UNDERSTANDING PHILOSOPHY OF SCIENCE ‘This is the best introduction to philosophy of science I have read. I will certainly use it. The writing is wonderfully clear without being sim- plistic. It is not at all too difficult for second and third year students. Many of my philosophy of science students have no background in philosophy, and I’m sure they will find the book accessible, informa- tive, and a pleasure to read. I read this manuscript with my students in mind. This is the book we’ve been looking for.’ Peter Kosso, Northern Arizona University Few can imagine a world without telephones or televisions; many depend on computers and the Internet as part of daily life. Without scientific theory, these developments would not have been possible. In this exceptionally clear and engaging introduction to the philosophy of science, James Ladyman explores the philosophical questions that arise when we reflect on the nature of the scientific method and the knowledge it produces. He discusses whether fundamental philosophical questions about knowledge and reality might be answered by science, and considers in detail the debate between realists and antirealists about the extent of scientific knowledge. Along the way, central topics in the philosophy of science, such as the demarcation of science from non-science, induction, confirmation and falsification, the relationship between theory and observation, and relativ- ism, are all addressed. Important and complex current debates over under- determination, inference to the best explanation and the implications of radical theory change are clarified and clearly explained for those new to the subject. The style is refreshing and unassuming, bringing to life the essential ques- tions in the philosophy of science. Ideal for any student of philosophy or science, this book requires no previous knowledge of either discipline. It contains the following textbook features: • suggestions for further reading • cross-referencing with an extensive bibliography. James Ladyman is Lecturer in Philosophy at the University of Bristol, UK. UNDERSTANDING PHILOSOPHY OF SCIENCE James Ladyman London and New York First published 2002 by Routledge 11 New Fetter Lane, London EC4P 4EE Simultaneously published in the USA and Canada by Routledge 29 West 35th Street, New York, NY 10001 Routledge is an imprint of the Taylor & Francis Group This edition published in the Taylor & Francis e-Library, 2002. © 2002 James Ladyman All rights reserved. No part of this book may be reprinted or reproduced or utilised in any form or by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying and recording, or in any information storage or retrieval system, without permission in writing from the publishers. British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library Library of Congress Cataloging in Publication Data Ladyman, James, 1969– . Understanding philosophy of science/James Ladyman. p. cm. Includes bibliographical references and index. 1. Science – Philosophy. I. Title. Q175.L174 2001 501 – dc21 2001048105 ISBN 0–415–22156–0 (hbk) ISBN 0–415–22157–9 (pbk) ISBN 0-203-46368-4 Master e-book ISBN ISBN 0-203-77192-3 (Glassbook Format) For Audrey Ladyman Contents Preface xi Acknowledgements xiii INTRODUCTION 1 Philosophy of science as epistemology and metaphysics 5 PART I THE SCIENTIFIC METHOD 1 INDUCTION AND INDUCTIVISM 11 1.1 The sceptic’s challenge 11 1.2 The scientific revolution 14 1.3 The ‘new tool’ of induction 18 1.4 (Naïve) inductivism 27 Further reading 30 2 THE PROBLEM OF INDUCTION AND OTHER PROBLEMS WITH INDUCTIVISM 31 2.1 The problem of induction 32 2.2 Solutions and dissolutions of the problem of induction 40 2.3 Inductivism and the history of science 52 2.4 Theory and observation 56 2.5 Conclusions 58 Further reading 61 vii CONTENTS 3 FALSIFICATIONISM 62 3.1 Popper and the critique of Marxism and psychoanalysis 64 3.2 Popper’s solution to the problem of induction 69 3.3 The context of discovery and the context of justification 74 3.4 The Duhem problem 77 3.5 Problems with falsificationism 81 3.6 Conclusions 89 Further reading 91 4 REVOLUTIONS AND RATIONALITY 93 4.1 The received view of science 94 4.2 Kuhn’s revolutionary history of science 96 4.3 Paradigms and normal science 98 4.4 The Copernican revolution 105 4.5 Theory and observation 109 4.6 Incommensurability 115 4.7 Relativism and the role of reason in science 118 Further reading 123 PART II REALISM AND ANTIREALISM ABOUT SCIENCE 5 SCIENTIFIC REALISM 129 5.1 Appearance and reality 131 5.2 The metaphysics of the external world 138 5.3 Semantics 146 5.4 Standard scientific realism 158 5.5 Antirealism 159 Further reading 160 6 UNDERDETERMINATION 162 6.1 Underdetermination 162 6.2 Constructive empiricism 185 Further reading 194 viii CONTENTS 7 EXPLANATION AND INFERENCE 196 7.1 Explanation 198 7.2 Inference to the best explanation 209 7.3 Common sense, realism and constructive empiricism 225 Further reading 228 8 REALISM ABOUT WHAT? 230 8.1 Theory change 230 8.2 Multiple models 252 8.3 Idealisation 