ASPECTS OF ARISTOTLE'S LOGIC OF MODALITIES

ASPECTS OF ARISTOTLE'S LOGIC OF MODALITIES

SYNTHESE HISTORICAL LIBRARY TEXTS AND STUDIES IN THE IllSTORY OF LOGIC AND PIffi.,OSOPHY Editors: N. KRETZMANN, Cornell University G. NUCHELMANS, University of Leyden Editorial Board: J. BERG,Munichlnstitute of Technology L. M. DE RDK. University of Leyden D. P. HENRY, University of Manchester J. HlNTIKKA, Florida State University. Tallahassee B. MATES, University of California. Berkeley J. E. MURDOCH, Harvard University G. PA1ZIG, University of Gottingen VOLUME 35

JEROEN VAN RIJEN Philosophy Department, Erasmus University, Rotterdam, The Netherlands ASPECTS OF ARISTOTLE'S LOGIC OF MODALITIES KLUWER ACADEMIC PUBLISHERS DORDRECHT / BOSTON / LONDON

Library of Congress Cataloging in Publication Data Rijen, Jeroen van, 1950- Aspects of Aristotle's logic of modalities / Jeroen van Rljen. p. cm. Based on the author's dissertatl0n--university of Leiden, 1986. Bibliography: p. Includes index. 1. Arlstotle--Contributions in logic of modalities. 2. Modality (Logic) I. Title. B491.L8R55 1989 166--dc19 88-31904 CIP ISBN-13: 978-94-010-7696-8 DOl: 10.1007/ 978-94-009-2651-6 e-isbn-13: 978-94-009-2651-6 Published by Kluwer Academic Publishers, P.O. Box 17, 3300 AA Dordrecht, The Netherlands. Kluwer Academic Publishers incorporates the publishing programmes of D. Reidel, Martinus Nijhoff, Dr W. Junk and MTP Press. Sold and distributed in the U.S.A. and Canada by Kluwer Academic Publishers, 101 Philip Drive, Norwell, MA 02061, U.S.A. In all other countries, sold and distributed by Kluwer Academic Publishers Group, P.O. Box 322,3300 AH Dordrecht, The Netherlands. AIl Rights Reserved 1989 by Kluwer Academic Publishers Softcover reprint of the hardcover 1st edition 1989 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.

CONTENTS PREFACE AND ACKNOWLEDGEMENTS ix CHAPTER ONE/ SUBJECT AND PROGRAMME 1. Introduction 2. Quandaries in recent Aristotle research 3. The programme of this study Notes to Chapter One 1 4 10 13 CHAPTER TWO/ THE GENERAL DOCTRINE I SOME THEOREMS AND RULES 1. Multifariousness and common core 2. A provisional assumption 3. Cornmon properties 4. Comparisons Notes to Chapter ~wo 15 16 16 25 28 CHAPTER THREE/ THE GENERAL DOCTRINE II ABSOLUTE AND QUALIFIED MODALITIES 1. Introduction 30 2. Qualified vs. absolute modalities 31 3. Qualified necessity, syllogisms and the proof per impossibile 36 4. Absolute impossibility and the commensurability of the diagonal 45 5. Real and assumed background knowledge 51 6. Relations between temporal and modal concepts 53 Notes to Chapter Three 56 CHAPTER FOUR/ MODALITY AND TIME (I) THE PRINCIPLE OF PLENITUDE 1. Introduction 2. The Principle of Plenitude and its role in Aristotle's modal thinking 3. The evidence Notes to Chapter Four 59 60 65 72

