of the world, but of the cognitive claims the agent makes about the world. The tree itself is neither true nor false; only claims about the tree may be true or false. In a view that assumes pure receptivity and denies any contribution of the agent in the perceptual process illusions are hard to explain. The very nature of illusions is their difference from, and not their identity with, the nonillusory properties of objects; and this difference would appear to be a consequence of the agent’s cognitive system. The same may be said of perceptual relativity, namely, cases in which different people, or the same person in different situations, perceive the same object differently. Naive realism is hard put to explain phenomena such as these since it takes no account of the active role of the agent in determining perceptual content.2 Accordingly, an extreme form of naive perceptual realism is very rare (if it exists at all) among critical thinkers. As mentioned above, common sense is quite close to naive realism. Nevertheless, common sense does admit the existence of illusions, perceptual relativity, and other phenomena that indicate the influence of the pcrccivcr upon perceptual content. By doing so common sense gives the appearance of being inconsistent. But common sense does not (and need not) offer a comprehensive theoretical position, only a collection of widely accepted contentions that arc not always well connected. It is the task of science and philosophy to formulate a coherent and comprehensive view. Ancient Greek philosophers formulated positions that were more sophisticated than naive realism, but perceptual realism was nevertheless the prevailing view among them. Although the pcrceivcr's role was often acknowledged, perceptual qualities were generally regarded as having an independent existence. Aristotle offers a highly developed theory of perception which accommodates distorting contributions by the pcrccivcr. Thus, when we are ill or injured our perceptual system may not function adequately, causing our perception to be false or distorted. Or in intense emotional states such as fear or love, the senses are easily deceived because pcrccivers project their own emotions onto the environment. Slight resemblances may deceive cowards into thinking that
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they see their enemy, or lovers into believing that they sec their beloved. The more intense the emotional state, the more readily do perceptual distortions occur. Aristotle also acknowledges the existence of perceptual relativity. Generally, Aristotle assumes that under normal conditions we perceive the real properties of the objects.3 When the perceptual system is functioning properly, it should be able to fulfil its purpose successfully and to acquire undistorted perceptual knowledge. In Aristotle’s view we already find a separation between the perceiver and the perceptual environment, but this is not treated as an unbridgeable gap. Under normal conditions this separation is overcome. The perceiver does not merely know the perceptual environment adequately, but he and it are actually assimilated into one another in the activity of perception. The activities of the perceptual object and of the senses arc two aspects of the same thing, just as the uphill and the downhill paths are.4 I note here that my view is similar in some respects to Aristotle’s, and I will therefore postpone a further discussion of his view of perception until I come to deal with my own position.
(1.2) The Emergence of Perceptual Subjectivism
The agent’s role in perception became a central issue in the philosophy of perception when the problematic nature of that role was realized. Such a realization emerged around the seventeenth century, when the mind’s relationship to nonmental entities came to be regarded as problematic. This relationship consists of two different relations: the relation of the mind to the physical system in which it is located, and the relation between the mind and the entities to which it refers. The first relation is ontological and is expressed in terms of the mind-body problem, whereas the second relation is epistemological and is expressed in terms of the subject-object problem. In the Cartesian framework the two types of relation are very problematic because unbridgeable gaps arc assumed between the two variables that constitute each relation. The mind and the body are assumed to be two isolated ontological substances. Likewise an epistemological gap between the information presented to the internal mind (subject) and the properties of external objects is assumed to exist. When Descartes replaced the broader ancient notion of “soul” with the more circumscribed notion of "mind," he not only limited the scope of the soul but also separated it from the body and gave it substantive s*atus- The mind in the Cartesian approach is clearly distinguished from he body and any relation between them is hard to conceptualize. I cannot discuss here in detail the reasons for the emergence in modern P osophy of the ontological mind-body gap, but it seems that a major WaS * le Pass'vc characterization of matter by modem science. In SnnntI^me'VOr^ (,?hy.s*.ca^ ma,*er can never put itself in motion, absent frn°USti?r activities, so typical of the mental realm, arc aosent from the mechanistic, inert world of the new natural science. This
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strict conception of matter clearly separates matter from mind, and there is no longer a place for active mental operations in the inert material world of physics. Also, modem religious conceptions of the soul and of the central place of its inner life have played a part in creating the mind-body gap.5 'I'hc passivity of matter is clearly indicated in Descartes' first law of nature: "Each and every thing, in so far as it can, always continues in the same state; and thus what is once in motion always continues to move." Each thing “always remains in the same state, as far as it can, and never changes except as a result of external causes. Thus, if a particular piece of matter is square, we can be sure without more ado that it will remain square for ever, unless something coming from outside changes its shape.” God, having created the world, “now preserves all this matter in the same way, and by the same process by which he originally created it.” The passivity of matter in Descartes' sense is inertness, an object’s inability to initiate changes to its own states; the relevant sense of activity in a mind is spontaneity or the ability to initiate changes of state. In Descartes' view the mind is active and can originate its own activities. This is the case of our volitions, which proceed “directly from our soul” and seem to “depend on it alone.” Hence, “the will is by its nature so free that it can never be constrained.”6 The dichotomy between the activity of the mind and the passivity of matter is quite evident in this influential view. Although I believe that the dichotomy between passive matter and active mind was an important reason for the emergence of the modem mind-body dualism, I do not claim that (a) there is a necessary logical entailment between the two positions, and (b) that all (or even most) philosophers based their dualistic position on this dichotomy. Regarding (a), one can deny the spontaneity of mind or the inertness of material things and still hold a mind-body dualism, basing it on some other genuine or alleged incompatibility between mental and physical properties. As for (b), Descartes, for example, docs not argue for his mind-body dualism on the basis of the dichotomy between passive matter and active mind; in the Sixth Meditation he appeals to the essential divisibility of extension and the essential indivisibility of thoughts as the reason for his dualism. Despite these reservations, I believe that the emergence of the passive characterization of matter, and hence the dichotomy between passive matter and active mind, is an important conceptual shift facilitating the emergence of the mind-body dualism. Historically, the two positions have been advocated by many modern philosophers. The ontological mind-matter (or mental-physical) gap is thus expressed in the assumption that the mind (a) is composed of different "stuff' from the material one, and (b) exists as a separate substance. Such an ontological gap is not typical of ancient philosophy. Concerning the first feature of the gap (i.e., the different ontological stuff), Aristotle, for example, assumed there to be a kind of continuity, rather than a gap, between psychical and physical processes; psychical processes arc to be
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found not only in humans but also in animals and plants: "The principle found in plants is also a kind of soul.”7 In this way the psychical-physical gap is diminished, since the distance between plants and inorganic bodies is much narrower than that between the rational conscious mind and inorganic bodies. Unlike modem views, in Aristotle's view of the soul the main distinction is not between a rational conscious mind and an inanimate body but between living and nonliving substances. The gap in the latter distinction is narrower. Concerning the second feature of the ontological gap (i.e., the existence of the mind as a separate substance), Aristotle assumes the mind to be the form of a living body, not a separate entity within it. Also for Plato, who assumed different kinds of existence for different entities, the modem mental-physical distinction did not play a crucial role. Ancient thinkers avoided postulating a clear-cut dichotomy between the human mind and other things. Toulmin claims that while Greek scientists in classical antiquity did not separate the known object from the knowing subject, the scientists of the seventeenth century did. In ancient times the natural cosmos had been thought of as a vast, ensouled organic being, whereas in the new natural philosophy, which emerged around the seventeenth century, it was depicted as a single grand mechanism, a great clock or train of gears. The assumed ontological separation between the mental substance and the physical body, and hence the difficulties in explaining their relation, leads to difficulties in explaining the epistemological subject-object relation. The ontological separation is associated with two other prevalent positions: that the mind is internal and that the mind is representational in nature. The internal nature of mind (i.e., that the mind is inside the brain) is assumed to be both a result of the difficulties of locating the mind in the external physical world (though of course the brain is a physical entity too), and a consequence of the phenomenological impression that most of our mental activities are internal. Another explanation for the supposed internal nature of the mind is that the basic task of the physical sciences, as conceived since the seventeenth century, is to show how the evident macroscopic properties of material things manifest the interactions between their hidden submicroscopic constituents, such as atoms and electrons. This assumption has been applied to psychology, which is conceived of as being concerned with breaking overt human behavior into atomistic entities and processes that exist inside the mind.9 It has been claimed that ust as physicists cannot see the atoms they talk about, psychologists can t watch the processes they try to examine. We only 'know' such things through their effects.”10 The view that the mind is located internally is often associated with reht;AP„r?entatlOn^ view “ which thc mind is assumed to have no direct mental 1° matcna^ objccts. but to refer to these objects through internal head ., prc5enJatlons' Since physical objects cannot enter thc agent’s separation brtm myst C0I]taan bitemal signs of these objects; thc epistemological reh f C nUfd p.llys’ca^ w°dd seems to require thc ‘ogteal relation of representat.on. Thc representational view of
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mind can be maintained, however, without assuming the intcmality of mind. The latter position is hard to defend, whereas the former is a natural consequence of assuming an unbridgeable separation between the mental system and the physical world. The conception of the mind as internal and representational in nature is clearly expressed by Locke, according to whom the senses arc "the windows by which light is let into this dark room (viz. the understanding). For, me the understanding is not much unlike a closet wholly shut from light, with only some little openings left, to let in external visible resemblances, or ideas of things without." Perceptions and thoughts arc internal mental entities: man’s thoughts "arc all within his own breast, invisible and hidden from others.”11 The internal and representational nature of the mind gives rise to an epistemological gap which is expressed in the difference between the impoverished sensory signs presented to the mind and the various properties of external objects. In this view the initial data (sensations) given to the mind are mental signs of physical objects; a sign “need not be similar in any way to that of which it is a sign.”12 Accordingly, it has been argued that perceptions are constructed from fleeting fragmentary scraps of data that are signaled by the senses. Normal everyday perceptions, in this view, are not part of the world of external objects; hence, all perceptions are essentially fictions.13 Indeed, since the seventeenth century science has conceived its subject matter as existing behind sensory qualities. These subjective qualities are merely signs of the objective physical world. “The sense perceptions have been definitely eliminated from the physical acoustics, optics and heat. The physical definitions of sound, color, and temperature are today in no way associated with the immediate perception of the respective senses."14 The epistemological gap gives rise to severe difficulties of the kind illustrated in Ryle's graphic portrayal of it: “There is immured in a windowless cell a prisoner, who has lived there in solitary confinement since birth. All that comes to him from the outside world is flickers of light thrown upon his cell-walls and tappings heard through the stones; yet from these observed flashes and tappings he becomes, or seems to become, apprised of unobserved football-matches, flower-gardens and eclipses of the sun."15 Not only the ontological gap, but the epistemological gap too was uncommon in ancient thinking. The discovery that three-dimensional properties of objects are not represented in the sense organ in a direct or simple manner was not trivial, and it was believed, for example, that the stimulus to vision shares the properties of the seen object.16 No wonder, then, that "one question that has persistently plagued modem philosophy was never explicitly discussed by Aristotle, namely how and in what manner we perceive or come to be aware of the concrete, physical objects to which sense-qualities belong. Aristotle, it seems, never considered this an important philosophical question; he nowhere discusses it directly. No Greek, for that matter, ever addressed himself to this question.”17 It can arise only after the postulation of the ontological
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and epistemological gaps between mental appearances and physical objects. I do not claim that no distinction was made in Greek philosophy between what appears to us and other entities. The pre-Socratic philosophers had already endeavored to point out the substance behind all appearances. However these appearances were not regarded as mental signs; so these ontological and epistemological gaps were absent in ancient philosophy, or at least they were not sharply drawn. Modem philosophy cannot be satisfied with Aristotle’s contention that under normal conditions an organism must have reliable perceptual knowledge of its environment. Every modem theory of perception begins by questioning if such knowledge is at all possible^ and by searching for the foundations of perceptual knowledge. Because of the epistemological gap between the starting point of cognitive activities and the objective world which the final cognitive products are supposed to depict, this starting point has assumed crucial epistemological importance. If there is any hope at all of linking the mind to the objective world, it has to be sought in this starting point of pure sensation. Accordingly, the notion of a sensory given has become central: “If there be no datum given to the mind, then knowledge must be contentless and arbitrary; there would be nothing which it must be true to.” 8 The emergence of these ontological and epistemological gaps required a conceptual framework which somehow bridged these gaps. The most prevalent framework of this type is the view which we may term “perceptual dualism.” This postulates a distinction between two perceptual stages: a contentless, meaningless stage (sensation, which is devoid of active mental contributions) and a contentful, meaningful stage (perception, which is laden with such contributions). Perceptual dualism assumes that sensation is a passive reception of sensory input and that perception includes the active cognitive contributions of the agent. Whereas sensations are the inevitable results, or the immediate correlates, of physical states, perceptions are derived from sensations through supplementary cognitive activities of the agent. The distinction between sensation and perception is one way of bridging the ontological gap between the physical and mental realms. Although sensations are determined by physical events, they already exhibit some primitive mental features which do not require the active and complex operations that are typical of the mind, and may therefore be regarded as mediators between the physical and the mental realms. The role of sensation as an intermediate stage or “boundary between the mental and the physical” is evident in the position propounded by “s.s,eU:(, Sensations are what is common to the mental and physical “thn S’u, *;y,may be defined as the intersection of mind and matter"-, and ■sen Sfilhnac‘ bia9V" Physlcal “uses and mental effects we should define as absent in thot • 15 n;-Und t0 assume that the mental features which are
lh“*
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then sensation would have to be a typical mental stage and not an intermediate stage between the mental and the physical realms. I'hc intermediate ontological position of sensation is also connected with the causal thcop' of perception. This assumes a unidirectional causal chain, beginning with objective physical objects and ending with the subjective percepts in our heads: "Percepts are in our heads, for they come at the end of a causal chain of physical events leading, spatially, from the object to the brain of the percipient.”20 In this view perception involves an inference from the effect (sensation) to the cause (the stimulus source). An underlying principle in causal theories is that the effect cannot be greater than its cause. That is, there arc no properties of the effect which were not somehow present in the cause as well, otherwise something would be produced out of nothing. This principle as well as other considerations give rise to the question of how mental properties can be the effects of physical causes. Although Wundt conceives sensation as being the direct effect of physical and physiological stimuli, he nevertheless admits that “it is impossible to explain the character of sensations from the character of physical and physiological stimuli. Stimuli and sensations cannot be compared with one another at all." an.' 21 Regardless of the solution to this problem, the difficulty is less severe when the effect of the physical state is a very primitive mental stage, devoid of complex active mental contributions. In some versions of perceptual dualism the relationship between the last physical event in the causal sequence and mental sensation is not that of causality but of correlation. This suggestion, which stems from the conceptual difficulties in explaining a causal relation between physical and mental states, does not change perceptual dualism in any fundamental way, and here too sensation plays an intermediate role in the mental-physical gap. In respect of the epistemological gap the role of pure sensation is readily apparent. Sensations arc created by physical processes and this gives them some objective status: they arc not influenced by personal characteristics, and they cannot be false because physical states cannot be false. Accordingly, sensations arc governed by an objective regularity which can be revealed by objective research. The purity of sensations, and hence the nonarbitrary manner of their creation, is the cpistcmic guarantee of perceptual dualism for exposing the objective content behind them. This consideration would seem to be expressed by Helmholtz, when he observes that “even if in their qualities our sensations arc only signs whose specific nature depends completely upon our makeup or organization, they are not to be discarded as empty appearances. They arc still signs of something — something existing or something taking place — and given them we can determine the laws of these objects or these events. And that is something of the greatest importance.”22 In response to this claim one may doubt the existence of external objects and thus create further difficulties for perceptual dualism. This is indeed a genuine possibility which was assumed by various philosophers. However, once one adopts the realistic (and
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The Perceptual System
conunonscnsical) assumption concerning the existence of external . jects, the epistemological importance of an unmediated sensory stage ls evident (as illustrated in Helmholtz’s claim). In this contcct a distinction should be made between two different ypes of objectivity: objectivity stemming from the objective causal Process by which a mental state is created', and objectivity which lridicatcs that the content of the mental state adequately reflects the objective reality, namely, the reality which is independent of the mind. Sensation is objective in the first sense, whereas perception expresses the Irrst step toward objectivity in the second sense. Perceptual dualism assumes the first kind of objectivity in the hope that scientific research Can achieve the second type of objectivity by first going beyond subjective sensory content, and then going beyond perceptual content. The second type of objectivity seems to be the consequence of an rucrease in the (subjective) cognitive activities of the agent. I herefore, scientific theories, which involve cognitive activities beyond the agent s cognitive activities in perception, arc more objective than perception in the second sense (but not in the first). However, this does not suggest the existence of a mental stage, such as sensation, which is fully objective in the first sense. In short, the postulation of pure sensation, and with it the dualistic approach to perception, primarily derives from the attempt to find an intermediate stage that would close the ontological and epistemological gaps in the relation between the mind and nonmental entities. Sensation is a primitive mental stage in which no complex mental features are involved. Since sensation has physical causes and mental effects, it may be regarded as occupying the boundary between the mental and the physical realms. The absence of personal contributions in the creation of sensation makes it possible for dualists to claim that sensation is an objective starting point for the cognitive process, thereby offering an opportunity to the mind to overcome the epistemological gap between the impoverished information that is given to it and the properties of the external objects. Once the ontological and epistemological gaps between the mind and nonmental entities were postulated, naive perceptual realism could not remain an adequate philosophical framework. An illustration of the difficulties facing this view can be found in what is known as the “argument from illusion": 1) In illusions one does not directly perceive the object’s properties but something else; 2) what one directly perceives in illusions are internal mental entities; 3) the same system that deals with illusions also deals with veridical perceptions; 4) in veridical perceptions, too, one directly perceives only internal mental entities; 5) the existence of all qualities that are directly perceived depends on the existence of a perceiver.
