PDF hosted at the Radboud Repository of the Radboud University Nijmegen The following full text is a publisher's version. For additional information about this publication click this link. http://hdl.handle.net/2066/145815 Please be advised that this information was generated on 2021-10-09 and may be subject to change. Real knowledge The problem of content in neural epistemics een wetenschappelijke proeve op het gebied van de Wijsbegeerte Proefschrift ter verkrijging van de graad van doctor aan de Katholieke Universiteit Nijmegen, volgens besluit van het College van Decanen in het openbaar te verdedigen op woensdag 14 september 1994, des namiddags te 1.30 uur precies, door Johannes Jacobus Martinus Sleutels geboren op 20 januari 1960 te Meijel promotor: prof.dr. A.A. Derksen ISBN 90-9007373-6 © 1994 by JJ.M. Sleutels Kronenburgersingel 265A, 6511 AS Nijmegen All rights reserved. Except for the quotation of short passages for the purposes of criticism and review, no part of the material protected by this copyright notice may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, recording or otherwise, without written permission of the copyright owner. Contents Preface 5 Chapter 1 Beyond the naturalistic fallacy 7 1. The unreality of knowledge 7 2. Masters of the universe 9 3. Neural epistemics and mental content 12 Chapter 2 Philosophy of mind. An overview 14 1. Cognition and psychology 15 2. The functionalist framework 18 3. The computational paradigm 21 4. Troubles with functionalism 26 5. The modularity of mind 33 6. Metaphysics of mind. A conceptual universe 39 Chapter 3 Eliminative materialism and folk psychology 45 1. Eliminative materialism 46 2. Conceptual or metaphysical arguments 52 3. Methodological arguments 62 4. Empirical arguments 68 5. Folk psychology explained 74 Chapter 4 Neural epistemics 79 2. Elements of connectionist architecture 81 2. Λ conceptual universe for connectionist theory 92 3. Neural epistemics. The cognitive allure of connectionism 102 4. Connectionism and mental content 113 4 Contents Chapter 5 Qualia and epistemic content 122 1. Qualia disqualified? 123 2. Weak qualia examined 131 3. Color qualia and the labeling fallacy 137 4. Strong plasticity of perception 142 5. Theory and observation 149 Chapter 6 Computationalism and narrow content 157 1. Punch cards and mental content 158 2. Миг reasons for internalism 171 3. Л Cartesian heritage 195 Chapter 7 Externalism and mental representation 201 1. Л general argument for externalism 202 2. Causal theories of representation 208 3. 77œ taming of the shrew 214 4. Second thoughts about externalism? 231 Chapter 8 Real knowledge in perspective 238 1. A short history of knowledge 239 2. Transcendental philosophy reconsidered 251 3. 77гг bone of content 259 4. BacJt to the future 266 Notes 271 Bibliography 289 Index 301 Summary in Dutch 315 Curriculum vitae 319 Preface Research for this study was begun in 1987, when I started out as a postgrad­ uate student of Ton Derksen at Nijmegen University, Department of Philoso­ phy. Work on it was continued as I transferred to the Department of Philos­ ophy at Leiden University in 1989, where I have since then been teaching metaphysics and theory of knowledge. Support from these institutions is gratefully acknowledged. Some of the material used in this study draws on previously published papers of mine. Earlier versions of chapters 3 and 5 were published in Dutch as Sleutels 1988 and 1993, respectively. These papers were rewritten for the present study, including new material and adding new parts. Some of the ideas developed in chapter 4 draw on a joint paper with Bart Geurts, then of the IBM Research Centre at Stuttgart, Germany, which was published as Sleutels and Geurts 1989. Parts of chapter 2 were originally prepared for the Handbuch Sprachphilosophie, eds. M. Dascal et al. (Berlin, De Gruyter), which is still forthcoming. Many teachers, colleagues, students and friends have helped to make this a different book from what it was when I first thought of it. I thank them for their inspiration and criticism as well as for manifold distractions. Chapter one Beyond the naturalistic fallacy 1. The unreality of knowledge This book springs from a single worry: that our knowledge of the world may not be real, in the sense that it may not be part of natural reality. Philosophers inform us that knowledge is logically prior to the world grasped by it, and that, therefore, it is not possible to study knowledge from a natural point of view. I want to explore this impossibility. I believe that knowledge is real, and that it is imperative to study it from that point of view. By the same token, the subjects of knowledge are part of natural reality, not something alien and sub­ lime. We human beings use our brains for thinking. If we want to study real knowledge, we must