INCOMMENSURABILITY AND RELATED MATTERS BOSTON STUDIES IN THE PHILOSOPHY OF SCIENCE Editors ROBERT S. COHEN, Boston University JURGEN RENN, Max-Planck-Institute for the History of Science KOSTAS GAVROGLU, University ofA thens Editorial Advisory Board THOMAS F. GLICK, Boston University ADOLF GRUNBAUM, University of Pittsburgh SYLVAN S. SCHWEBER, Brandeis University JOHN J. STACHEL, Boston University MARX W. WARTOFSKYt, (Editor 1960-1997) VOLUME 216 INCOMMENSURABILITY AND RELATED MATTERS Edited by PAUL HOYNINGEN-HUENE University of Hannover, Germany and HOWARD SANKEY University of Melbourne, Australia Springer-Science+Business Media, B.V. A c.I.P. Catalogue record for this book is available from the Library of Congress. ISBN 978-90-481-5709-9 ISBN 978-94-015-9680-0 (eBook) DOI 10.1007/978-94-015-9680-0 Printed on acid-free paper All Rights Reserved © 2001 Springer Science+Business Media Dordrecht Originally published by Kluwer Academic Publishers in 2001. Softcover reprint of the hardcover 1st edition 2001 No part of the material protected by this copyright notice may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording or by any information storage and retrieval system, without written permission from the copyright owner. TABLE OF CONTENTS HOWARD SANKEY / Introduction vii PAUL HOYNINGEN-HUENE INCOMMENSURABILITY, MEANING AND REFERENCE RICHARD N.BOYD Reference, (In)commensurability and Meanings: Some (Perhaps) Unanticipated Complexities MARTIN CARRIER Changing Laws and Shifting Concepts: 65 On the Nature and Impact ofIncommensurability FRED KROON/ Ramsification, Reference Fixing and 91 ROBERT NOLA Incommensurability REALISM AND INCOMMENSURABILITY HAROLD I. BROWN Incommensurability and Reality 123 MICHAEL DEVITT Incommensurability and the Priority of 143 Metaphysics INCOMMENSURABILITY, RATIONALITY AND RELATIVISM GERALD DOPPEL T Incommensurability and the Normative 159 Foundations of Scientific Knowledge DUDLEY SHAPERE Reasons, Radical Change and 181 Incommensurability in Science INCOMMENSURABILITY, MUL TICUL TURALISM AND SCIENCE EDUCATION HARVEY SIEGEL Incommensurability, Rationality and Relativism: 207 In Science, Culture and Science Education HUGH LACEY Incommensurability and 'Multicultural Science' 225 vi T ABLE OF CONTENTS INCOMMENSURABILITY, COGNITION AND CONCEPTUAL CHANGE PETER BARKER Incommensurability and Conceptual Change 241 During the Copernican Revolution NANCY J. NERSESSIAN Concept Formation and Commensurability 275 303 INCOMMENSURABILITY BIBLIOGRAPHY NOTES ON CONTRIBUTORS 317 INDEX OF NAMES 321 HOWARD SANKEY / PAUL HOYNINGEN-HUENE INTRODUCTION 1. THE INCOMMENSURABILITY THESIS The aim of this book is to assess the merits and current fortunes of one of the most controversial theses to emerge in the philosophy of science during the latter half of the twentieth century. This is the thesis of the incommensurability of scientific theories. The controversy about incommensurability dates to the year 1962, the year in which the thesis of incommensurability was first explicitly proposed by its two chief advocates, Paul Feyerabend and Thomas Kuhn. It is convenient to treat the year 1962 as the year in which the incommensurability thesis first emerged because that is when the thesis was first asserted in print by F eyerabend and Kuhn. F eyerabend originally claimed that some successive theories may be incommensurable in his paper "Explanation, Reduction and Empiricism" (1962).1 The claim was made in the course of his critique of the reductionist account of the relations between scientific theories proposed by logical empiricism. Kuhn ascribed a central role to incommensurability in his theory of the development of science as a sequence of revolutionary transitions between scientific paradigms, which he presented in his classic work The Structure ofS Cientific Revolutions (1962).2 It is, however, something of an oversimplification to take 1962 as the year in which the incommensurability thesis first emerged. For, in proposing the idea ofi nc ommen sur ability, Kuhn and Feyerabend were drawing on earlier developments in the philosophy and history of science, as well as in philosophy at large. In many respects, the incommensurability thesis is a product of the philosophical climate of the late 1950's and early 1960's. This was a time that saw the rise of the professional discipline ofthe history of science, the influence of Gestalt psychology on the philosophy of perception, the decline of the logical positivism of the Vienna Circle, the widespread influence of the later Wittgenstein and Quine'S attack on the analytic/synthetic distinction. Apart from being a product of its time, the incommensurability thesis is also one of the characteristic claims of a new movement in the philosophy of science that began to emerge in the late 1950's and early 1960's. Together with the thesis of the theory dependence of observation, the rejection of a fixed scientific method, and insistence on the importance of the history of science to the philosophy of science, the incommensur ability thesis is one of the leading claims of what came to be known as the post positivist or historical philosophy ofs cience. In addition to Kuhn and Feyerabend, other initial participants in this movement also included such figures as Norwood Russell Hanson, Michael Polanyi and Stephen Toulmin.3 vii P. Hoyningen-Huene and H. Sankey (eds.). Incommensurability and Related Matters, vii~xxxiv. © 2001 Kluwer Academic Publishers. viii HOWARD SANKEY / PAUL HOYNINGEN-HUENE 2. WHAT IS INCOMMENSURABILITY? Before turning to the thesis of incommensurability, a word of caution is in order with regard to the concept of incommensurability itself. Productive discussion of the incommensurability thesis may at times be impeded by lack of consistent use or clear meaning of the term' incommensurability' . The term has a standard use in mathematics, where it implies the absence of a common unit of measurement. To say that two magnitudes are incommensurable is to say that there is no common unit of measure ment, whole units of which may be used to measure both magnitudes. But application ofthe mathematical concept to the case of alternative scientific theories is an extension