The Emergence of the Percciver
II
Without entering into the details of this traditional argument, its implications arc clear. The cases that are problematic for naive realism furnish grounds for the opposite approach, namely, to deny the identity between perceptual qualities and properties of the object, and to assert the constructive nature of perception. If this is so, the agent may not be directly aware of the environment, a conclusion which in turn introduces ontological uncertainty. I;or if we arc directly aware of internal entities and not of external objects, then the very existence of these external objects is in doubt. The argument from illusion (as well as other related considerations) introduces at least three separate issues in the discussion of the subject-object relation in perception: 1) The epistcmic (cognitive) role of the percciver, or the question of if perception is constructive. 2) The direct or indirect nature of perception, or the question of if perception is representational. 3) The ontological role of the percciver, or the question of if the perceptual environment is subject-dependent. It can be noticed that once we admit the perceiver's active role, a host of difficulties arises. Dealing with these issues (and their ramifications) is the story of the critical thinking about perception. In ancient philosophy, where the perceiver’s role was not a crucial factor in the explanation of perception, not yet recognized, the most prevalent combination of the above delated (though distinct) issues consisted in a realist position that more or less denied the constructive, representational and dependent nature of perception. Comprehensive discussions of these issues are more common later on. It seems that only in modem philosophy has a subjective approach prevailed, so that all the above possibilities have been affirmed (at least to a certain extent). In the end I will propose a view that differs from the preceding two, and will argue that perception is constructive, direct, and in a certain sense subject-dependent. But before presenting my case, I examine in more detail perceptual subjectivism, which emphasizes the agent’s role in perception.
(1.3) The Basic Assumptions of Perceptual Dualism
Naive realism does not require a complex conceptual framework. It merely assumes that perception consists of direct awareness of properties that exist independently of the percciver. The assumption of the agent’s passivity, and of the identity between perceptual content and the objects’ properties, makes any complex perceptual system entirely superfluous. Admitting the presence of the ontological and epistemological gaps between the mind and nonmental entities requires a more complex framework than that presupposed by naive realism. These gaps compel a consideration of the above three issues: (a) the agent’s contributions to perceptual content; (b) the representational
12
The Perceptual System
nature of perception; and (c) the ontological status of the perceptual environment. There have been many philosophical views which attempt to overcome the difficulties surrounding the mind’s ontological relation to nonmental entities. Surprisingly, such diversity is not typical o perceptual theories. Concerning the perceptual realm, there has been rare philosophical agreement in the form of perceptual dualism. Although this view has several versions, its basic assumptions are quite commori. This prevailing view attempts to set out a framework in )v'uch ontological and epistemological gaps would appear to be bridged o certain extent. The rest of this chapter is devoted to this importan a influential view. < Perceptual dualism postulates a dichotomy between two pcrccp stages, contentless sensation and contentful perception, "cnee name?3 Perceptual dualism should not be confused with mm dualism, which claims that the mind is a separate substance .m, ■ body. Although the two views arc not contradictory (and are in often conjoined), they are not identical. In perceptual dualism, u i > in the two perceptual stages of sensation and perception, rather the two substances of mind and body. , . Perceptual dualism emerged as a prevalent view in the seventeenth century (although there were somewhat similar views before then) ana took on the character of a more coherent system in the eighteen th and nineteenth centuries; by our own century the signs of its decline cou already be discerned. My principal concern here is , rrl-»;rai historical development of perceptual dualism, but to un e 1Oueh exposition of this approach. I will conclude by suggesting that although perceptual dualism has raised many important issues, “ «a of nouml reception chamber in the mind which is unaffected by the agent s personal characteristics. The events in this chamber (i.e., sensations) consist of mental stuff, but their creation involves a mental response which is constant in relation to a given stimulus. The changes that the mental system undergoes do not influence the nature of the initial mental response. All of the developing personal characteristics (memory, belief, desire, motivation, emotion, expectations, etc.), which constitute the mind, do not influence the stuff in this chamber. According to this approach meaningful content stems precisely from such personal characteristics; hence, their absence implies that the stuff in the reception chamber is contentless. Since the postulation of the stage of contentless sensation is primarily the result of theoretical considerations rather than of empirical description, the empirical identification of this stage has been a source of constant dispute. Among the examples that were given for such a stage are secondary qualities such as color, sound, pain, and thirst, infant perception, and theoretical entities such as sense data. Examples of perception are less problematic (since they are compatible with our
The Emergence of the Pcrccivcr
13
everyday notion of perception). They include primary qualities such as distance or motion, and meaningful objects and events such as a pretty girl standing beside a table, or a stone shattering a window pane. The postulation of a pure sensory stage is the unique feature of perceptual dualism. The major role of this stage is to overcome the ontological and epistemological gaps that isolate the mind from nonmcntal entities. This stage is mental but it lacks the feature which is so typical of mental states: meaningful content. Because of this intermediate stage (and the mind’s isolation) there is no direct perception of external objects, merely awareness of their mental representation. As Spinoza argues, “the human mind docs not perceive any external body as actually existing, except through the ideas of the modifications of its own body.” Similarly, Russell claims that "all that you sec must count as inside your body." And the psychologist Attneave argues that "what we experience as the ‘real world’, and locate outside ourselves, can not possible be anything other than a representation — of the external world.” The world we experience consists, as it were, of “Morse code signals” of the external world. Likewise, Minsky argues that our experience of being in the outside world is “a complicated illusion. We never actually make any direct contact with the outside world. Instead, we work with models of the world that we build inside our brains. ... For a child, learning about the spatial world beyond the skin is a journey that stretches over many years.”24 By this view, perception of external objects is usually indirect in two basic senses: it is not a direct awareness of the external objects but of internal sensory entities representing them; and it is preceded by mediating cognitive processes which enrich the impoverished stage of pure sensation with information about the external objects. The sensation-perception distinction is based on the postulation of a number of factors that arc traditionally assumed to be involved in the causal process of perception: (a) the stimulus source (or what is inadequately called the “distal stimulus"), for instance, a table; (b) the stimulus (or what is traditionally termed the “proximal stimulus”), for instance, the light rays coming from the table; (c) neurophysiological processes; (d) sensation; (c) cognitive processes; and (f) perception. The major relationships among these factors are as follows: 1) The relationship between the stimulus source and the stimulus is equivocal; that is, the latter docs not uniicquivocally specify the former. 2) Sensation does not exhibit any degree of independence from the stimulus or its neurophysiological effect; therefore sensation docs not involve active mental contributions. 3) Sensation cannot reflect the stimulus source. 4) Perception involves cognitive processes that overcome the cquivocalncss of the stimulus. 5) Perception docs not correspond with the stimulus, but rather reflects the stimulus source.
14
The Perceptual System
In light of these relationships, the principal assumptions of perceptual dualism arc as follows: A) Sensation is meaningless; it lacks any cognitive or evaluative content. B) There is a constant one-to-one correlation between the (proximal) stimulus and sensation; hence, the agent’s past experience, emotions, expectations, will, and other personal characteristics have no influence on sensation. C) There is a difference between sense reception and sense perception; the former is contcntlcss and the latter is contentful. D) Meaningful content is added to sensation by the mind through cognitive processes such as inference, interpretation, computation, association, and elaboration. This added content is often assimilated into sensation in such a way that it can be separated again only by reflective analysis. These assumptions may be divided into two groups. The first two assumptions refer to the contcntlcss sensory stage: assumption (A) postulates the existence of this stage, and assumption (B) describes its origin. The other two assumptions indicate the place of this stage in the whole perceptual process: assumption (C) points to the existence of another perceptual stage, and assumption (D) characterizes the transition from the sensory to the perceptual stage. According to the first assumption, what we actually sense are not the meaningful everyday objects and events, but something devoid of cognitive and evaluative content. Therefore sensation is not to be regarded as knowledge, but merely as a response to external stimuli which arc neither true nor false. It is a point of departure which is given to the cognitive system. Russell, who clearly e~erses the approach of perceptual dualism, argues that “The sensnens caused by external objects arc events like any others, and have r:: the characteristics that we associate with the word 'cognition .- Since sensations lack any cognitive content, they cannot be false: there is nothing in them that can be mistaken: ’’There are in fact no illusions of the senses but only mistakes in,interpreting sensational data as signs of things other than themselves." In this view, sensation does not have any evaluative component either; it is neutral in this respect. The happiness we see on someone s face, or the danger we perceive in a certain situation, are to be considered as later subjective additions. fhe second assumption deals with the cause of the contention 1 r,n • general thesis is clear, namely, that the cause is in the contributions onhp^^a0” “ a mCnta> stagc’ paSSIVC and invo,untary ■ t^e nunc^ m crcat^g arc not excluded; after 'ill
“b S” h”S
T' “bc r°,“nd
such as one’s past'exnerien^ % “ nc,lhc" Pcrsonal characteristics mental process such"asth'l’ Cm°r°nS *nd cxpcP ‘ category is of less importance than in the binary category ‘ ‘, • boundaries of the former category arc indefinite. Drawing t w x ‘ is to a peat extent arbitrary'. In nature no boundary is ixei
category is autist.
varying degrees of complexity 1 he
inert and mechanical conception of matter in the seventeenth centuty n now been replaced by more complex notions. 1 oulnun a g • . current physical theory has abandoned the Cartesian msistcn tnnECr by contact and collision. Authentic physical processes ate treated as merely transfers of momentum and energy from on another through the contact or collision of solid, impenetrable partly Rather, the basic interactions of quantum physics arc, y, standards, field processes. Likewise, modem physics sp self-powered and self-regulating machines. According to ou „ ’ " the key terms of physical science, namely, “force, energy, been "particle," “brain," “nerves,” “cause” and “explanation, na modified in modem physics. This conceptual change, wluc ~oti0n of last century', has shifted the emphasis from the mechams i es Qf isolated particles to the activities of whole systems, such as within a whole field.42 In this way more properties have been inc rcaims the physical realm, and the gap between the physical an of has been reduced considerably. For example the P 1 can self-regulation or feedback, which is characteristic of ration now be attributed to physical systems as well. , USUally The inclusion of more properties in physical sys c*P'ctjon of the been construed as supporting materialism, that is, a re u . that mental realm to the physical realm. My view is differen . properties mental properties are properties of systems that have pnysl *. • c(j by as well does not imply that mental properties can be tuny referring to the physical level. , . , „ j mental In view of the gradual nature of both the physica realms, a continuity rather than an unbridgeable gap o W , assumed between mental and physical states. So, the mental-p y ^at between inorganic bodies and lower animals is much narrower between inorganic bodies and the rational conscious mind. • Following this line of thinking, Toulmin argues that no• feature distinguishes all of the rules and regularities of human M and conduct from the laws and uniformities of physical n. urlj: suggests eight basic types of human conduct: mental conjunc i . regular practices, rule-governed patterns, rule-conforming conduct, ga and signals, rule-applying conduct, rule-following conduct, and ration criticism of procedures. These create a continuum that replaces t e traditional dichotomy between the physical and the mental realms. I here is no clear point, Toulmin claims, at which we are taken all at once out of the realm of matter and put into the realm of mind. Rather we move along the mental realm from states which appear closer to physical states
Mental States
51
than those which are more and more like typical mental states.43 (In this book, when I refer to mental states I mean only those typical states which have at least one and usually both basic dimensions of the mental realm: feeling and intentionality; plants, which seem to lack these dimensions, are therefore not included in this category of the mental realm.) The gradual development which is assumed to occur between physical and mental states does not imply that new properties do not emerge. Mental states arc new emergent properties. Because of their newness, reference to previous states cannot fully explain their emergence. I lowevcr there is a difference between a partial explanation and no explanation at all. The assumed gradual development provides some sort of partial explanation for the emergence of mental states. Similarly, the assumption of a continuity in the mental realm does not exclude the possibility of instances of local discontinuity. We may assume that in light of their rapid cognitive development there is a significant difference between people and brutes; but this difference does not constitute a dichotomy expressing an unbridgeable gap. Despite this difference my general contention remains intact: mind and body are not two substances separated by an enormous rift. Between what are regarded as purely physical states and purely mental states there are intermediate states which may indicate a general direction of the development of mental states. Abandonment of the traditional dichotomies (or of binary categories) by which the mental realm is described, and recognition of the diversity of mental states (and hence of the need to work with categories that have an internal structure) together represent an important step toward adequately describing mental states. To summarize, the traditional mind-body problem has often been formulated as the problem of how a mental entity can be causally related with a physical entity if there is an unbridgeable gap that separates them. This prevailing formulation contains three basic assumptions: (a) the mind is an entity (thing) in the way that the body is; (b) the relation between mental and physical entities is causal; and (c) there is an unbridgeable gap between mental and physical entities. I have challenged these assumptions by proposing three alternative assumptions, (a) The mind consists of dispositional and actualized states rather than of internal isolated entities. Ascribing these states to living organisms is in essence similar to ascribing other states to other kinds of systems, (b) There is no actual separation between mental and physical states, and they represent two different levels of describing the same thing. Mental states emerge out of a certain complex physical, or biological, system, (c) The emergence of mental states is not miraculous. There is more or less of a continuum of biological and mental states ranging from simple states (whose regularity is close to strict physical regularity) to more complex states (which have to be explained by referring to many nonphysical features).
52
The Perceptual System
In this approach, the mental-physical gap has been contracted in e senses. First, mental properties, like physical ones, arc properties ot a system and not separate entities within it. Second, instead of positing «o separate substances, we assume that the mental and physical realms are two different aspects of the same system. Third, the gap is reduced y assunung the possibility of an evolutionary process in which increasing!} complex mental states emerge alongside increasingly comp ex physical structures. An atom or even a neuron is not sufficiently comp ex to support mental states. Hence mental states cannot be located in, or corre ated with, merely a single neuron. Only a very’ complex group o neurons can furnish such a supporting basis. The more complex the neur asis, the more complex the mental states that emerge. The ese opment from lower animals, or even from plants, to human beings is an example in point.44 This does not deny the difference between the ment an physical realms, but rather the assumption that they stand at opposite poles with no conceivable way to connect them. n some views the mental-physical gap is contracted in only one th 'u° ° * C above senses; this does not seem to be sufficient for solving 6 Pro^ematic relation. Spinoza eliminates the second (and maj e t e irst) kind of gap and treats mental states as not being separate rom p ysical states. But since he regards mental states as being very is inc , m the sense that there is no process of development connecting em wit other states, the basic problematic issue is not resolved. It may e surpnsing to find, however, that all three assumptions are implicit, in one onnu ation or another, in Aristotle’s view of the soul. Little wonder, en, at Anstotle should have been unperturbed by the mind-body gap a so notonously troubles modem philosophers. As Smith and Jones pu i , or an Aristotelian the “question 'what is to have a mind?’ is not \vhatS 'TrV°-Tt 3 spec*ai °f entity, any more than is the question ls e. □ have a mind is not like having a heart, it isn’t to have canadf COmp™ent or constituent: rather, it is to have a set of tvniral a^rr ° discussion I have sought to overcome some of the arrentaki i”' tbe y^nst°tdian approach, thereby making it more acceptable to the modem critical thinker. manne S°fgested Gratification approach presents the mental realm in FTnbnatiJ w *S mOre natural and makes it more amenable to bv usinv p11 l Cnt^ properties arc natural properties that arc explained srientifir pv”i tools which indispensable to both everyday and tok in conSatl°nS: °nce this view is ad°P,cd’ our main explanatory
magic bridge ora m reahn ‘S "° 10ng6r constnlct a existence of such a □□ • ‘r°ubleisome mind-body gap, since the very describe the various P 1S t0 a certain extent; the task is rather to us W65 of mental states.