study brains. A landmark in contemporary discussions of knowledge, and an important source of the 'anti-realism' mooted here, is Wilfrid Sellers' criticism of the Myth of the Given (Sellare 1963). Seilars energetically opposed the idea that there is a privileged stratum of fact, facts that are taken as 'given', on which our empirical knowledge of the world is founded, and to which all meaning and truth can be reduced. Such 'givens', whether they are thought of as sense data or material objects, first principles, universals or propositions, are often supposed to act as the 'unmoved movers' of empirical knowledge. According to Seilars, all attempts to reduce knowledge to a privileged stratum of natural fact are doomed to fail. To make knowledge real in this sense is to commit a species of naturalistic fallacy: "the idea that epistemic facts can be analysed without remainder—even 'in principle'—into non-epistemic facts, whether phenomenal or behavioural, public or private, with no matter how lavish a sprinkling of subjunctives and hypotheticals is (...) a radical mistake—a mistake of a piece with the so-called 'naturalistic fallacy' in ethics" (Seilars 1963, 131). The backbone of Sellars' argument is his claim that knowledge is radically linguistic, while the alleged 'givens' are supposed to be not. According to 8 Chapter one Sellare, knowledge is not a matter of being in a certain empirical state, such as being affected by an object in certain ways, or being in a certain brain state. Rather, it is being in a logical state, a matter of relating to one's linguistic peers, of logically justifying one's assertions in the face of the language community. Sellare sharply distinguishes these two aspects of knowledge attribution: "in characterizing an episode or state as that of knowing, we are not giving an empirical description of that episode or state; we are placing it in the logical space of reasons, of justifying and being able to justify what one says" (op. cit., 169). Succinctly put, if I believe that apples are red, this fact cannot be analyzed into intrinsic facts about apples, nor into sensory impressions, behavioral disposi­ tions, or intrinsic features of my brain. My belief counts as knowledge just be­ cause my linguistic peers are typically prepared to accept my claim that apples are red. Knowledge is located in the 'logical space' of language; any attempt to analyze it as a natural process falls prey to the naturalistic fallacy. Consequences of the linguistic turn Sellare' criticism of the Myth of the Given exemplifies the linguistic rum in modern philosophy, other exponents of which are W.V. Quine (1953; 1960) and Ludwig Wittgenstein (1953). More recently, the linguistic rum was force­ fully epitomized by Richard Rorty in his influential book, Philosophy and the mirror of nature (1979). Rorty drives home the point that knowledge is not "a transaction between 'the knowing subject' and 'reality'" (Rorty 1979, 9). It is not something real, but something located in the self-contained sphere of dis­ course. According to what may be called the 'linguistic consensus' in contem­ porary philosophy, all efforts "to break out of discourse to an arche beyond discourse" are fruitless (Sellare 1963, 196; cf. Pols 1992, eh. 3). The linguistic tum holds some remarkable consequences for our conception of man, world, and knowledge. First, it invites us to sublimate the subject of knowledge as being no longer the empirical human self, but an abstract node in the web of discourse. The human self tends to become a mere "contributor" to the "ongoing conversation of mankind" (Rorty 1979), or a "center of narra­ tive gravity" (Dennett 1992). The self is thereby exiled from the world known by it. It is a serious problem in the philosophy of mind how to account for this unworldly nature of the subject. Secondly, the linguistic turn fosters a tendency to evaporate reality as an Beyond the naturalistic fallacy 9 independent constraint on knowledge. In the final analysis, the world's contri­ bution to knowledge is reduced to a series of ineffable surface irritations. The world can no longer be claimed to determine either the meaning, truth or va­ lidity of our empirical statements. This poses a severe threat to empiricism. In Rorty's well-known phrase, the world now seems to be well lost (Rorty 1972). Finally, the linguistic turn suggests that knowledge as such is not real. Knowledge becomes a thing alien and sublime, something not-of-this-world, as opposed to the world grasped by it. This is a serious problem for any aspir­ ing cognitive science. The professed aim of cognitive science is to study knowl­ edge as an empirical phenomenon. But if Sellare' criticism of the Myth of the Given is correct, no empirical account of knowledge can succeed, because knowledge is not an empirical reality.