of the concept that leaves considerable scope for alternative interpretations. Discussion of the incommensurability of scientific theories rarely proceeds in accordance with the mathematical concept of incommensurability. Instead, discussion of incommensurability tends to be framed in terms of a range of concepts and con siderations of a broadly semantic and epistemological nature. The discussion is fre quently couched, for example, in terms of such factors as the incomparability of the content of scientific theories, variation in the meaning of scientific terms, translation failure between the vocabulary of theories, or absence of common standards of theory appraisal. This raises the question of the relationship between the concept of incommensur ability in the strict sense of lack of a common measure, and the various other claims which have framed the discussion oft he incommensurability thesis. Is the incommensur ability of scientific theories some single, unified relation between theories, of which the various associated factors constitute mere aspects or component parts? Or is it instead the case that there are a number of different things, such as the incomparability of the content of theories, or lack of shared evaluative standards, which are each a source of incommensurability in their own right? To answer this question one way or the other is already to take a side in the dispute. The question of how to apply the concept of incommensurability in the present context is itself one of the questions at stake. Some parties to the dispute take incommensur ability to be a relation that may obtain in its own right between theories, of which such things as meaning variance and lack of shared evaluative standards are mere aspects or constitutive parts. In contrast, other parties to the dispute treat the claim of incommen surability as consisting entirely in one or another of the various claims associated with talk of incommensurability, such as the claim that the content of alternative theories is unable to be compared due to meaning variance ofthe terms employed by the theories. Given such potential variation in use, it is important to bear in mind that not all parties to the dispute may understand the concept of incommensurability in the same way.4 3. ARE THERE DIFFERENT FORMS OF INCOMMENSURABILITY? Let us now tum to the thesis of incommensurability. If one takes an overview of the critical literature concerned with the incommensurability thesis, it can hardly escape notice that this literature contains a variety of separate discussions that are conducted in quite different terms. Some authors write about the topic of meaning variance and INTRODUCTION ix content comparison. Some write about conceptual change and the intelligibility of alternative conceptual schemes. Others write about scientific realism and the continuity of reference of theoretical terms. And still others are concerned with the rationality of scientific theory choice, and the availability of objective standards oftheory evaluation. The need to address a variety of issues under the heading of incommensurability owes much to the original discussion by Kuhn and Feyerabend. In his original discussion of the topic in "Explanation, Reduction and Empiricism", Feyerabend took incommensurability to consist in absence of logical relations due to semantic variance of the terms used by theories, resulting in the inability to directly compare the content of theories (198Id, pp. 62-69, 92-93). By contrast, in The Structure of Scientific Revolutions, Kuhn treated incommensurability as a multi-dimensional relationship between paradigms, which involves methodological, semantic and perceptual com ponents (Kuhn, 1970a, pp. 148-150). According to Kuhn, paradigms employ diverse standards of theory appraisal, and address different sets of scientific problems. The vocabulary employed by scientists changes meaning in the transition between paradigms. Scientists in rival paradigms perceive the world differently. Perhaps they even inhabit different worlds. With so many themes already present in Kuhn's and Feyerabend's original discussion, it is no wonder that a host of issues emerged when other philosophers turned to the topic. To impose order on the discussion, we will introduce a distinction between two versions ofthe incommensurability thesis. The first version, which we will call the semantic incommensurability thesis, is the thesis that alternative scientific theories may be incommensurable due to semantic variance of the terms employed by theories. The second version, which we will call the methodological incommensurability thesis, is the thesis that alternative scientific theories may be incommensurable due to absence of common standards of theory appraisal. We will now sketch the main developments that have taken place in connection with each of these two versions of the incommensur ability thesis. 4. SEMANTIC INCOMMENSURABILITY The thesis of semantic incommensurability derives from the claim of Kuhn and Feyerabend that the meaning of the terms employed by theories varies with theoretical context. Both authors reject the empiricist idea of an independently meaningful, theory neutral observation language. Instead, they claim that the meaning of the terms employed by scientific theories depends on the theoretical context in which the vocabulary is employed. Given the contextual nature of meaning, the meaning of scientific terms is subject to variation with the theory in which they occur.5 The thesis of meaning variance gives rise to the thesis of semantic incommensur ability in the following way. Because the meaning of the terms employed by scientific theories varies with theoretical context, the vocabulary of such theories may fail to share common meaning. But if theories are unable to be expressed by means of a common vocabulary, the content ofs uch theories cannot be directly compared. For in the absence of a shared, semantically neutral vocabulary, it is impossible for statements about the world asserted by one theory to either assert or deny the same thing as any statement made by the other theory.6 Theories which are unable in this way either to agree or