Mental States
53
(2.5) 'lite Basic Menial Dimensions: Feeling ami Intentionality
So far I have principally concerned myself with the conceptual tools that are required to describe the mental realm. I now go on to consider the two basic mental dimensions: intentionality and feeling (or sensation). Intentionality refers to a relation between subject and object (the latter of which can be imaginary), whereas feeling expresses the subject’s own state. When Dean secs or is in love with Jesse, the feeling dimension is expressed in a particular feeling (say, a thrill) that he experiences in seeing or being in love with her; the intentional dimension is expressed such that his sight or love is directed at Jesse. The feeling dimension comprises a variety of feelings (or sensations) which may be classified as belonging to two basic types: (a) global feelings such as drowziness, restlessness or repletion; and (b) localized sensations as in most varieties of pain and sensory pleasure. The intentional dimension includes various references to objects such as those involved in perception, memory, thought, drcams, imagination, desires, volitions and emotions. Generally the agent is more active in the case of the intentional dimension than of the feeling dimension; feelings just seem to happen, and when they arc intense we are overcome by them. Typical mental states in human beings have both dimensions; but these dimensions vary in type and degree in different mental states. The intentionality of moods is not as complex as that of thinking; but the feeling dimension is usually more intense in moods than in thinking. The term “feeling" has various meanings: awareness of tactile qualities, emotional attitudes, moods, awareness in general, and so forth. However when applied in its strict sense, the term, as Sully argues, “is confined to those modes of consciousness which arc in a peculiar sense affections of the subject, and which do not, in the same direct way as our thoughts and volitions, involve a clear reference to objects.”4" My own use of the term is similar to Sully’s. The feeling dimension is a mode of consciousness associated with the agent’s own state. This mode is usually part of a complex mental state which includes the intentional dimension also. The feeling dimension is the lowest type of consciousness, and unlike higher types of awareness (such as those found in perception, memory and thinking) it docs not have a meaningful cognitive content. It expresses the agent’s own state, but is not in itself directed at this state. Since this dimension is a mode of consciousness, one cannot be unconscious of it; there are no unfelt feelings. The homogeneous and basic nature of feelings (sensations) makes it difficult (though perhaps not impossible) to describe them. Indeed there are very few words for feelings, and we often have to resort to metaphors and other figures of speech in referring to them. It is not easy to identify the various features of the feeling dimension. No doubt feelings have intensity, duration and some have location as well; but what other qualities do they have? The qualities of being painful or pleasurable arc obvious qualities of this dimension. Can we further analyze these qualities? Are pain and pleasure the only poles of this dimension?
54
The Perceptual System
two other'bid'c5 lba'.cxc‘,cntent-calmncss and tenseness-relaxation form that each d L?”T °f *hc feelinB dimension. Hume even claims quality Without S .cmollon has a distinct, unanalyzablc feeling s^em ^fe to sav th ,hc ma,tcr a( lcn^h' however, it would the bask albeit T0”" °f p,casurablc Pa''iful qualities are To comnlir C °n ^’ cons**tucnts of the feeling dimension. pleasure are not ? ° mattcrs even further, Ryle has argued that pain and a feeline that r COUJn,erParts of a single dimension: while pain is HnS s^ l°Cutcd' pIcasure is "o'-47 I agree that pleasure has to feeling the on' ".’lcbls c'oser in meaning to the emotion of joy than cont^nsinte t PP| 6 °f pain' In this sense pleasure, like emotions, use the teS. ■Eu±^n,SfSuch as value judgment. Here, however, I painful fcelingPIn the J> *° “ cnJ°-vable fcclinB as opposed to a feeling of nainmn k mor? ?cncral s=nsc of the term “pleasure the or in hard but saticr^311 °Pa P'casurablc experience; for instance, in sex feeling which i th ’'U1® In the second sense “pleasure” refers to a
Sat^ly u^U^T5^ °f Pain' S° that pain in this
"
particular mpntoi ♦ « Sometimes the feeling dimension involved m a pleasure (in both senses^Th^^^5 eIemcnts’ such as both Pain and romantic love SES ' ^US 15 °^Ien " hat happens in cases of intense distinimish^uL? type of awareness. However, we should (what some peopV^aT^T-n C°nSt'tutc5 the raw feeling itself awareness of th„ • Tuaha ) and the second-order complex distinction, which is'™^ fcatuJcs associated with this feeling. This is nevertheless useful „obvious from a phenomenological point of view, dimension, that is ct,. Umran men,al states that have only one basic rarely if at all Actual °f pure feelings or pure intentionality, occur typically have both dim„mEnta state.s comP,cx experiences which not a mental state . nacnsions- 'n this sense, an isolated belief is usually feeling is usually only” * comP°ncnt of such a state. Similarly, a raw An intense feeling ’ °ne cornP°nent of a complex mental experience, experience, but not thi^ i bc lhc dominant component in such an a complex experience ’ cornPoncnt- Thus, the experience of pain is awareness of the va ' ' lnv°h'*ng a raw feeling and a second-order feeling: location durafUS propertles tbat are associated with the raw effects on the well-b '10n' Slm’'abty to other feelings, evaluation of its determine the aversiven*18 °r agent’ ancl so on- These properties are two basic compo WS °‘tbe experience of pain. Accordingly, there character of the exn0^5 °P pa‘nPu' experience: (a) the qualitative aversiveness of the exS“’ ..T*.™'/ ,hc raw feeling, and (b) the the agent. P nencc which is an indication of the suffering of Although it is ha H they are sometimes inden d'st'n?u'sh between the two components, undergone a lobotomv n ent P *S °f'cn rcP°rtcd by people who have acupuncture, that the na’ °r ”ave bccn 'rca'ct' with narcotics or has any aversive effect , pers.lsls (in 'he same intensity) but it hardly reating chronic pain sufferers, it was found
Menial States
55
that morphine altered the aversive component but left the measure of the intensity of feeling intact, whereas aspirin altered both components.41* It is obvious from other everyday cases that pain tolerance docs not correspond to the feeling component. Sometimes people can separate the feeling of pain from the annoyance caused by pain. The component of avcrsivcncss is often determined by cognitive, evaluative and other intentional properties, while the component of feeling depends more on properties associated with the stimulus and the physiological harm. Harm and suffering arc therefore not the same thing. ' Intentionality is the relation of "being directed at something.” This relation can be understood as merely referring to a future state of a system, such as the state in which the system will be, given its present circumstances and regularity. Here “directed at” is similar to "tending toward.” When intentionality is taken in this sense, which is close to the Aristotelian notion of "final cause,” inanimate things too may have intentional stances. However the intentional dimension in mental states refers to a more specific sense of “being directed at,” that is, of “being about something.” The feature of “aboutness” is generally indicated by the word “that” following the intentional term, as in “I hope that...,” “I believe that...,” “I sec that...” and so on. Here, aboutness is not a passive relation of “tending toward," but involves our cognitive capacity to separate ourselves from the physical stimuli that surround us. and to create a meaningful subject-object relation. In this case, the intentional object is not some future state of the system, but rather an object about which the system has some information (which, of course, can be mistaken). Something about which we have no information at all cannot be our intentional object. When Tom's intentional state is a fear of snakes, then Tom must have some information about snakes. And if Mary’s gaze is directed at John, then Mary must have some information about John. It is from the cognitive feature involved in intentionality that a typical aspect of intentional states derives: their description exhibits referential opacity, that is, the nonsubstitutability of different descriptions of the same object in some contexts. A substitution of terms referring to the same object may change the truth value of the description. Consider the following example: 1) Ruth hopes that the pel person approaching her is not Bill; 2) The person approaching Ruth is Bill; From these statements we cannot conclude that 3) Ruth hopes that Bill is not Bill. Referential opacity stems from the agent's cognitive capacity to view objects from various perspectives. One may view a certain object as a chair, or a comfortable object to sit on, or a favorite piece of furniture, and so forth. An agent who knows only some of the possible perspectives of the subject has a limited view of it. Viewing the chair as a comfortable place to sit need not entail viewing it as a favorite piece of furniture as well. Since we arc not aware of all perspectives, they arc not equivalent for us and we cannot substitute them. Since an intentional
56
The Perceptual System
state involves the cognitive feature of viewing X as Y, in describing that state we cannot substitute Y for Z (even though they arc equivalent from another perspective) if we do not have the new perspective, that is, if we do not view X also as Z. Intentionality presupposes a certain cognitive activity; this docs not imply that the resulting intentional state is always true or directed at objects which have physical existence. (Intentionality does not only consist of cognitive activities: evaluation, for example, is another type of intentional activity.) The feature of referential opacity is absent from the broader sense of "being directed at.” This sense docs not necessarily entail the complex cognitive system that is involved in intentional states. 1'his is exemplified (though not proved) in the following argument: 1) The thermostat is directed at 20°C. 2) The most comfortable temperature for humans is 20"C. Contrary to the feature of referential opacity, we may conclude here that, 3) The thermostat is set at the most comfortable temperature for humans. The involvement of a cognitive capacity in intentional states results in having different grades of intentional systems, as there arc different grades of cognitive capacities. Thus, we may speak about first-order intentionality (c.g., X believes that P), second order intentionality (X believes that Y expects X to believe that P), and so forth. The second-order intentional system exhibits more complex knowledge than the first-order system. The greater the number of possible aspects that the system is able to grasp, the higher the system’s intentional order. The different grades of intentionality are important for describing the development of the mental realm. Complex types of intentionality arc not found in animals. Although animals can refer to something which is not in their immediate environment, they do so in a much less determined manner than humans. Accordingly Wittgenstein observes: "We say a dog is afraid his master will beat him; but not, he is afraid his master will beat him tomorrow. Why not?"51 In a somewhat similar vein, Aristotle suggests that the difference between the imagination of lower and of higher animals concerns their dcterminacy; the imagination of lower animals is indeterminate.52 Because of their primitive intentional capacities, animals arc more enslaved to the present than people. Animals deal merely with information which is biologically oriented, whereas humans often deal with biologically pointless information (as, for example, in the case of art). In general, all cognitive capacities, such as thinking, remembering and imagining, which require a complex order of intentionality, namely, the ability to refer to some meaningful content beyond immediate stimuli, exist only primitively in animals. An intentional stance involves the agent’s ability to refer to various possible aspects of the object. The greater the complexity of these capacities, the more relevant and appropriate considerations concerning the intentional stance become. The higher complexity of the intentional system in human beings enables them to carry out their typical activities, for example, a
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purposeful activity referring to circumstances beyond the present. (It is probable that primitive forms of such an activity can also be found in higher animals other than man.) We engage in such an activity not for its own sake but because we want to achieve some future goal. I'he reference beyond present circumstances is also an essential feature of moral deeds and aesthetic experiences. Deprived of the ability to make such a reference, human beings would remain enslaved to the present. The cognitive system that underlies intentional states expresses an important stage in mental development, in which a creature is aware not only of changes in its own conditions, but also of the factors responsible for these changes. Initially, having merely perceptual capacities at its disposal, the creature is aware only of its immediate environment; this is the case of neonates and most animals. Later, when other mental capacities arc acquired, for instance, imagination, memory, emotions, and thought, there emerges the capacity to abstract from the concrete and immediate environment, and to represent things that are not present. Consequently, a more complex and general understanding is achieved which refers to many aspects of reality: practical and nonpractical, actual and possible, presentational and representational features, and so on. The development of intentional capacities involves a greater degree of self-consciousness as well, making it possible to understand the connection between motives and behavior, and producing more useful conduct. Human beings respond not merely to simple immediate stimuli but also to complex past, present, future and possible states. Cognitive references of this sort obviate the need to confront the environment head on, and so eliminate the hazards entailed by such behavior and reduce the demands that it makes on the agent’s resources. These intentional references are also more rapidly achieved than direct physical contact. All of this makes for an unquestionable evolutionary advantage. The intentional character of most mental phenomena allows, apart from common causal explanations, teleological explanations as well. Like the teleological object, the intentional object is not something inside the mental state but is something to which the mental state refers. This reference cannot be fully captured by merely causal explanations. The development of intentional capacities allows the emergence of another important mental capacity: free will. Without getting into the philosophical difficulties concerning free will and determinism, it is clear that the development of intentional capacities is a necessary (though perhaps not sufficient) condition for the emergence of free will. Only when we have a sufficient degree of knowledge about possible events in the environment and of self-knowledge about our own capacities can we freely choose a certain course of activity. Freedom implies knowledge of alternatives, an important feature of intentionality. The intentional dimension clearly demonstrates the complexity of the mental realm and hence its various distances from purely physical states. The feeling dimension lacks a comparably complex structure and is often regarded as more primitive than the intentional dimension. Although Descartes assumes that animals arc merely machines, he
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nevertheless admits that they can feel pain and pleasure. Another reason or placing such feelings at the bottom of the mental scale is that they lave a spatial locus just as physical properties have. In light of the foregoing characterizations of the dimensions of cn lonalitv and feeling, it is clear that raw feelings arc not intentional ince hey arc not about meaningful content either. Feelings arc the simplest form of awareness. They do not involve discrimination of an ° f 'T 'tS background, and they therefore do not have meaningful on ent either. Feelings arc not propositional attitudes; they have causes u not intentional objects. This is contrary to Brentano’s tenet that a property is mental if and only if it is intentional. To salvage Brentano’s enct, one might argue that feelings are directed at their location. It could e asserted that a painful feeling is directed at injured parts of the body, uch a claim would be mistaken however. Painful raw feelings may be expenenced in a particular area, but they are not about that area; they o not include any cognitive content describing that area. We say that ''e are sorry about the situation rather than that we arc pained about it. omow is an emotion which is directed at a certain situation. A painful eeling expresses the agent’s own state, for instance, the disagreeable state of an organism that has sustained an injury. These feelings may be intentional objects of more generalized experiences such as self-awareness, but this does not make them intentional. My desk is the intentional object of my immediate perception, but desks arc not intentional states. Brentano’s tenet can be salvaged if we recall that feeling is one dimension of a more complex mental state that has an intentional dimension as well. Mental states can be intentional, while encompassing nonintentional components that belong to the feeling dimension. The cognitive separation involved in intentionality emerges in two pnncipal stages: (a) our separation from the stimuli which impinge on our sensory receptors, thereby creating our perceptual environment; and (b) our separation from our immediate perceptual environment, thereby enabling us to refer to items that are not present, such as the objects of thinking, remembering, imagining, and the emotions. The cognitive separation is greater in the second stage. Accordingly, in this stage the agent s will plays a greater part in determining the intentional content (I can choose the content of my thinking, memory, and wishes in a way that 1 cannot choose the content of my perception); and the content has a greater degree of indeterminacy (I can think of a woman without conceiving of her as being of a particular height or as having a certain color of hair, but I cannot sec her in this way). Moreover, the second stage involves the emergence of the capacity to grasp the distinction between the world as it is taken to be and the world as it is. These two stages may be divided further: we can divide perceptual intentionality into hat which is typical of sight and that which is typical of touch; the second stage may be divided into intentionality typical of memory and ^thinking (see also 3.3). The intentionality associated with tanking is the more complex since it can go beyond the present
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surroundings of the agent. Remembering is limited to content that was previously the object of a different intentional experience; thinking and imagining do not involve such a limitation (there may be, however, a type of perceptual imagination which has this limitation). The continuity in the emergence of mental states, that is, the development of mental states from nonintentional feelings to complex intentional capacities involving a developed subject-object relation, makes possible the explanation of the emergence and nature of the mental realm. The subject-object separation is thus a product of a long evolutional^ process, in which we have become aware first of changes in our own situation and then of our environment, first the immediate perceptual environment, and then the more remote (actual and possible) surroundings. Although primitive forms of intentionality such as perception manifest cognitive separation between creatures and their surroundings, it was not before the emergence of a complex mode of thinking had developed, in which there was a greater measure of reflexivity, that the implications of such a separation were fully realized, and the relationship between subject and object became a central problem in epistemology. Primitive people did not think of themselves as being separate from their surroundings.53 However awareness, or realization, of the intentional separation is different from the separation itself, and the absence of the former does not imply that the latter is wanting as well. For the intentional dimension to emerge, a further development is required beyond the stage of the feeling dimension, which is the more primitive mental dimension. For example, it seems that a fetus is capable of distinguishing pleasure from pain before its intentional capacity has evolved. So, too, a developed intentional system cannot plausibly be ascribed to low forms of life, such as bacteria, which have sensitivity only to changes in their own conditions; this type of sensitivity resembles the sort involved in the feeling dimension. Responsiveness by an organism to changes in its conditions, and particularly to injury, is of utmost survival importance. It is plausible, therefore, that awareness of such changes should have developed first, and in such a manner that the organism might be attentive to any injurious change and be compelled to end it.54 One can speculate about the evolution that has taken place in the feeling dimension. I would suggest that global feelings (such as pleasure, tranquility and tension) may perhaps have developed first, and the emergence of localized feelings (such as a toothache) may reflect a higher state of development in which a creature has the capacity of being aware not only of a change in its conditions, but also of some of the properties of this change, say its location. In this regard, localized feelings are closer to intentional states than are global feelings. There arc also feelings that can be both global and local (e.g. feeling hot, cold or chilly). It seems that full intentionality implies a capacity for singular reference.55 Global feelings lack such a reference and localized feelings may express a primitive form of it.
