Science, Explanation, and Rationality: Aspects of the Philosophy of Carl G. Hempel JAMES H. FETZER, Editor OXFORD UNIVERSITY PRESS Science, Explanation, and Rationality Carl G. Hempel (1905–1997) Photograph by Jan Hempel (1985) Science, Explanation, and Rationality Aspects of the Philosophy of Carl G. Hempel Edited by JAMES H. FETZER 1 2000 3 Oxford New York Athens Auckland Bangkok Bogotá Buenos Aires Calcutta Cape Town Chennai Dar es Salaam Delhi Florence Hong Kong Istanbul Karachi Kuala Lumpur Madrid Melbourne Mexico City Mumbai Nairobi Paris São Paulo Shanghai Singapore Taipei Tokyo Toronto Warsaw and associated companies in Berlin Ibadan Copyright © 2000 by Oxford University Press Published by Oxford University Press, Inc. 198 Madsion Avenue, New York, New York 10016 Oxford is a registered trademark of Oxford University Press All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior permission of Oxford University Press. Library of Congress Cataloging-in-Publication Data Science, explanation, and rationality : aspects of the philosophy of Carl G. Hempel/edited by James H. Fetzer. p. cm. Includes bibliographical references and indexes. ISBN 0-19-512137-6 1. Hempel, Carl Gustav, 1905– I. Fetzer, James H., 1940– B945.H454 S35 2000 191—dc21 99–087642 987654321 Printed in the United States of America on acid-free paper TO PETER in memoriam This page intentionally left blank Editor’s Preface Although Carl G. Hempel was not unusually prolific by some standards (his bibliography reports 112 publications, including a few short monographs and an anthology of twelve articles), his influence was immense. At least twelve of his papers were instant classics, which not only exerted profound influence upon professional philosophers of science but spawned dozens and dozens of critical commentaries and learned replies. His influence upon teaching was similarly enormous. His Philosophy of Natural Science, for example, became the instant text of choice for introductory courses worldwide. Page for page, his achieve- ments were stunning. And as a human being, he was exemplary. As a philoso- pher, as a teacher, and as a human being, “Peter” was a paradigm. This volume complements The Philosophy of Carl G. Hempel, which reprints many of his most important articles on the central problems of philosophy of science, before and after his Aspects of Scientific Explanation. Authors of very high caliber, many of whom number among his former students, were invited to contribute, and their responses have been extremely gratifying. The pieces appearing here attest to the extraordinary stimulation and influence his work has exercised for more than half a century. I cannot imagine a more beneficial result than that this collection might contribute to preserving and perpetuating his con- tributions far into the twenty-first century. For a discipline that some of us are inclined to believe has lost its way, these studies should help in its rediscovery. All of the essays collected here were prepared especially for this book—with one exception: Wesley C. Salmon’s piece, “The Spirit of Logical Empiricism: Carl G. Hempel’s Role in Twentieth-Century Philosophy of Science,” which was pub- lished in Philosophy of Science 66 (1999), pp. 333–50. Nevertheless, that is as it should be. Many of Hempel’s most important publications appeared in Philosophy of Science. His influence upon the profession during the twentieth century was unparalleled. It is altogether fitting that this author, whose own contributions to many of the same subjects, including explanation, were exceeded only by those of Hempel, should be invited to have the last word—especially when, as in the case of the present volume, the last word reflects what may prove to be a new beginning. Duluth, Minnesota J. H. F. August 1999 This page intentionally left blank Contents Contributors xi Editor’s Introduction xv Prologue: An Intellectual Autobiography: Carl G. Hempel 3 Part I: Scientific Reasoning 1. Hempel and the Vienna Circle 39 MICHAEL FRIEDMAN 2. Hempel’s Logicist Philosophy of Mathematics: Background and Sequel 65 JAAKKO HINTIKKA Part II: Probability and Induction 3. Probable Inference versus Probable Conclusions 77 HENRY E. KYBURG, JR. 4. Hempel on the Problem of Induction 91 RISTO HILPINEN Part III: The Covering-Law Models 5. The Paradoxes of Hempelian Explanation 111 JAMES H. FETZER 6. Hempel’s Theory of Statistical Explanation 138 ILKKA NIINILUOTO x Contents Part IV: Theories and Predictions 17. The Symmetry Thesis 167 PETER ACHINSTEIN 18. Hempel and the Problem of Provisos 186 FREDERICK SUPPE Part V: Explanations of Behavior 19. Explanation in History 217 WILLIAM H. DRAY 10. Reasonable People 243 