257 8.4 Structural realism 260 Further reading 262 Glossary 264 Bibliography 270 Index 276 ix Preface This book is intended to provide an introduction to the philosophy of science. In particular, it is aimed at science students taking a phil- osophy of science course but no other philosophy classes, as well as at those students who are studying philosophy of science as part of a philosophy degree. Hence, I have assumed no prior knowledge of philosophy, and I have not relied upon detailed knowledge of science either. I have also avoided using any mathematics. This means that some issues are not discussed despite their interest. For example, the implications of quantum mechanics for philosophy of science, and the mathematical theory of probability and its use in modelling scien- tific reasoning are not dealt with here. Nonetheless, an introductory text need not be superficial and I have tried to offer an analysis of various issues, such as induction, underdetermination and scientific realism from which even graduate students and professional philo- sophers may benefit. My aim throughout has been to make the reader aware of questions about which they may never have thought, and then to lead them through a philosophical investigation of them in order that they appreciate the strength of arguments on all sides, rather than to offer my own views. Hence, there are few answers to be found in what follows and if my readers are left puzzled where previously they were comfortable then I will be satisfied. I hope this book will also interest scientists and general readers who are curious about the philosophy of science. I have tried to keep the exposition clear and accessible throughout, and also to illustrate important lines of argument with everyday and scientific examples. However, the reader will find that the discussion in Chapter 5 is xi PREFACE largely about the historical and philosophical background to the con- temporary debate about scientific realism. Those who do not see its relevance immediately are urged to persevere, since the issues dis- cussed are of fundamental importance. Finally, I must confess in advance to historians that I have subordinated historiography to my pedagogical aims by sometimes presenting a narrative that only just begins to address the complexities and ambiguities of the historical development of philosophy and science. For the benefit of the reader, the first instances of each term expanded in the Glossary are set in bold. xii Acknowledgements I am very grateful to all those who have taught me about philosophy of science, but special thanks are due to Richard Francks, Steven French, David Papineau, Anthony Sudbery and Bas van Fraassen. Thanks to all my students, especially Carlton Gibson and Nick Talbot who gave me feedback on portions of this book at early stages. Katherine Hawley kindly allowed me to see her lecture notes on Kuhn, which were very helpful. Dawn Collins, Andrew Pyle, Paul Tappenden and an anonymous referee read the whole manuscript and gave me extensive comments for which I am extremely grateful. Thanks also to Leah Henderson who gave me useful advice on the later chapters, and Jimmy Doyle who eventually managed to read the preface and the acknowledgements. I would like to thank all my col- leagues in the Department of Philosophy at the University of Bristol for affording me study leave with which to write this book, and also the Arts and Humanities Research Board for a research leave grant. I am very grateful to Tony Bruce, philosophy editor at Routledge, who encouraged me to undertake this project, and to Siobhan Pattinson who guided it through the publication process. Finally, thanks to Audrey and Angela Ladyman for their love and support. Chapter 8 includes material reprinted from Studies in History and Philosophy of Modern Physics, vol. 28(3), French, S. and Ladyman, J., ‘Superconductivity and structures: revisiting the London account’, pp. 363–393; copyright (1997), with permission from Elsevier Science. Also, Studies in History and Philosophy of Science, vol. 29(3), Ladyman, J., ‘What is structural realism?’, pp. 409–424; copyright (1998), with permission from Elsevier Science. James Ladyman xiii Introduction In many ways, our age is no different from any other: most people work hard merely to survive, while a few live in the lap of luxury; many perish in wars and conflicts, the causes of which they have no control over; the cycle of birth, reproduction and death is funda- mentally the same for us as it was for our distant ancestors. Yet certain features of the contemporary world are quite new: for example, I can pick up the phone and speak to a relative on the other side of the globe, and I can see that it is indeed a globe that I inhabit by looking at a photograph taken from space; many people’s every- day lives are enhanced by, and unimaginable without, computers, televisions and music systems; medicine can treat forms of illness and injury that would have brought certain death for earlier generations.