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I have pointed out three major steps in the development of cognitive capacities: (a) sensor)' sensitivity to changes in the agent s conditions, as in the case of pain; (b) perceptual knowledge of the agent s immediate environment; and (c) knowledge of the sort which is found in thinking and which can refer, among other things, to the agent s own attitudes toward other things. Since each type expresses a higher stage of development, this is apparently the order in which these capacities evolved. From an evolutional)' point of view this order makes a lot o sense. For the purpose of survival the creature should first have some sensitivity for changes in its own conditions, then it can have some knowledge of its immediate environment, and only then can self-knowledge of its own attitudes and knowledge of more rcmo e We may now refer to the classical dispute whether self-knowledge is prior to knowledge of external objects or vice versa. Sensi ivi y changes in the agent’s conditions is prior to the agent s know c B external objects. But this sensitivity is not, strictly speaking, know g , it has no cognitive content. In this sense (perceptual) know c 8 external objects is prior to (conceptual) self-knowledge. It also seem thinking about other objects is prior to thinking about oncscl.. ( appear, however, that it is often easier to remember our own cc mg. attitudes than the details of what actually took place, tins y' connected to the fact that we remember best what made a sigm impression on us.) . , ■ t a This process of evolution indicates that the min is , mysterious substance which appears suddenly, but rather i states have evolved gradually into ever more complex s a cs . , increasingly different from physical states. Feelings arc closer o p y states than are intentional states. Unlike other intentional states dui < physical states, feelings usually have a specific spatial location, I have a more specific duration than intentional states. c cscri 5*18 as being in a tooth and as lasting, say, seven minutes or cn mg < ■ in the morning; we do not describe our emotions or m°u8“ . This similarity with physical states is also demonstrated by £ (‘ it is more natural for feelings to be explained through re ere neurophysiological causes (as when we explain a feehng o pa referring to an injury) than for emotions or thoughts to be exp am
Typical mental states in human beings have both an intentional dimension and a feeling dimension. When one of these dimensions predominant, the other often recedes so that it is hardly notice , an in extreme cases may not be noticed at all. It is known for examp e ia seriously wounded soldiers often feel almost no pain while on c battlefield, and only begin to experience severe pain from their woun s when they are evacuated. While in combat they had been absorbe in their intentional object (the battle or the enemy), so that the feeling dimension was pushed into the background. Likewise, diverting attention away from a pain and focusing on other things instead may diminish or
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even banish it altogether. Another possible remedy for pain may be to concentrate on the pain itself, rather than to divert one’s attention from it.56 Concentrating on the intentional dimension (which in this ease happens to be directed at the pain itself) may to some extent override the feeling dimension. The placebo effect may also be interpreted as a case in which the centrality of the intentional dimension reduces the intensity of the feeling dimension. Feelings of pain or hunger may also diminish when one is deeply involved in an intellectual activity. Intense moods such as intense apathy or depression may exert the contrary effect by setting aside complex intentionality. The inverse relation between the complexity of the intentional dimension and the intensity of the feeling dimension is typical of cases in which the level of activity of the mental system remains constant. However when the level changes, as in the case of old age or situations of intense agitation, both dimensions may change in the same direction.
R e>4
CHAPTER 3: PERCEPTUAL STATES In this chapter I begin to present my view of perception. First I suggest the conceptual tools with which we should describe perception. Rather than describing perception as being made up of internal subjective entities, perception, or, rather, perceiving, should be characterized as an intentional state of direct awareness of the environment. (The term "perceiving” is preferable since it does not imply the existence of an entity.) Perceiving is not an isolated entity within the physical space of one's head; it is a continual experience, or activity, which is complete at any moment. The pcrccivcr docs not encounter meaningless sensory data and then convert them into meaningful perceptions; rather, the perceiver directly encounters a meaningful environment. Like other types of cognition, perception is relational: it expresses an agent’s particular perspective. Perception, however, is not necessarily relative (in the sense of being indeterminate and unspecified). The ontological status of the perceptual environment is another major issue of this chapter. 1 argue that this environment exists on a different level of description from the physical world, and that its existence presupposes the existence of a pcrccivcr. This view is a type of critical realism or a moderate subjectivism.
(3.1) Initial Characterizations Since the seventeenth century perception has usually been assumed to consist of internal subjective entities. This characterization is based on the internal-external and subjective-objective dichotomies and on the assumption that the mind is a separate substance, or that it consists of separate mental entities.1 Such a description may have some explanatory value for an initial understanding of perception, but it raises too many difficulties if used as a comprehensive theoretical framework. In the preceding chapter I explained some of the disadvantages of 1 as consisting of internal entities. The internal-external seeing ■'the mind
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and subjective-objective dichotomies in their traditional formulations should also be abandoned. The first dichotomy has physical connotations which cannot adequately describe mental entities (although we do speak about headaches, backaches and other mental phenomena which do have physical locations). Moreover, since the internal space within the head is also a physical space, and in this sense docs not differ from an "external” space, we gain nothing by moving the perceptual environment inside the head. This spatial metaphor is closely connected to the assumption that perception consists of entities. It is natural to ask about the location of entities. Once we abandon the characterization of perception as consisting of internal entities, the third remaining feature of that characterization (i.e., being subjective) will take on a different meaning.2 Instead of characterizing perception as a collection of internal subjective entities, I suggest it is an intentional state of direct awareness of the perceptual environment. The various components of this characterization will be explained in stages. (A) A state. A state is a combination or organization of attributes. In a description of a car’s behavior, its wheels or engine arc not states, but entities (things). Similarly, in a description of person s behavior, t e eyes and brain are not states (though like wheels and engines they are in a certain state); perceiving and thinking are states. A state is define as a combination of attributes, so if questions about its spatial location are to have any meaning at all they must refer not to a spatial point u o a whole field (system). The question “Where is the car s engine, oca e . has a precise spatial answer. The question "Where is the car s sta c o being in motion located?” is less clear and should be answcrc in erms of a field. The same applies to perception. When perceptions are c me as internal mental entities, questions as to their spatial location arc natural but have no meaningful answers; this suggests the flaws o a definition. When perceiving is defined as a state, inquiries a ou is spatial location are usually neither natural nor meaningful. (. imiary, T.S. Eliot says that “Hell is not a place but a state.”) A more natural ana meaningful question will ask about the field (or realm) to which a cer am state is related. A perceptual state is not located at some point inside the interior space of the organism but is related to a field which includes the organism and its perceptual environment. Similarly, a state of hostility between two countries is not located at some physical point in those countries but is related to a field which includes these countries. I his field is not merely a spatial one; it involves other factors as well. Ryle s classic example concerning the concept of “university" is revealing on this point. A foreigner visits the colleges, libraries, and administrative offices of Oxford; he then asks, "But where is the University?” It must be explained to him that the University is not in a particular spot on the campus. Rather, it is the way in which all that he has seen is organized. In the same vein, perceiving is not the eye, the brain or the particles around us. It is the way in which all these factors, and others, are organized.
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(B) An intentional slate. According to the dualistic approach to perception, internal perceptual entities exist as mental pictures or similar kinds of representation. We see these pictures, and then infer properties belonging to external objects. There arc difficulties in this indirect approach: the relation between the internal picture and the external object, the need to postulate a little person inside the brain who looks at these pictures, the location of these pictures, their exact features (c.g., if they arc green like the green object they represent), the ways in which the subject interprets them, and so on. In my suggested approach perceiving is considered an intentional state directed at meaningful objects and events in the environment. Just as there is no general opinion without content, there is no general perception without content. One cannot see without a particular thing being seen. The intentionality of perception, namely, the reference to environmental features, makes unnecessary the postulation of internal entities which represent the environment. The problem of describing the relationship between the two is thereby avoided. We perceive the environment and not our own perceptions. Since intentionality involves a cognitive capacity and perception is an intentional state, perception involves a cognitive capacity by which we acquire information (or belicf-Iikc states) about our environment. An important advantage of a belief-acquisition approach over the representational, indirect approach is that the former is not circular. It does not explain the perception of external things in terms of perception of internal things.3 (C) An intentional state of awareness. In the approach presented here, awareness is an essential feature of perceiving. We do not perceive something first and then add awareness to our perception. Perceiving is itself a state of awareness. Perceiving is a cognitive state of being aware of the perceptual environment or of simply being in that environment. (The latter formulation stresses the inseparability of the perccivcr and the perceptual environment; sec 3.5.) Whereas I use the term “perception" to refer to sense perception, I use the term “awareness" in a much broader sense. It refers to all types of awareness: thinking, remembering, perceiving, imagining, feeling, and even dreaming. Characterizing perceiving as a cognitive state of awareness requires that a distinction be made between perceiving and mere physiological registration. The latter involves processes that the organism is usually not conscious of. hollowing Dretske, we should distinguish between two notions of information: the physical and the intentional.4 Information in its physical, non-subjective sense is a two-term relation: it involves a certain specification, a particular relation between two things such that changes in one are expressed in the other. In its more common use, information is a three-term relation also involving the agent's belief in, or appreciation for, the connection in question. This is an intentional notion of information which presupposes the existence of an intentional system. The ability to turn the stimulus into an intentional object is what distinguishes mere physiological registration from perceptual awareness. This is the difference between cameras, photocells, and eyeballs on the
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one hand, and the visual system of the pcrccivcr on the other; the former ye blind.' Since the camera does not "see” the stimulus as a separate intentional object, the sensitivity of the camera involves merely physical information. This physical sensitivity is not perceptual awareness. Only a small fraction of the physical stimuli registered by the neurophysiological system arc expressed in perceptual awareness. Photons, the material of physical light, are not unconscious perceptions, but unpcrccived stimuli. Likewise, in normal conditions, air pressure is not an unconscious perception, but an unpcrccived stimulus (which nevertheless affects the neurophysiological system). The so-called "subliminal perceptions” are not unconscious perceptions either, but a kind of response to stimulation of which the agent is not aware. These stimuli have a role in determining the conscious state of perceiving: when they change, the state changes as well. However, they arc not perceptible in themselves. Since there arc degrees of awareness, making awareness an integral feature of perceiving enables us to speak about degrees of richness of perceptual content. (D) An intentional state of direct awareness. The notion of “direct” ("immediate”) perception has two primary meanings: (a) perception of objects themselves and not of internal mental mediators which represent them, and (b) perception which is not preceded by mediating processes in which cognitive elaboration occurs. Perception is direct, I believe, in both cases. In the next section I explain why perception is direct in the first case. In the next chapter I explain why it is direct in the second case.6 (E) An intentional state of direct awareness of the environment. The perceptual environment is the varied and meaningful environment we encounter in everyday life. This environment is populated with meaningful objects and events, not with groups of light-waves. Although perception is a kind of state, it is usually directed at unitary meaningful objects and events. Later in this chapter I discuss the ontological status of the perceptual environment and some of its other features. At present I merely wish to point out some of the basic differences between mental percepts (by the dualistic approach) and the perceptual environment (by the approach suggested here). First, the class of attributes which belongs to the perceptual environment is much larger than that of mental percepts. The latter typically consist of secondary qualities such as colors, sounds and pains. The inclusion of qualities other than these is problematic. In contrast, the perceptual environment includes attributes such as edibility, graspability and support, which are hard to classify according to the traditional mental-physical dichotomy as either mental or physical.7 In this case the mental-physical dichotomy becomes blurred to a great extent. Second, the perceptual environment is not contained in the agent’s head; it is the environment in which the agent actually lives. A color is not an internal, individual entity but a property of objects in the perceptual environment. Third, the perceptual environment is not a
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copy or a picture of the "real” physical world. It belongs to a different level of description than that of the physical world. A better understanding of perception may be achieved by considering Aristotle’s distinction between two kinds of actualization: (1) Motion which is an incomplete process (kinesis). As long as this process takes place the end has not been achieved; when the end is achieved the process is terminated. (2) Activity v/hich is complete (energeia). It is self-contained in the sense that it has no external aim or product. Examples of the first kind are building, learning and becoming thin. Examples of the second kind arc perceiving, thinking and pleasure. In the second type the function itself is the end; at any moment it is both completed and happening. Perceiving, in this view, is an ongoing activity which is a complete state at any point.8 Perceiving is complete at each and every moment in the sense that it does not need to await any further development to perfect or complete itself. For instance, when we look around we see whole faces and whole trees. We do not see the left half of the face first and then the right half, only to construct a meaningful picture of the whole face afterwards. It is possible, of course, that our sight may be blurred so we do not sec all the details; this situation is different, though, from seeing half-things. Essentially, Ryle adopts this Aristotelian position. He argues that seeing and hearing, like scoring a goal in soccer, are not processes which start and end: “we cannot ask how many seconds were occupied in the scoring of the goal. Up to a certain moment the team was goal-less; from that moment it had scored a goal. But there was no interim moment at which it had half-scored, or scored half of its first goal. Scoring a goal is not a process, but the termination of one and the beginning of another condition of the game."9 The state of scoring a goal is a state of the team, whereas the processes preceding that state are properties of the individual players. Hence, they belong to different levels of descriptions. For Ryle perceiving is clearly not a final product of a production process. Yet he fails to recognize it as a continuous state, and he rejects the description of perceiving as a state or as an ongoing activity. Unlike scoring a goal, seeing and hearing do have temporal duration. This becomes evident, for example, in perceiving a temporal flow of events. However, temporal duration is not requisite for the completion of a perceptual state. Although it takes the sun's rays eight minutes to reach us, it docs not take another eight minutes for us to perceive the sun. Nevertheless, this complete state of awareness may persist for several minutes. This perception is an instantaneous, complete state of awareness. I should note that there is no inherent conflict between something being both a state and an activity. Activity is a continual state. Perceiving can then be referred to as either an activity or a continual state. When this activity is not actualized, it remains a dispositional state. In the preceding chapter I pointed out two relations between neural and mental states: a causality where neural states precede and produce mental states; and a stratification where the two states are different aspects of the same event. When characterizing perception as a scries of
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static and isolated pictures, it is plausible that each picture is the product of a neural cause preceding it. When perception is seen as a continual state, complete at any point, the neural state should take place together with the perceptual state. The production paradigm which separates the end-product from the processes responsible for its creation cannot depict perceiving. Perceiving is an ongoing state which is not the end-product of previous neural processes, nor made up of separate internal entities. One cannot identify the state of visual experience as the last event in a physical series of events as one cannot simply identify the state of checkmate as the last move in a chess game.10 Similarly, love-making is realized within a physical causal chain, but it cannot be described as a last event in that chain. In Anstotle's approach, as in the one suggested here, the relation between neural processes and perceiving is not cause and effect, but rather accidental identity. Perceiving is not separate from the neural processes. Perceiving occurs when those processes arc organized in a specific way. We can conceptually distinguish, but not actually separate, neural and perceptual states. If perceptual content consists solely of distinct and isolated entities, then the relational properties between these entities are not a part of the perceptual content. In the traditional approach temporality is not a real perceptual property: perception is considered timeless, a scries of static snapshots. This contradicts our everyday experience and empirical research. In my approach relational properties constitute perceptual content. Instead of using the static images model, I use a flow model. In this model the temporal succession of events is a fundamental dimension of perception and the perceptual system deals with integrated complex events. It is artificial to cut continuous experience into isolated snapshots. If perceiving is a continual state (or activity) which is complete at any moment, it can account for continuity which persists through change and the meaningfulness so typical of perception.11 This description of perception is consistent with the description of the mind in the last chapter. Biological adaptation, also a continual state, can be compared to the state of perceiving. Adaptation should also be explained by referring to several levels of description, such as the chemical and the biological. The tost level is an analysis of chemical interactions taking place in the organism s body. This level describes adaptation’s supportive basis, yet the term adaptation" itself is absent from the description. This term is found only in a broader context which includes functional aspects of the interaction between the organism and its environment. From a chemical standpomt adaptation (or its supportive basis) is a causal process of chemical changes. From a biological standpoint adaptation is a continual state. As in the case of perception, adaptation resides in neither the external physical world nor in the organism itself. It is a relational state o a system which presupposes the existence of an organism and its biological environment. Berkeley, among others, likens perception to language. Isolated nsations, such as individual colors and sounds, are compared to letters;
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their combinations make them meaningful. I reject this view because I reject the existence of an initial perceptual stage consisting of isolated, meaningless sensations. If one insists on using the perception-language analogy, letters should be compared to physical states of the brain. These states, like letters, belong to a physical realm which differs from the meaningful perceptual (or linguistic) realm. Moreover, letters do not produce linguistic meanings since meanings include "stuff" not found in letters themselves. Nevertheless, letters are a supportive basis for linguistic meanings. Similarly, perceptual meanings contain "stuff’ not found in physical states of the brain. Therefore, if these physical states are described as the sole cause of such meanings, we have an effect without a cause. States of the brain, however, are a supportive basis for perceptual meanings. This comparison can continue: although one may find a direct mapping between linguistic (or perceptual) meanings and letters (or states of the brain), the former are not identical with the latter and they are not part of them. In summary, one should distinguish between neural processes and the experience of perceiving. The processes are only a supportive basis for perceiving. Perceiving is not their finished product. Therefore, we should not postulate the existence of perceptual entities at the termination point of the neural processes. The category of "process" best describes the neural mechanism, whereas perceptual experiences are best described by the category “continual states.” While the neural processes occur in the perceiver, perceiving itself is a relational experience happening in both the perceiver and the perceiver's surroundings.