PHILIP KITCHER Part VI: Scientific Rationality 11. Analytic and Synthetic Understanding 267 PAUL W. HUMPHREYS 12. The Objectivity and the Rationality of Science 287 ROBERT NOZICK Epilogue: The Spirit of Logical Empiricism: Carl G. Hempel’s Role in Twentieth-Century Philosophy of Science 309 WESLEY C. SALMON A Bibliography of Carl G. Hempel 325 Index of Names 333 Index of Subjects 337 Contributors PETER ACHINSTEIN, Professor of Philosophy at Johns Hopkins University, received his B.A. in 1956 and his Ph.D. in 1961, both from Harvard University, where he was a student of Hempel during the 1953–54 academic year. The au- thor of Concepts of Science (1968), Law and Explanation (1970), The Nature of Explanation (1983), and Particles and Waves (1991, Lakatos Award), he is currently completing a new work entitled The Book of Evidence. WILLIAM H. DRAY, Emeritus Professor of Philosophy at the University of Ottowa, has held visiting appointments at Harvard, Stanford, Ohio State, and Duke Universities and at the Case Institute. His books include Laws and Explanation in History (1957), Philosophy of History (1964), Perspectives on History (1980), On History and Philosophers of History (1989), and History as Reenactment (1995). With W. J. van der Dussen, he recently edited a collection of philosophical manuscripts of R. G. Collingwood. JAMES H. FETZER, McKnight University Professor at the University of Min- nesota, Duluth, has published twenty books, including Scientific Knowledge (1981), AI: Its Scope and Limits (1990), Philosophy of Science (1993), and Phi- losophy and Cognitive Science (2nd ed., 1996). A recipient of the Medal of the University of Helsinki (1990), his undergraduate thesis for Carl G. Hempel won The Dickinson Prize (1962). He is the Editor of Minds and Machines and the Series Editor of Studies in Cognitive Systems. MICHAEL FRIEDMAN, Ruth N. Halls Professor of Arts and Humanities, Pro- fessor of Philosophy and of History and Philosophy of Science at Indiana Uni- versity, earned his Ph.D. at Princeton in 1973. Author of Foundations of Space- Time Theories (1983, Matchette Prize and Lakatos Award), Kant and the Exact Sciences (1992), and Reconsidering Logical Positivism (1999), he has served as President of the American Philosophical Assocation (Central Division) and of the Philosophy of Science Association. xi xii Contributors RISTO HILPINEN, Professor of Philosophy at the University of Miami, has also held visiting appointments at other universities in the United States, Australia, Austria, and Finland. An editor of Synthese, he has edited several books and has published more than one hundred papers in epistemology, philosophy of science, deontoic logic, and the philosophy of Charles S. Peirce. From 1983 to 1991, he served as Secretary for the Division of Logic, Methodology, and Philosophy of Science of the International Union of History and Philosophy of Science. JAAKKO HINTIKKA, Professor of Philosophy at Boston University, has authored over thirty books that have appeared in ten languages and has published more than three hundred scholarly papers. He is the principal architect of game-theo- retical semantics and of the interrogatory approach to inquiry and an architect of epistemic logic, distributive normal-forms, and possible-worlds semantics. His many distinctions include a John Locke Lectureship at Oxford (1964), Wihuri International Prize (1976), Guggenheim FeIlowship (1979–80), and Immanuel Kant Lectureship at Stanford (1985). PAUL W. HUMPHREYS, Professor of Philosophy at the University of Virginia, has written extensively on the nature of explanation and is the author of The Chances of Explanation (Princeton 1989). His other research interests include mathematical modeling, especially computational modeling, in the natural and social sciences; probability theory; emergent phenomena; and the nature of con- temporary empiricism. Currently completing a book on these topics, entitled Extending Ourselves, he is the Series Editor of Oxford Studies in the Philosophy of Science. PHILIP KITCHER, Professor of Philosophy at Columbia University, earned his Ph.D. from Princeton University. He is the author of several books and many articles on topics in the philosophy of science. His writings include The Nature of Mathematical Knowledge (1983) and The Advancement of Science (1993), and numerous essays on scientific explanation. With Wesley Salmon, he also co-edited Minnesota Studies in the Philosophy of Science, Vol. XIII (1989), on scientific explanation, a volume that was dedicated to Peter Hempel. HENRY E. KYBURG, JR. Burbank Professor of Philosophy and Computer Sci- ence at the University of Rochester, has authored or edited more