(3.2) The Direct and Meaningful Nature of Perception According to perceptual dualism mental processes construct the perceptual environment from meaningless sensory materials. Usually, the mind initially constructs one “atom” of the perceptual environment and then, by way of computation, inference or association, constructs other "atoms” one by one until a whole meaningful environment is completed. This model is consonant with the picture of the mind as imprisoned within the brain, busily interpreting meaningless neural signals. In addition, this model is compatible with the assumption that intellectual processes, such as computations and inferences, arc the basic cognitive activities in perception. This model breaks down the meaningful environment into simple and isolated entities; these are the entities with which the intellectual system is equipped to deal. Once we replace the inside-outside dichotomy with the stratification approach (which frees the mind from its internal prison), and deny that computations and inferences arc the basic perceptual activities (see Chapter 5), the dualistic approach no longer makes sense. We no longer have to assume that we first sense meaningless atoms and then interpret them to be meaningful perceptual objects. As Dilthey argues, “Mental life does not arise from parts growing together; it is not
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compounded of elementary units; it docs not result from interacting particles of sensation or feeling; it is always an encompassing unity." Similarly, Wittgenstein argues that “When we first begin to believe anything, what we believe is not a single proposition, it is a whole system of propositions. (Light dawns gradually over the whole.)” 2 Indeed, we experience continuity even with stimulus discontinuity. For instance, eye movements provide a continuity of the scene we sec, not static snapshots of it. Turning around produces a continuous field, not an impression of different scenes. This feature of continuity is compatible with the assumption that perceiving is a complete, ongoing state; it is a unitary form of awareness. Perceptual content, like a point on a map, is not an isolated, discrete unit. It depends upon, and is realized within, a whole system of coordinates. The content of a perceptual experience, like the content of a belief, can often be compared to a whole proposition. We do not see isolated points: we see an organized, meaningful event. We see that such and such is the case and categorize it as belonging to a certain type. In this regard, seeing is "secing-that.”13 The organized, meaningful nature of perceptual content can be exemplified by referring to the color spectrum. For years this spectrum was assumed to be structureless and meaningless: a spectrum divided arbitrarily into different color categories. For instance, cultures have differing numbers of color terms: whereas some have as many as 4000 color terms, the Dani tribe in New Guinea has only two (one for dark colors and another for light). The challenge to this assumption claims that color perception determines language and not vice versa. 1 hat is, the perceptual structure of the color spectrum determines our basic color categorization. One experiment which suggests a structured, prototypic arrangement for the color spectrum is the following: People from 2 different cultures were shown colored chips from the entire color spectrum and were asked to point out the chip best exemplifying cac basic term; the subjects made similar choices. According to this research not all distinguishable hues have equal psychological status: the positions occupied by the basic colors are more central than others and thereby they constitute the structure of the color spectrum. I his explains why, despite the human visual system’s ability to distinguish 7.5 million hues, human languages have a limited number of color terms and among them only a few are basic terms. Further research shows that this structure has a special effect on human beings. Basic colors arc universally more codable than nonbasic colors, they arc more easily remembered and learned, children prefer them to nonbasic colors, and they arc reference points for color categorization.14 Research in other perceptual and psychological domains has obtained similar results. Studies on learning suggest that when an animal learns about its environment it does not associate equally the events it confronts. For instance, rats continue to associate certain tastes with illness even after long delays of reinforcement, but they resist associating tastes with foot-shock.15 The environment perceived and known is not
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an arbitrarily connected mass of events. It is structured and meaningful. In performing their various activities, agents take account of the structure of the environment. Therefore their cognitive tools should consist of structured categories, like prototypes, and rules of organization, like schemas.16 Although we may make our perceptual environment more meaningful and organized, at no point is our environment completely meaningless and unorganized. liven the simplest creatures attune themselves to the uniformities in their environment which are important for their well-being. An intelligent being presupposes a highly structured environment. What happens at one time and place must relate to and contain information about what has happened or will happen elsewhere. In the approach suggested here there is no need to postulate an intermediate, meaningless sensory stage since we assume that the perceiver encounters a meaningful perceptual environment. Perceiving is an awareness of meaningful content, so there cannot be meaningless perception. My approach toward perception is similar to Kant’s epistemological approach, which attempts to solve the philosophical problem of the difference between the meaningless and unorganized “stuff’ existing independently of the agent and the meaningful, organized world the agent lives in. The empiricist’s solution to this problem postulates the existence of a process of associations from past experience. These associations add meaning to the meaningless materials presented to the agent. The rationalist’s solution postulates principles of understanding (that somehow correspond to the regularity of the external physical world) which are supposed to do the same job. These solutions arc unsatisfactory because they do not explain how the postulated process, or principles, actually fulfil their task: How can completely meaningless materials become meaningful? Kant claims that the empirical subject does not encounter the meaningless materials. T he empirical (phenomenal) world in which the empirical subject lives is already organized and meaningful because it includes contributions from the transcendental subject. Each object in our experience (empirical world) "must conform to the constitution of our faculty of intuition" and to our a priori concepts — and this makes them meaningful; only by presupposing them "is anything possible ar object of experience."' T his approach has no need (on the empirical level of description) to postulate the existence of a temporal process that converts meaningless materials into meaningful objects. It docs present a need to distinguish between different levels of description for the world (empirical, transcendental, and thing-in-itself) on the one hand and the subject (empirical, transcendental, and the suhject-in-itself) on the other.18 The empirical subject does not need to convert the meaningless "stuff' of the thing-in-itself into meaningful objects because the subject never encounters that “stuff.” (Inly when discussing what constitutes the empirical world as a whole docs it become necessary to refer to the relations of this world to the transcendental level and to the thing (subject)-in-itself.
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ronsimSnTIUti0n ccntral ProbIcm of ‘he dualistic approach, a.mcan!nBfu> Perceptual environment out of meaningless level of!C?^S’.,S Slnular: ,hc perceptual environment exists on a different Son Jent P n fromrthat Of thc Ph>’sical "°rld- ' he perceptual mean?nHe« nK°n-S1S S °f !PcanulPfuI objects and events, not of imnncnH nn tE^S1C^ stlmub- Hence, meanings do not have to be n k i cnvironmcnt because they are essential features of it (as 2XnrP * k Og?J drCady contends)- Gibson’s ecological approach to S Hnn? b^Sed °" ,hc,samc understanding: “ The world of physical real,'tv a n?r c°nsist meaningful things. Thc world of ecological mathem "bat We Percc‘vcd were the entities of physics and me eernn^ ’ rnc?nin8s. )vould have to be imposed on them, nut if what P iv e are ic entities of environmental science, their meanings can t S' C,5h Accordingly, Gibson argues that “Ever since Descartes, ps\ , ogj as been held back by the doctrine that what we have to perceive is c physical world that is described by physics. I am sugges mg a "hat we have to perceive and cope with is thc world const ere as he environment." Gibson claims that we perceive thc ^ound”2®^ "C h'e Md “lfer the 'vorId of Ph-vsicist' not thc other way
T° explain the meaningful character of the perceptual environment, son rcso s to thc novel notion of “affordances.” Affordances are propemes ot the environment that are meaningful in reference to an mdividuak The affordances of the environment are what it offers the anim , v a i provides or furnishes, either for good or ill.”21 The Pr^eP,cc.a suPPorting surface at approximately thc height of an mdividual s knees affords being sat upon. Gibson's use of affordances is e. 0 □°k-r’SCabng and species-specific properties (such as support, grasping, c i ty, etc.). But one can also speak of culturally derived or aufus (meanings), and even of individually derived affordances. S nnr nn,iei md,v,dural agent who does the perceiving, thc features that rP^C C ,0 may influence perception just as
In light of Gibsotn'sPw °f pcrccptual ,?’caninK|.. different levels in describht *S P?S51bIc 23° dls)t'nSu.,sb ,scvc.ral Ihev are- tai the mm,.r 8 the Perceptual input.23 In the visual realm input for the whole phyXloricT0'’ ’ C'’ 3 S‘rCam °f ‘i’"5’ (b) 1 over space and time and ‘t’ Pa“CmS extcndcd objects and events Onlv th mp for lhe pcrcelvcr' l c” meaningful meaningful perception of the third'? i mn' ^T' consideration depends on h i, r h Thc urut °f stlmulatlon undcr By assuming the existence nffk °f scnsitivi‘y we concerned with, of properties that can belnno . T°nd sta8C’ Glbson expands thc types attempts to overcome thn • r° ’he proxirnal stimulus. In this way he le mformational gap which in the dualistic
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approach is assumed to exist between the stimulus source (the object) and the proximal stimulation. This docs not, however, eliminate the gap resulting from the influence of personal contributions on perceptual content. Instead of thinking that the perceptual system encounters isolated atoms from which an object is created or imagined, we can assume that at a certain level of description the perceptual system is sensitive to that object. An input for the perceptual system must be meaningful for that system. For this reason humans do not perceive electromagnetic waves, subatomic particles, retinal images, neural impulses, or unorganized masses of sensations. The physical system underlying the perceptual activity involves energy absorption by receptor organs. But we do not perceive energy qua energy: we perceive organized, meaningful objects and events. We do not perceive light energy of 505nm, we perceive a green object. Considering, however, that the physical and perceptual realms are different levels of describing the same world, we are, in a sense, aware of the world described by physics while being aware of our perceptual environment. Like Kant’s view, my view considers the direct and meaningful na ture of the perceptual environment possible only because the organism itself is an essential constituent of this environment. The perceptual environment is a meaningful environment for an organism because the organism’s activity takes place within it. This environment is relational: it presupposes relations to an organism. Accordingly, speaking about that environment in a context void of any reference to an organism is meaningless. The relational nature of the perceptual environment is a price one has to pay for the meaningfulness of that environment. The following discussion illustrates a direct encounter with meaningful content. (In this section I refer to the first meaning of direct perception: perception of the objects themselves, and not of internal mental mediators representing them. The second meaning, that excluding mediating cognitive processes, will be discussed in the next chapter.) After reading one of Russell's books I changed my opinions and so I can state that Russell’s opinions directly influenced my own. In analyzing this direct influence it makes no difference that Russell wrote his book before I was born, that he died before I read the book, or what the most adequate theory is concerning the neural process underlying my reading of the book. When discussing the intellectual relation of Russell's opinions to mine the physical medium transmitting Russell's opinions is an irrelevant factor. A physical entity cannot be a mediator in an intellectual relation because it belongs to a different level of description. In order to speak about mediation, or indirectness, the mediation must be on the relevant level of description. The same is true for a conversation between two people. In an analysis of an exchange of views, any reference to the atoms or light waves involved in producing that conversation is irrelevant. In the analysis of a meaningful conversation between two people, neural mechanisms are not factors because this level of description already
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presupposes their existence. Therefore, they cannot be regarded as epistemic mediators. A chess match between two people is a direct match whether the two players sit in the same room or play by phone or by mail. The visual and auditory' processes underlying the game are not mediators because they do not belong to the relevant level of description. They arc like scaffolding which will be disassembled after use. The grasping of a certain meaning is not direct in the case of misunderstanding which is corrected by presenting another meaning. The grasping is mediated by the presentation, which is relevant by virtue of its being on the same level of description as the understanding. Just as physical processes are not factors in analyzing an intellectual relation, they are not mediators in the perceptual realm either. Physical waves and atoms have, of course, a causal role in the emergence of perceptual states, but they do not mediate the perception of the various objects. Although they are not perceptual mediators they do constitute a physical medium; but “a medium is not a mediator; it is a transducer.”24 Perceptual (like conceptual) directness is different from causal directness. To take another example, when I watched the president’s speech on television yesterday, there was a direct relation between the content of his speech and my beliefs, despite the complicated electronic devices facilitating the connection between us. In this case it is entirely appropriate to ask if the president directly influenced my beliefs or if he directly irritated me. The mediating electronic and neural processes are not relevant to the level of description analyzing the influence of the president's speech on my intellectual beliefs. However, I saw the president indirectly through watching the picture on my television screen. When we describe the relation between the president’s opinions and my own, the television picture is not an intellectual mediator because it does not belong to the intellectual level of description. The television picture, however, is a visual (or perceptual} mediator since I see the president through it. In this case, the picture is on the relevant level of description. In determining the directness or indirectness of perception the physical distance between objects and eyes, or the medium presenting the information, are not relevant factors. Similarly, we do not say that internal ideas are the immediate objects of love or jealousy, or that these emotional attitudes are not direct, because they are mediated by neural processes. Emotions can be directed at entities having no physical existence. One can (directly) hate a person who died a long time ago. The lapsed time, like the neural processes, is not a relevant factor in determining the directness of the emotional attitude. The above examples illustrate the compatibility of direct relations on one level of description with complicated and mediating processes on a lower level. Mediating processes on the lower level arc not necessarily an indication of mediating processes on the higher level because a higher-level entity consists of many lower-level entities. For instance, on the sociological level the socialist movement has directly influenced the development of various European societies. On the psychological level
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this influence has taken place through the complicated and mediated activities of many people. This shows that mediation on one level is not necessarily mediation on another. Likewise, perception is direct awareness of the environment despite the complicated and mediated physical processes underlying it. I,ike reading, perceiving is a direct form of understanding.25 The existence of perceptual illusions could be claimed to contradict my contention that perception is direct. This vzill be discussed in Chapter 5. I will show that the basis for perceptual mistakes is not a correspondence between perceptual pictures and physical entities, but a certain relation within the perceptual environment, namely, perception under normal conditions. I will argue that the existence of illusions does not prove that perception is indirect. Notwithstanding my objections concerning a non-epistemic sensory stage that precedes perception, instances can be cited in which the perceptual content is closer to the dualistic sensory given. These would include, for example, the sort of perceptual content characteristic of lower-level living forms such as viruses and amoebas; of fetuses during the first weeks of gestation; of people with perceptual defects (e.g., blind persons whose sight has been recently restored); of vision undertaken in conditions of almost complete darkness; and of perceptions under conditions of sensory deprivation artificially induced in a laboratory when only an isolated stimulus is presented to the subject. The existence of thtse primitive perceptual states does not mean that our daily perception has a non-epistemic sensory stage preceding the epistemic stage of perception. In these cases the perceptual content is more immediately related to the physical stimuli. That is, its creation involves a less complex cognitive activity and the cognitive system as a whole plays a less crucial role. In this situation there may be a greater correlation of the physical stimulus with the perceptual content. Thus, colors and shapes are properties more immediately related to the physical stimuli of vision than sadness is, because perceiving sadness consists of perceiving colors and shapes in addition to other features. From a cognitive point of view, perceiving sadness may be more complex.26 The pcrccivcr's perspective may play less of a role in determining the perceptual content of colors than in determining, say, the content of multistable stimuli such as reversible or ambiguous figures. In this sense the content of the former may be closer to the dualistic sensory given. (Illis claim too is problematic. A change in one’s mood, or another change in one's perspective, may result in a change of the color perceived but not in a change in perceiving a certain ambiguous figure.) Even if diminishing the role of one’s mental framework is possible, it does not mean that a mental state exists in which this framework has no role whatever. For the same reason the possibility of eating less does not imply a state in which one can survive without eating at all.
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(3.3) The Intentional and Feeling Dimensions in Perceptual Experiences As mentioned before, the mental realm has two basic dimensions: feeling and intentionality. Intentionality refers to the subject-object relation, feeling expresses the subject's own state. The feeling dimension in perception is often termed "sensation." In the dualistic approach sensation is not just one aspect of the perceptual state, but a separate stage preceding it. Reid reused the dualistic description of the sensation-perception distinction by regarding sensation (or feeling) as a simultaneous aspect of perception, not as a separate stage preceding it: “The external senses have a double province — to make us feel, and to make us perceive. They furnish us with a variety of sensations, some pleasant, others painful, and others indifferent; at the same time, they give us a conception and an invincible belief of the existence of external objects.”27 My stand is similar to Reid's. I consider the feeling dimension (or sensation) to be an aspect of a complex perceptual experience. The same feeling, say, a painful one, can accompany' different perceptual states or different intentional perspectives. Feelings arc contingent accompaniments to perceptual (and other intentional) states; they are not essential to perceiving. The feeling dimension is to a large extent noncognitive since i basically does not have cognitive content; it does not claim anything. This is different from the dualists’ view that the feeling dimension is unaffected by one’s personal characteristics and circumstances, us because a feeling is influenced by mental characteristics, this ocs,n0 imply the existence of cognitive content in the feeling as I 1 nB about a pleasant event may reduce my present pain, but this does no imply that pain is thinking or that pain includes the same cogni ive content as is present in thought. Raw feelings may be influence y complex mental states which consist of cognitive and eva ua ive components, without consisting of cognitive and evaluative components themselves. , The feeling dimension in perceptual experiences, and elsewhere, is experienced as if the feelings are "inside” us whereas the intentiona dimension in perception expresses a reference to external objects. Since I reject the internal-external distinction in describing the dillcrcnce between the mental and physical realms, I believe that such feelings should not be described as internal but as expressing the agent s own state whereas the intentional dimension supplies information about the agent’s surroundings. Pleasure, pain, excitement and relaxation arc a few examples of the feeling dimension in perception. When one is viewing something beautiful, one’s complex experience involves something beside the beautiful content, namely, pleasure or (as Marcuse noted) a feeling like that involved in astonishment. Similarly, when looking at something frightening one may feel chills. According to Aristotle feelings of pain and pleasure always accompany sense perception.28 I would formulate this idea differently. Each perceptual experience, like other mental
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experiences, has a feeling dimension, but at times this dimension can be neutral in regard to pleasure or pain. This is the case in many perceptual experiences. If, for example, I look at my desk, I am hardly aware of the feeling dimension because it is fairly neutral. It could be claimed, in these cases, that the feeling dimension is absent. I would say, though, that in such cases the feeling dimension may be neutral regarding the painful-enjoyable continuum, but not regarding the tenseness-relaxation continuum. Contrary to perceptual experiences, emotional experiences which are neutral on the painful-enjoyable continuum arc rare. The greater the sensitivity of the person, the fewer of these cases exist. In a sudden change of the agent’s situation the feeling dimension is quite obvious. Hacker describes various differences between the feeling and the intentional dimensions in perception: (1) Unlike the intentional dimension, feelings have a location in the agent’s body (global feelings may be said to have a global location, that is. they are located in the whole body). (2) There is no organ of feeling in the sense that there is an organ of vision or of hearing; thus we do not feel pain witA our hand but in our hand. (3) Feelings have degrees of intensity, but not the degrees of clarity which arc typical of the intentional dimension. (4) Since feelings express the agent’s state, they are more closely connected with the agent’s behavior. (5) One cannot be in error or doubt about one’s feelings. (6) To have feelings is not to exercise a faculty; there are no skills involved in having feelings, so that there is no way in which we can learn to have more accurate feelings.29 Within the intentional dimension itself one may distinguish between the intentional content and the intentional form (or the intentional mode of presentation). The intentional form is what distinguishes the state of seeing a certain thing from touching (or thinking about) the very same thing. This form expresses the way by which the intentional content is conveyed. The intentional form has no content, but it shapes (so to speak) the intentional content. There are then two non-belief (or non-conceptual) components in complex perceptual experience: the intentional form and the feeling dimension. The feeling dimension may be regarded as part of the broader mental experience existing at the moment of perception, while the intentional form and the intentional content (perceptual belief) arc part of the more limited perceptual state. The existence of non-cognitive components in the perceptual experience does not deny the epistcmic nature of perceptual experiences. Such a denial needs to establish that only these components exist in perceptual experiences. 'ITic impression of the receptive, or compulsory, nature of perception may be regarded as belonging to the intentional form of perceptual experiences. Unlike thinking and imagining, where we are aware of our ability to choose the content, perceiving leaves the impression that the content is imposed upon us. Perceivers can consciously choose whether to apply their perceptual capacity, and to what aspects of a given content to refer; but generally perceivers cannot
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consciously change the perceptual content. (As 1 will argue in the next chapter, the receptivity of perception is not contrary to its constructive nature.) The impression of familiarity in memory may also be regarded as belonging to the intentional form. , Is there any difference among the senses regarding the feeling an intentional dimensions? In sight there is a clear distinction between c intentional object and the feeling of the agent seeing that . c pcrceivcr is aware of the visual qualities, without “possessing cm. When seeing a green tree we do not perceive the green or the tree as ou property. Despite the perceiver’s role in the presence of visual (and omer perceptual) qualities, all types of visual qualities arc perceived Per“*.ve properties of the objects themselves and not of the pcrceivcr. tn tms sun such there is no difference between seeing secondary qualities, sue , as as colors, The and seeing primary qualities, such as motion and 1Bur • , in other objectification occurring in sight is similar to what occursi intentional states. In thought, memory and emotion the con regarded by us as a property of the intentional object, and no o • golden mountain, which I am thinking about now, has no p existence; but the gold upon it is still regarded as a prop y mountain itself. Similarly, beauty is often perceived as a prop y ^ perceived object, although its dependence upon the suojee is obvious. . . , ,L„r_ no Tactile objectification is more primitive. Unlike sig , clear separation between the perceptual state and the objec ■ at. Tactile qualities appear to exist both in the pcrceivcr . , as a environment. On touching a cold object, the cold is P Hties property of both the object and the pcrceivcr. These ta m achieve the first stage of separation between cognitive agen . ‘ of surroundings only to a certain degree; hence they have a .. JLivc” intentionality. (The use of the term “feci" rather that P0^ regarding tactile qualities is an indication for this.) Feelings s rcEarded pleasure and tickle do not achieve even this stage, so t CY nanitivc as merely properties of the pcrceivcr. They do not have • . .:or)a] relation of being "about something,” therefore they arc no these As previously indicated, the self-awareness (or perceptio } feelings is intentional. When I am aware of my toothache or > this awareness is an intentional state directed at the ache or Despite the similarity between tactile qualities and pleasure and pain, these feelings are also an clement in t ic co p experience of perceiving tactile qualities. I hus, it makes sense ■ whether a cold feeling is painful or pleasurable. Likewise, psycholog research indicates a difference between two aspects of taste experience, perceiving sweetness and feeling pleasure. Studies show that sweetness and pleasantness of sucrose solutions (and sweetened food) conform to different functions. Sweetness rises with concentration, whereas pleasantness first rises and then decreases.30 Tactile qualities and feelings also differ in the fact that unlike feeling, touch is a trainable skill.
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I’hc “Tactile Vision Substitution System” can shed mure light on the various types of intentionality involved in perception I hr. lyion, originally developed for the blind, involves the transmission of a visual image from a television camera to the skin on a person’s back via an array of vibrating pins ITiis device can communicate various -j,a'ial properties of objects, but not colors \ blind man who made ir.i: of ’itsystem tells that at first the sensations seemed to be on his back. J-ater the sensations appeared to him in two-dimensional space which did r.'ri seem to be “out there." By this time he became less and less aware that vibrating pins were making contact with his skin. 'I he objects came to have a top and bottom, as well as a right and left, but they had r.o depth.3 /Apparently his new cognitive system developed from -imp?; feelings to the intentionality typical of tactile qualities. He could r.'.t attain the intentional separation typical of sight, though. The case of blind people who have had their sight surgical?, restored is similar to the previous example. These people do not localize their visual impressions, they see colors in the way others smell an odcr The simplest mode of color vision (as classified by the Optical Sori;*... of America) also exemplifies a primitive type of intentionality. In themode of vision, film color produced under artificial conditions makes the agent perceive a textureless, two-dimensional expanse of color n:‘. identifiable as the color of any surface, or as being any particular distance away.32 Under these artificial conditions the degree of intentior.cl.rtypical of vision is not achieved. Hearing, smell, and taste occupy a middle position, between sigr: and touch, on the scale of intentional separation. In taste, as in tcuri* the perceptual qualities seem to be properties of both the object and the subject. In smell and hearing these qualities are already not proper:.cof the subject, but they are perceived to be properties of the object the medium. Only in vision is there the developed intentional scp. r.f r-. in which the perceptual qualities are merely properties of the object The different perceptual erodes of intentional objectific.it w’ connected with the different err. mt of information conveyed bv . . sense. Only the rich inf m. t; r. . d in sight enables the sub .x form a presentation f ■. perceptual object. I lie itch ' • information is to a 1 .-. • r.t r lund.mt lor immediate ■> purposes but it allows the formation of a cognitive (or intrn presentation of a ..? ... ; . ri object I lie other .11 ■ ■ ■ . •> impoverished inf rm/: r. :r i. ..‘ .'.hi11 tit di.1 various aspect' vf .upu> ill it III III ■ >. complex expert er. or
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sensory dimension constitutes the entire experience. This may happen when the feeling dimension is very intense. In these eases, there is a separate sensory stage (as perceptual dualism assumes), but this stage docs not precede a perceptual stage since there is no such a stage. The various types of objectification, or intentional separation, in the visual and tactile realms have been subjected to different interpretations. Aristotle made no significant ontological distinction between the perceptual environment and the physical world, so in his view the properties common to the organism and the environment (and hence to the physical world) have the most objective status. 1 hese properties arc the tactile qualities composing bodies. Regarding the qualities of sight, hearing, and smell Aristotle raises questions concerning their objective nature. Aristotle attributes the greatest biological importance to the sense of touch probably because it is connected with nutrition and qualities such as cold and" heat which have important survival value. However Aristotle claims sight to be of the greatest cognitive importance since sight, “most of all the senses, makes us know and brings to light many differences between things.” Hence, sight is more authoritative than touch.” Whereas touch is an important means of preservation,” sidit, hearing, and smell “serve for the attainment o a higher perfection. , In many modem theories of perception, touch has not on y a greater biological importance but a greater cognitive importance as we: . This is because touch is considered to be direct whereas sight an other senses are mediated. Berkeley takes this position. Assuming tactile qualities exist both in the percciver and in the environment scjcr“ to support the direct and undistorted manner of tactile pcrccp 10 Therefore, Berkeley claims that touch educates vision, adding meaning to the initially meaningless visual sensation. He assumes that an 1 an discovers that an object is a distinct, three-dimensional body only y touching it. This leads to the conclusion that touch has the grea c cognitive validity. , ... Current psychological research confirms Aristotle s posi ion. subjects take sight to be more authoritative. When their touch conveys information in contradiction with their sight, the visual information determines their perception. By simultaneously viewing through a lens that reduces the size of an object or distorts its shape, and grasping at t ie object, contradictory information from vision and touch is presented. Most of the subjects were not even aware of the conflicting information. Their unitary perceptual experience agreed closely with the illusory visual experience. Sometimes, when the conflicting information is noticed a change in touch perception itself takes place, making it consistent with the visual perception, furthermore, research on five-month-old infants has found cross-modal transfer of form from vision to touch, but not from touch to vision.36 These results may seem surprising in light of the plausible assumption that the sense of touch evolved before the sense of sight and is of greater biological significance for survival. However, the studies cited above compare the perception of properties that are
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common to touch and vision (e.g., size and shape), whereas the tactile properties essential for survival (e.g., properties connected with nutrition and those of heat and cold) arc typical only of touch. In this regard, the more essential nature of touch is not in conflict with the above findings. I also reject Berkeley’s assumption that touch is direct whereas vision is indirect. If, as I have suggested, we take a medium to be a transducer and not a mediator, touch should not be regarded as more direct than vision: the “transduction of information through air and space makes perception no more indirect than the transduction of information through peripheral nerves.’’37 The higher authority of sight docs not indicate the more objective ontological status of visual qualities. Both visual and tactile qualities are relational in that they presuppose the existence of a perceiver. The higher authority indicates only that sight transmits more information than touch. This is compatible with the more developed intentional separation of subject and object found in sight.
(3.4) Perceptual Knowledge
Perceptual knowledge is often described as relative. I consider knowledge to be relational, but not necessarily relative. Often no distinction is made between relational and relative; consequently a lot of confusion is created. Ix:t me try to clarify the issues involved. The relational-elemental distinction concerns the presence and absence of relations. Something relational is constituted of relations. Its opposite, “elemental” or “fundamental,” means that something is capable of existing independently of the relations into which it enters. The relational-elemental distinction can be applied to the ontological as well as to the epistemological realm. Ontologically, whatever ultimately exists may be assumed to consist of either elemental entities or relational properties. Similarly, in the epistemological realm, whatever is actually known through perception may be claimed to be either elemental entities (e.g., sensory atoms) or relational properties (e.g., motion and change). Physical and sensory atoms are obvious examples of elemental entities. Relations of any type are relational properties. Most states of affairs apparently consist of both elemental and relational properties. 'They may be regarded as consisting of elemental entities at one level of description and as expressing relational properties at another level. A chair is an elemental entity when we talk about furniture; but in nuclear physics what we call a “chair" is discussed in terms of a relational state composed of different elemental entities. For our purposes, something will be characterized as relational if it consists of relations on the relevant level of description. For instance, if we see an object in motion, rather than in successive static pictures, then we sec relational properties. The relative-absolute distinction is an epistemological distinction regarding the nature of a certain claim (or predicate). A relative claim is one whose context is not specified, so that its validity and meaning are
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indeterminate. The claim "Adam has one” is relative. "One" in this claim is a relative predicate. Absolute is the opposite of relative. An absolute claim is one whose context is more or less specified, so its validity is more or less determinate. The claim “Adam has one brother” is an absolute claim because "brother" specifics the context of discussion. Generally speaking if, in relation to R, A is X, and in relation to S, A is Y, then X and Y arc relative predicates of A. But “A is X in relation to R” and "A is Y in relation to S” arc absolute claims.38 Relativity involves an ambiguity concerning the validity and meaning of our claims stemming from the nonspecification of the relevant context. Isolated words are often ambiguous since they can be used in different contexts with different meanings. Accordingly, their meaning is indefinite and we are left with incompatible diversity. f Difficulties arise in specifying contexts: there are various degrees ot specification and different kinds of possible contexts. One may argue tha although in my view the assertion “Dean is twenty years old shorn e regarded as absolute, the term "twenty years old” is relative since it oes not fully specify the context. It is not clear whether it means exac y twenty at this moment, or more than twenty years but no more an twenty-one. Moreover, a year may stand for a solar year (the peno required for one revolution of the earth around the sun, approxima c y 365.25 days) or a lunar year (twelve intervals between new moons approximately 354.3 days) or a cycle in the Gregorian calendar ( 366 days). A more detailed specification of the context can near y w y make the claim more precise. These difficulties arc also ypic linguistic ambiguities. Our language, in many cases, is ambiguous r respect to specificity and meaning. . , , . „«• It is possible, however, to distinguish between indcterrru Y meaning from indeterminacy of precision. Claims can always c more precise, but this does not usually mean that the less precise c were meaningless. Only some kinds of imprecision, or ac specification, create the incompatible diversity resulting in meaning! claims. The claim “Dean is twenty” gives no ideas regarding the mca g of “twenty” in this context. Yet, saying “Dean is twenty years o 1 meaningful claim; it gives a general idea about its reference. 1 he re er may be imprecise and have unclear borders, between 20 and 21 years an between a year of 354 days and 366 days, but in most contexts sue imprecision is not important. In contrast, the claim “Dean is abou to 80 years old” is in many contexts indeterminate regarding o i precision and meaning. Here the indeterminacy concerning precision becomes indeterminacy concerning meaning as well. However, even in this case the above claim is meaningful to a certain extent if my interest is limited to whether Dean is a child or an adult. Although there are difficulties in fully specifying the relevant context, some sort of specification is always available. Linguistically the crucial point is if the specification in question allows a meaningful communication. This would indicate that the ambiguity has been eliminated to a certain extent. The same holds for the ambiguity of
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Illative claims. The cognitive claim: " I he length of the table is 2" is relative since there is no .specification of the context which “2" refers to. Illis incompatible diversity prevents us from understanding the claim. Once the context is specified (say in meters) the claim is no longer relative: we can now grasp its meaning and examine its validity. An explicit specification of the context is not always a simple task, but the existence of meaningful communication and common understanding bear witness to the existence of at least an implicit specification. I characterize relativity as the nonspecification of the given context. Indeed this characterization, in light of Einstein’s view, makes traditional claims concerning mass and velocity relative ones. In Einstein’s view mass and velocity necessitate specification of a reference to inertial frameworks. This is one more parameter than was formerly thought to be needed. As long as this parameter is unspecified, claims about mass and velocity are indeterminable. T he traditional claims are relative not because they are relational, but because they fail to specify a relevant framework. When this specification is made, the traditional claims are no longer relative. The common confusion of “relative” with “relational" should be avoided. Relational is being related to something, whereas relative is a relational claim whose context is not specified. The essence of a relative claim is not its relation to something else, because there are many kinds of relations that have nothing to do with relativity. Many physical objects are also related to something else but they are not relative since they do not make any claims. Relativity is an epistemological relation. "Relative” and “diverse” are also not identical because many types of diversity have nothing to do with relativity. For example, although a variety of stones exist in the world, a stone is not a relative entity. Although "relative” is a kind of diversity, the two cannot be identified. In relative claims, where the context is not explicitly or implicitly specified, diverse anti incompatible conclusions are possible. Whereas "relativity” implies incompatible diversity, diversity does not necessarily imply relativity. Relativity is derived from indeterminacy, not from diversity; it can, however, cause an epistemological diversity. The common identification of “absolute” with “universal" should also be rejected, as should the identification of "relative" with “particular.” An absolute claim is a fully determined claim in its context, but it is not universal or invariant in different contexts. The claim "T om’s height is now 1.8 meters" is an absolute claim, but it docs not imply that Tom's heiglit will always be 1.8 meters. Returning to perception, I suggest that perception is relational and usually absolute. Perceptual dualism tends to assume that the "proper" perceptual content is elemental. Berkeley’s minima sensibilia and Hume's sensory atomism are examples of this tradition. An extreme formulation of this stand is found in Stewart's contention that the mind perceives only one sensory atom at a time (sec 1.4). Gestalt psychology' has clearly shown this atomistic (elemental) characterization to be false, and perceptual content to be constituted by relations. I will not expand on
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the findings of Gestalt psychology beyond mentioning only a few empirical findings which clearly demonstrate the relational nature of perception. In stabilized image experiments the retinal image can be made to move along with the eye by using contact lenses that move with the eye. This achieves image stabilization.-After the image is stabilized on the retina it soon fades and disappears. T hese experiments show that the visual system responds to a change of stimulation (which is a relational property), rather than to the mere presence or absence of stimulation. Since stabilized images do not change with time, and hence do not have relational properties, they cannot be seen.’’9 This also holds true for color perception: "Color disappears quickly in the stabilized image of a co orc figure. In a field composed of the three primary colors, the red, green an blue hues disappear to leave a colorless field of three different degrees o brightness. These briehtness differences also disappear with time, u i is the color that goes first.”40 The same results were obtained when a uniform color filled one's field of view (Ganzfeld). In this expenmen , owing to lack of relational properties the color disappears and cc0 dark gray. These phenomena indicate that “the eye sends the rain information about chances in light across boundaries with area no change is reported bJing filled in by the brain as homogeneous Contrary to perceptual dualism, relational properties are c perceptual content; they are not an arbitrary addition to give content. Despite the relational nature of perception, perceptua1 are often not experienced as relational because one of the re a ■ as constant, that is, as irrelevant background to the given 1g ■ other types of cognition, perceptual knowledge is made up o An isolated point can be neither perceived nor known. Cognition is relational not only in that its objee s m certain relations, but also in that it presupposes some rclati , agent’s cognitive perspective (which can be termed c P framework,” "paradigm,” "frame of reference,” ‘constellaton of presuppositions," “a priori principle,” etc.). I he agents perspective is determined by various factors: biological makeup, . religion, language, economic and social factors, personal history, < ■ on. Each factor may have a different weight in different circums • ■• All forms of cognition are related to, or presented from, a cer ain perspective. This type of relationality is the essence o an epistemology according to which the knower organizes, an even constitutes, what is known. The agent’s cognitive perspective becomes a parameter in determining the meaning and the truth of the agent s claims. Determining the real color of our surroundings should take into account the color of the glasses we are wearing. This type of relationality indicates the constructive nature of cognition in general, and perception in particular. I have argued that the relative-absolute distinction is an epistemological distinction between relational claims whose context is specified (absolute claims), and relational claims whose context is not
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specified (relative claims). So, perceptual states can be regarded as either relative or absolute only when regarded as involving cognitive claims. Arc the claims implicit in perceptual states relative or absolute? When I look at the table, which kind of implicit claim underlies the perceptual state of seeing its length? No doubt it is the absolute kind: the context, made up of the other objects surrounding the table, is specified, and the perception of the table's length is meaningfully determined. I see a certain determinate length of the table and not merely any length. The length of the perceived table may vary from, say, 1.8 to 2.2 meters, but not much more. This kind of indeterminacy leads to imprecise, but not meaningless, perception. In the same vein, I do not see a table of undetermined color; I see a green table. Again, the perceived color of the table may vary from light green to dark green, but usually not beyond this limited range of colors. The same is true for other perceptual qualities. They are meaningfully determined in a way that resembles an absolute, not a relative, claim. From a phenomenological point of view perception is not relative. Under normal circumstances perception is stable and meaningfully determined. Under abnormal circumstances perception is often indeterminate regarding not only precision but meaning as well. A lack of stability and determinacy is typical of ambiguous figures and of dreams. Common to these phenomena is an unspecified perceptual context. As mentioned above, “absolute" is not identical with “universal.” Therefore, the absolute nature of most perceptual states does not imply the exclusion of alternative perceptual perspectives. It implies only that in the given perspective the claim does not need further specification in order to be meaningfully determined. The fact that several people, or the same person on various occasions, may perceive the same object differently means that we have a variety of perceptual perspectives, not that perception is relative. A perceptual perspective may be unique to a certain individual, a group of individuals, or even to all mankind; but, unique is not the same as relative. Whereas something “unique" has no like or equal, something “relative" is a claim with an unspecified context and an indeterminate meaning. Perceptual knowledge is sometimes unique, but it is not usually relative. Those who speak about perceptual relativism often give "relative” a meaning similar to what I regard as "relational.” In this case, however, the traditional contentions concerning perceptual indeterminacy and incompatible diversity are not warranted. If the claim "perception is relative" merely implies that perception, like other forms of cognition, refers to a certain presupposed cognitive perspective, I would agree with it. 1 would use the term "relational" instead of "relative,” but this is only a terminological difference. However, I suspect the difference to be more than terminological. The assumed relative nature of perception in traditional models implies not only a reference to a certain cognitive perspective, but an incompatible diversity as well. I am opposed to this latter contention.
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Perceptual content, then, is relational and organized. Now I wish to discuss the problem of whether such perceptual content can function as the "given” for cognition. The given is both the starting point of cognitive processes and determines the adequacy of cognitive claims. To fulfil these functions, the given should have two features: (a) it should be pure, i.e., independent of the cognitive system, and (b) it should have some relevant cognitive content. The first feature assures that circularity is avoided: if the given depends upon the cognitive system, how can the given determine the system’s adequacy? The second feature is needed because only something with a meaningful, cognitive content can determine the adequacy of cognitive claims. A conflict exists between these features. Something having cognitive content cannot be pure, and something pure cannot have cognitive content. This is so since meaningful content does not float freely in the air; the content becomes meaningful with respect to a certain cognitive system when that system organizes the content to fit the system’s structure.42 The two conflicting features of the given stand for two possible concepts of the given: (a) a pure, meaningless, independent given, and (b) a meaningful, “contaminated,” dependent given. Each of these concepts presents its own difficulties. In the case of a pure, but contcntless (meaningless) given there is a logical difficulty: How can contentless material determine the adequacy of various cognitive contents? A pure given cannot overcome this logical gap, so in principle it cannot fulfiJ its cognitive function.43 In the case of a meaningful, but contaminated given the difficulty is that of circularity: How can we be certain of our cognitive claims if the initial cognitive state is not certain (since it has already been contaminated by subjective contributions)? rhe meaningful given can determine the adequacy of cognitive claims. There arc, however, doubts concerning how well it actually completes this task. I his difficulty may be conceived as a logical one only if cognitive claims arc thought to be certain and the given is also thought to be the basis for their certainty. When we are satisfied with less than certainty, we do not have to assume that the given is completely independent of the cognitive system. We may amve at very plausible claims by comparing different kinds of givens and other available information. With this multiple determination our claims may not be certain, but they surely can be highly probable. It is less important if the starting point is indubitable when cognition relies on more than one foundation. In this case each cognitive content, including its starting points, is subject to further research and modification. It would seem, then, that the meaningful given, that is, the given of a constructive nature, is not only the one actually found in perception and scientific knowledge, but also the only given which can determine the adequacy of cognitive claims. A central epistemological problem of perceptual dualism is the relation between perceptual and physical entities. Usually this relation is conceived as representational: internal perceptual signs represent external physical objects by resembling them, or by corresponding to them. In rejecting the existence of internal perceptual signs I do not also reject any
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kind of representation. Since in rny view the perceptual and physical descriptions arc two perspectives of the same world, we may say that the perceptual environment represents the physical world in some sense. for survival purposes it is valuable that some features or regularities of the physical world arc represented in perception. However, a perceptual stale docs not mask a single physical state standing behind it. Physical states arc related to, and expressed in, the perceptual environment and the perceptual system in many ways. Hence, it is preferable to speak about the perceptual aspects, not the perceptual representations, of the objects. Perceptual representation can be understood, as an emergent aspect of successful activity of the cognitive system.44 The perceptual environment is not a curtain hiding the physical world; it is, rather, a huge reservoir of the perccivcr’s tacit knowledge of that world. Perceptual relations and differences can be regarded as organized knowledge of the physical world expressed in a language understandable to the perceiver. A reflexive knowledge of that language is essential for understanding the physical world. This type of perceptual representation does not preclude other ways to directly encounter the physical world. Our bodies' physiological processes are directly influenced by states of the physical world, and perceptual states do not mediate this influence. Considering perception as a kind of cognition is a basic contention of my view. Perception is an important way of acquiring information, or belief-like states about our environment. I will now describe a few implications of this contention for both the lower forms of perception found in animals and for the higher forms of cognition found in conscious, intellectual thinking. The basic features of the human perceptual system should be applied to those of animals as well. In both cases the perceptual system is a cognitive system utilizing information about the environment. However, different perceptual systems may make use of various types of information. In the case of a primitive perceptual system capable of registering only a few types of relations, it is not relevant to speak about a perceptual knowledge. The more complex the relations a perceptual system is sensitive to, the more appropriate it is to speak about perceptual knowledge. The human perceptual system can handle more relations than an insect’s perceptual system; consequently, the human system is a higher-order cognitive system. Very primitive life forms cannot be described as having cognitive systems, but as having only a certain sensitivity to changes in their own subjective state. While they lack the intentional dimension, they probably do have the feeling dimension. Thinking can refer to more phenomena and relations than just those referred to by the perceptual system. Thus, thinking involves reflexive knowledge which does not exist (or exists in a primitive manner) a! the perceptual level. In this sense, thinking is a more suitable tool for the theoretical understanding of the world. It has been argued that once human beings become equipped with linguistic abilities there is a quantitative change in their perceptual content. This is true (so it has been claimed) regarding both the
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difference between humans and animals and that between human adults and human infants. I agree that language may influence the perceptual content, but I would not postulate a clear-cut dichotomy between the perception of those having linguistic abilities and those lacking them. As indicated in Chapter 1, infant perception is quite rich and includes some meaningful content similar to those found in adult perception. There arc also some similarities between human perception and animals perception. f Often perception is described as involving an application o concepts. This description can be misleading if concepts arc understoo to mean intellectual concepts. If. however, as Heil argues, by having a concept X, one can merely mean having the capacity to distinguis i s from non-Xs (under favorable conditions) then this desenp ioni is adequate. This capacity, thouch. does not require the ability o e i Xs. In this sense a perceptual concept is somewhat similar to background knowledge, or belief-like cognitive states. avig perceptual belief is like having an ability, whereas having an F1 % . belief involves the capacity to explicate and explain the belief, n beliefs are usually explicit and expressed by more comp ex yp concepts such as symbols (where a symbol is a complex concept.winch stands for more than one thing). Perceptual beliefs arc simp , implicit in the perceptual experience and arc expressed wi 10 . of linguistic symbols. In order to avoid implausibly’ascribing intenectu beliefs to flies and spiders, perceptual beliefs may be terme states." Sometimes there are conflicts between P^cPtua' states and intellectual beliefs. We perceive the sun to be small o have the intellectual belief that it is very’ big. A pcrccp ua ar.ac;tv an internal mediating entity, but a capacity. The employing or being shaped in light of a certain tendency, is no direct temporal process. Consequently, perceiving can be regar t:on contentful understanding; like other types of understanding, p P is influenced by the agent’s cognitive framework. 1 have distinguished a few components in ana yzing perceptual experiences: (a) physiological processes, ~>) ‘‘Vt* ’’ntai feeling, (c) perceptual content, and (d) perceptual form, nmi , states include at least the first two components. Developed pcrccptua states include all four components. These components arc simu ai ■ aspects of the same complex experience. Primitive creatures may n have the third and the fourth stages, but we should not desen e cm having non-epistemic (or pure) perception. Their experience is no perceptual since it is not intentional. There arc no distinct boun ancs between creatures with only feeling states and those with pnmi ivc perceptual states. The fuzzy boundaries, which arc typical of other mental states as well, do not pose any problem for my view, which assumes the prototypical nature of mental states. My explanation oi perception presents principles which are supposed to be applicable across the phylogenetic spectrum.46 This agrees with the stratification approach which assumes a certain continuity in the emergence of mental states.
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The dualistic approach to perception, like the dualistic approach to the mind-body problem, assumes the existence of an unbridgeable gap between humans and other life forms. The continuity suggested here explains the emergence of the most complex perceptual (and mental) systems, although it docs not assume all perceptual systems to be identical. In summary, I have argued that perceiving constitutes a 'direct encounter with meaningful content. There is no need to assume a meaningless sensory stage and an intellectual process connecting it to meaningful everyday perception. Perceiving is a type of direct cognition. The next chapter discusses a cognitive model which indeed permits a meaningful (nonpure) and direct perception. But first, the ontological status of the perceptual environment must be clarified.
(3.5) The Ontological Status of the Perceptual Environment
Naive realism assumes that perceptual qualities exist independently of the perceiver, whereas extreme subjectivism assumes they are properties of the perceiver. I indicated the flaws of both these views. A quantitative compromise between them is to divide the perceptual environment into two parts: one in which naive realism is correct and one in which the subjectivist view holds true. The distinction between primary and secondary qualities is just such a solution. Only the mental ideas of primary qualities have “resemblances” to the qualities of bodies, and "their patterns do really exist in the bodies themselves. The ideas of secondary qualities are merely signs of bodily dispositions. Although the distinction between primary and secondary qualities is absent in ancient philosophy, somewhat similar distinctions can be found. Aristotle made a distinction between special perceptual objects (eg., colors, sounds and smells) and common perceptual objects (e.g., motion, size and figure). He categorized perceptual objects in a way similar to the distinction between primary and secondary qualities. Contrary to the modern distinction, however, Aristotle’s special objects arc neither internal nor subjective mental signs. Moreover, since perceiving the special objects is a more natural function of the perceptual system than perceiving common objects, their perception is more likely to be true. Similarly while most modern perceptual theories conceive color as merely a mental subjective sign which does not exist in physical objects, many ancient theories of vision held color to be a real property of bodies.49 Distinguishing between primary and secondary' qualities is a problematic solution to the difficulties of the ontological status of the perceptual environment. Berkeley, for example, argues that considerations valid for perceiving secondary qualities can be applied to the perception of primary qualities as well. T hus, primary qualities arc no less subject to illusions and perceptual relativity than arc secondary qualities. On the other hand, Ixibniz argues that secondary qualities also
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exPre- the objects’ properties. This relation between secondary qualities and the objects properties, though, is not like a copy as in a picture, but like the projection which exists between a three-dimensional globe and a two-dimensional map. I believe that in an important sense all perceived qualities, rather than being properties of an independent physical world, are in some sense subject-dependent. In its progress, science is going further away from the perceptual content. The world described by physics is becoming less and less available to perceptual awareness. Physics does not actually attempt to copy perceptual qualities, it substitutes them with physical entities. The basis of theoretical physics cannot be derived from perceptual experience.5 The claim that perceptual qualities arc not copies of physical ones is supported by the fact that even the response of a nerve cell docs not copy the physical nature of the stimulus. It is simply sensitive to changes in the stimulus's intensity. The sensory receptive cells are “blind" to the quality of their stimulation. They are responsive only to changes in the quantity of that stimulation.51 In an unperceived forest there are no actual colors and sounds. This claim may sound odd because we imagine a forest with colors and sounds, but without human beings or any other pcrccivcr. It may be more helpful to imagine a forest as seen by a blind person and heard by a deaf one. Both lack the relevant perceptual capacities. The unperceived forest contains colors and sounds merely in a dispositional sense: if a perceivcr were present colors and sounds would be perceived. Analogously, an acid not in contact with a corrodible substance has only the dispositional property of corrosiveness. It cannot corrode anything since it has nothing to corrode. Something only becomcs^food when there are organisms with a digestive system disposed to cat it. Although perceptual qualities are properties of perceptual objects, they arc not necessarily properties of the underlying physical basis of the objects. 1 he properties of complex wholes arc not necessarily also properties of their parts, and vice versa. McGinn presents a similar characterization of the secondary qualities, but insists that there is a crucial ontological difference between secondary and primary qualities.53 In accordance with the Ixickcan tradition, he argues that secondary qualities stand for dispositions of objects to produce experiences, while primary qualities arc properties of an independent and objective world. We may say that secondary qualities are merely (arbitrary) signs of independent physical properties, while primary qualities (adequately) mirror these physical properties. Whereas primary qualities are constitutive of an external and objective world, secondary qualities are constitutive of merely the perceptual experience of this world. Hence, physical sciences speak of primary, but not of secondary, qualities in formulating their laws. Secondary qualities, McGinn argues, constitute a subjective grid contributed by the mind; this grid is necessary for any type of perception, but not for thought. Scientific thought is not a faint copy of secondary qualities, and in this sense there is a radical discontinuity between perception and thought; but
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thought involves the same primary qualities which are perceived in perception. Thought (at least adequate thought) is not contaminated by subjective features as perception is. Although particular scientists may distort the objective content of scientific theories, these theories airn at describing an independent world. 'The perceptual world, McGinn claims, includes both primary and secondary qualities, whereas the objective world includes only primary qualities. I believe that McGinn is right in insisting oni an important difference between primary and secondary qualities iregarding their relation with physical properties. Primary qualities arc closer to physical properties; they are part of both the perceptual environment and the physical world. Thus, primary qualities arc not constituted merely by their perceptual manifestations: a man bom blind cannot have the concept of red but can have the concept of squareness. Primary qualities exist both in the macroscopic and microscopic levels of describing the world. Unlike secondary' qualities, primary qualities are perceived by various senses and can be measured by physical instruments, fSuch diverse sources of information indicate that primary qualitiess are common to a few cognitive perspectives and in this sense they are more objective. Indeed, in daily life and in science reality is often distinguished from illusion on the basis that reality can be detected in various ways. In this connection Aristotle assumes that because perceiving common objects (which are close to the primary qualities) is a less natural activity of the perceptual system than perceiving special objects (which are close to the secondary' qualities), we need to perceive them with more than one sense in order to obtain reliable information about them.5’ This reasoning, though different from the modem. seems also to involve a certain notion of robustness. After admitting that primary qualities are closer to properties of the independent physical world than secondary qualities are, it is still to be determined if perceptual primary qualities are identical (as McGinn assumes) with such physical properties. Primary qualities are concerned with space and time. However, the concepts of "space’' and “time” in some theories in modern physics arc different from those presupposed in perception. This is true of both the microscopic and macroscopic realms. In the microscopic realm there are physical theories which assume that space has more than three dimensions (in addition to time), and the theory of relativity suggests a different notion of time in a system which operates at a very high speed. The latter theory' shows time and space themselves to be a kind of secondary properties. Even Euclidean space of classical physics differs from perceptual space. Eor example, perceptual space is not homogeneous and has the distinction, lacking in Euclidean space, between right and left. The primary quality of motion serves as another example of the difference between the perceptual and physical realms. An object, motionless from a perceptual point of view, is not without motion on its physical level of description. I he number of objects we perceive, as well as their perceptual size and shape, are described differently when reference is made to the physical entities
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underlying the perceptual environment. Similarly, physical solidity is not always identical with perceptual solidity. It seems that both the perceived secondary and primary qualities are in a certain sense agent-dependent; this dependency, however, is expressed on different levels of description. It has been claimed that while secondary qualities arc agent-dependent already in relation to the microscopic level of Newtonian physics, the dependency of perceptual primary qualities is revealed only by considering the structure of the quantum level.5' It is clear that perceptual primary qualities do not mirror the physical properties as they arc. We may say, however, that on a certain level of physical description, the physical world is constituted by the kind of properties typical of perceptual primary qualities. Thus, although in many physical types of description physical motion is different from perceptual motion, both physical and perceptual descriptions involve the property of motion. In its development physics replaced secondary qualities with primary qualities; when physics has replaced perceptual primary qualities it has done so by positing different types of primary qualities. This is another indication that primary qualities are closer to physical properties than secondary qualities are. McGinn’s view may give the impression that the only difficulty in arriving at adequate description of the independent objective world is that perceptual experience is infused with subjective elements (that is, secondary qualities) and once we get rid of these elements the road to the objective world is open. In my opinion this is too simplistic and mechanistic a view: there are various types and degrees of subjective contributions. The physical world is not simply the perceptual environment minus the secondary qualities; it is much more complex. Moreover, it is not only the perceptual description which involves a subjective contribution; the physical description (as any other description) involves it as well. Not only the perceiving mind, but also the thinking mind makes a subjective contribution to the content of experience. These contributions may be different in kind and degree, so one of them may be less distorting in nature than the other; but the cognitive mind is not a passive mirror of the objective world. No type of cognition is free of contamination by the subjective viewpoint. It is more useful to think of perceptual and physical descriptions as two different perspectives for describing the same world. 'I hese perspectives may have some common conceptual tools (such as the primary qualities), but they may also have different tools (such as different notions of space and time). In its early stages, the physical description was close to the perceptual one because it developed from the perceptual description. As physics develops, the gap between the two descriptions widens. The distinction between physical properties and secondary qualities was clear quite early in the development of modem physics. The difference between physical properties and primary qualities emerged only later. There are good reasons to believe that the future development of physics will only widen the gap. Both the perceptual primary qualities and the secondary qualities have a constructive nature
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and both belong to perceptual objects and not to independent, physical entities. The failure of a quantitative solution to the problem of the ontological role of the pcrcciver ought to lead us to a different approach. In one such approach I should like to suggest, a distinction is drawn between the perceptual environment and the physical world. Only the existence of the perceptual environment (but not of the physical world) presupposes the existence of a pcrcciver. My stand is not a middle position but a third, between naive realism and extreme subjectivism. In a nutshell, I argue that a distinction should be made between the viewpoint which is within the framework of the perceptual environment and the viewpoint which refers to the nature of that framework. In the former case realism is right: perceptual properties belong to objects existing in the perceptual environment. In the latter case, the relational nature of the perceptual environment should be stressed: the existence of the perceptual environment presupposes the existence of a perceiver. The difference between these two viewpoints can be exemplified by referring to the description of motion on earth. Is someone who is sitting still really motionless? The answer depends upon the chosen framework. If the framework is within the environment upon earth, then this person is motionless. If the framework is that of the solar system then the person is moving. In this same way colors and sounds exist within the perceptual framework, but not within the physical one. Despite the relational nature of perceptual qualities, they are perceived as properties of the objects in the environment and not as properties of the perceiver. This kind of objectification may vary with different senses and circumstances. As mentioned above, usually it is greater in the visual realm than in the tactile one. L nder abnormal conditions, such as illusions and intense emotional states, the perceptual objectification is less stable and we arc often aware of our role in determining the perceptual content. Under normal conditions such an awareness is usually absent, so we may consider ourselves as passive patients and not active agents. In one sense this impression is illusory since perceivcrs clearly have a constitutive role in perception. However, the impression of receptivity is not entirely illusory. For example, this impression is absent in thinking, emotions, or imagination. The impression of receptivity indicates that there is something involuntary in perception. We cannot perceive whatever we wish to. In perception, as in thinking or imagination, the nature of the mental system determines the intentional content. In perception, though, this is done in ways which the individual perceiver cannot choose since they are “wired” into the system in an involuntary manner. The involuntary manner of content delineation does not diminish the constitutive role of the perceiver in perception. As indicated earlier there are certain similarities between Kant’s approach and the relational approach suggested here. A comparison of the ontological status of the perceptual environment with that of Kant's empirical (phenomenal) w’orld also reveals a similarity. I will now
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summarize the main points of this similarity. Then 1 will clarify the ontological status of the perceptual environment. (A) The traditional problem which the approach attempts to overcome. Kant. Constructing a meaningful empirical work! by converting meaningless raw materials into meaningful objects. The relational approach: Constructing a meaningful perceptual environment by converting meaningless physical stimuli into meaningful perceptual objects and events. (B) The solution. Kant: Denying that the empirical subject directly encounters meaningless raw materials. The relational approach: Denying that the perceptual agent directly encounters meaningless raw materials. (C) The solution's grounding. Kant: A distinction between different levels of describing both the world (the empirical world, the transcendental objects, and the thing-in-itself) and the subject (empirical, transcendental, and the subjcct-in-itself). The relational approach: A distinction between different levels of describing both the world (physical and perceptual) and the agent (neural and perceptual systems). This perceptual level may be divided into an actual and a potential one. (D) The price of the solution. Kant: (a) The inability to know the thing-in-itself, and (b) the relational nature of the empirical world. The relational approach: (a) The inability to perceive the physical world-in-itself, and (b) The relational nature of the perceptual environment. A primary difference between the two approaches is that Kant applies his solution to the whole empirical world and to all types of cognition, whereas my approach refers only to one segment of them (perceptual environment and perceptual knowledge). Consequently, the problems facing Kant's approach are more severe. To explain the foundations of the empirical world, Kant has to invoke the problematic notion of the thing-in-itself (or subject-in-itself), which we can know nothing about. The thing-in-itself is not only' separate from and independent of the agent, it is also unknowable. I his idea can be understood only in the negative terms which arise from its comparison with the idea of things as they appear, namely, phenomena. All properties of known objects, such as existing in space, time, or casual relations, are not applicable to the thing-in-itself. The problematic Kantian notion of the thing-in-itself can be avoided in my approach if I suggest a reference-point fulfilling these two conditions: (a) it is independent of the perceptual system, and (b) its knowledge is not constituted by perceptual knowledge. The physical world seems to fulfd these conditions: it is clearly independent of the perceptual system and its knowledge goes beyond the perceptual given. Although some perceptual capacities are necessary in order to know the physical world (as for any other knowledge), these capacities arc not the cognitive tools used in describing and analyzing the physical world. In my approach the physical world may play the same role, but not exhibit the same difficulties, as does the thing-in-itself in Kant’s approach. Although the physical world cannot be known through perception, the
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existence of other cognitive capacities (such as thinking) allows the physical world to be known (unlike the thing-in-itsclf). Kant discusses the world and the subject on three levels: empirical, transcendental, and the thing-in-itsclf. In my discussion there arc two basic levels: perceptual and physical. Kant’s empirical level parallels my perceptual one, and his thing-in-itsclf level parallels my physical one. Kant’s transcendental level remains without a parallel. Docs my approach need a similar level? I believe so. Kant’s transcendental level fulfils the function of making a distinction between the actual realm of the activity (or cognition) of a particular empirical subject, and the possible realm in which all types of activity (or cognition) of every empirical subject could be described. The possible realm in Kant's view stems from the a priori structure of the subject. Pure a priori concepts, Kant argues, serve “as a priori conditions of a possible experience.”'’ I believe a similar actual-potential distinction is required in describing the perceptual environment. That environment includes any actual and potential properties of the surroundings perceived by the organism. Properties of the surroundings, unperceivable by the organism under any circumstances, do not belong to its perceptual environment. This description of the perceptual environment closely resembles the description of an ecological environment or biological niche: both have an organism-referential nature.5' Just as the empirical world in Kant's approach presupposes the existence of a subject, the perceptual environment presupposes the existence of a perccivcr. In this respect, the perceptual environment is relational. To paraphrase Kant’s claim: the a priori conditions of a possible (perceptual) experience in general are at the same time conditions of the possibility of objects of (perceptual) experience.'s Gibson, whose ecological approach is close to mine, asserts, along these same lines, that “the words animal and environment make an inseparable pair. Each tenn implies the other. No animal could exist without an environment surrounding it. 1-qually, although not so obvious, an environment implies an animal (or at least an organism) to be surrounded. This means that the surface of the earth, millions of years ago before life developed on it, was not an environment, properly speaking." speaking.' 59 When we speak of a perceptual environment, we presuppose there to beacontext in which there is a perccivcr. However organisms arc “not in the environment as coins are in a box.”6 The perccivcr and the perceptual environment exist as a pair just as a father and his son exist as a pair. The very same matt existed before his son was born, but then another aspect was added to him: being a father. In the same way the physical world existed before the emergence of perceptual systems, but then another level of description, the perceptual one, was added. Illis level can be characterized as the perceptual environment of a given perccivcr. Our main epistemological problem is then not so much that we cannot get in touch with the “real” world, but that we are too much in
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touch with it.62 Accordingly, the main epistemological task in connection with perception is the analysis of the meaningful, contaminated perceptual content, and not the addition of contentful materials to contcntless entities. . . In modem discussions “real” is sometimes identified with “physical" (or "material”), and “unreal" with “mental” (or “subjective ). I use these terms differently. “Real” and “unreal" are context-dependent attributes: something may be real in one context and unreal in another. Something is real in a certain context if it has relations to other things in that context. In the context of physical reality, moral values arc not re They arc real in the context of human behavior because they have a direct effect on the way people behave. In the context including on y perceptual properties (not their physical supporting basis), co ors an sounds arc real whereas wavelengths and photons are not. I here is a context where drcams are real: they are real experiences of the re,j ,' In dreams physical laws become unreal since they are constantly vio • Accordingly, “whatever is real in one such sense will be unrea in • Conversely every given content of experience is a reality o so The reality of something is determined by relations within the gi framework. Even’ reality has its own types and degrees of org , ’ its own rules and constraints. In the reality of imagination anddream our abiUty to make tilings real (in this context) is greater than our am j to do so in the perceptual reality. People can imagine alm