vi CONTENTS CHAPTER FIVE! MODALITY AND TIME (II) DE CAEW 1.12 AND THE NECESSITY OF WHAT IS ETERNAL 1. The problem 2. Williams and the supposed logical errors 3. Hintikka and the confusion in Aristotle's "Master Argument" 4. Judson and the "grossness of Aristotle's fallacy" 5. The metaphysics in De Caelo 1.12 as exposed by Waterlow 6. De Caelo 1.12 and the necessity of what is eternal 7. Some extrapolations and the role of hyle phtharte Notes to Chapter Five 73 74 79 81 82 87 95 101 CHAPTER SIX! MODALITY AND TIME (III) DE INTERPRETATIONE 9 1. Introduction 2. The traditional views 3. De Interpretatione 9 on the statistical reading 4. Deliberation and chance events in De Interpretatione 9 5. The interpretation Notes to Chapter Six 103 103 106 110 117 130 CHAPTER SEVEN! POSTERIOR ANALYTICS 1.4-6 THE DE OMNI-PER SE DISTINCTION 1. Introduction 2. Zabare11a on Aristotelian necessity 3. Inseparable accidents 4. A first look at Posterior Analytics 1.4-6 5. Some commentaries on Posterior Analytics 1.4 and 6 6. Real or conceptual modalities? 7. Aristotle, matter, and definition Notes to Chapter Seven 132 133 136 137 140 145 149 154 CHAPTER EIGHT! POSTERIOR ANALYTICS 1.4-6 NAMES AND NAMING 1. Abstraction in Metaphysics XIII.3 2. Abstraction and naming 3. The issue of names and naming 4. A new look at Posterior Analytics 1.4-6, part one 5. Some major differences 157 160 162 165 170

CONTENTS 6. A new look at Posterior Analytics 1.4-6, part two 172 7. Belonging kath' hauto and homogeneity 177 8. Homogeneity, the necessity of what is always and the concept of possibility 179 Notes to Chapter Eight 183 CHAPTER NINEj APODEICTIC SYLLOGISTIC 1. Introduction 185 2. External criticism 186 3. The nature of Aristotle's syllogistic theory 189 4. Apodeictic syllogistic 192 5. Incoherence 194 6. McCall's reconstruction 199 7. The four apodeictic categorical sentences and apodeictic ecthesis 200 8. The apodeictic conversion rules 205 9. The apodeictic Barbaras and domains of discourse 205 10. The status of ALuU 11. The soundness of the inference base 12. Conversion rules and shifts of type of predication 13. Conclusions Notes to Chapter Nine 209 210 212 214 216 BIBLIOGRAPHY 219 INDEX OF NAMES 229 INDEX OF SUBJECTS 233

~REFACE AND ACKNOWLEDGEMENTS This book is an elaboration of the study which I submitted as a dissertation at the University of Leiden in the autumn of 1986. It was conceived on the basis of the conviction that for all the work done on this subject, there is still not a satisfactory explanation of Aristotle's modal logic. To the present day all efforts to detect in Aristotle's works a coherent and consistent theory of modalities have utterly failed. Many studies of Aristotelian modalities have appeared which deal with various isolated aspects or with particular text fragments without any attempt to fit the findings into a more comprehensive framework which could be named 'Aristotle's modal theory'. Most of the studies with a wider scope have even ended up with the conclusion that there is no general Aristotelian theory of modalities. The few reconstructions which seek to show this theory to be coherent and consistent can, on the other hand, all be proved to be defective. These facts show that many of the ideas underlying Aristotle's handling of modalities are still obscure. Some of these ideas pertain to the meaning of the logical operators 'necessary' and 'possible'. To this day, not even the outlines of Aristotle's logic of these modal qualifiers are known. Nevertheless, knowledge of his modal logic seems clearly to be a necessary precondition for a complete understanding of the many doctrines and discussions of Aristotle in which modalities are involved. As a consequence it seems worth exploring Aristotle's modal logic not only for its own sake, but also for more general reasons. The present book is an exposition of several basic aspects of Aristotle's views on the logic of modalities. In the course of my exposition it will appear that the body of his theory as expounded in Chapters Two and Three of this study is simply and transparent. In fact, it is so simple that it will hardly be able to excite the formal logician. Yet, some aspects of Aristotle's extension of this basic theory, especially the semantical presuppositions of his logic of modally qualified categorical sentences as set out in Chapters Eight and Nine, may strike those who are working on theories of reference. As a consequence of this simplicity, readers who have no knowledge of modern formal logic should have no trouble with the main line of this study. Most of the argument will be completely accessible to them. Some basic knowledge of modern logic, however, will certainly facilitate the reading of Chapter Nine.

x PREFACE AND ACKNOWLEDGEMENTS The book opens with an exposition of the subject and programme of the study. Next, in Chapters Two and Three, Aristotle's general ideas about the logic of modalities are set out. Chapter Four introduces the main competing reconstruction of Aristotle's modal logic, i.e., Hintikka's interpretation in terms of the statistical model. In this model, what is always the case is necessary, and what is possible is at least once actualized. In the course of the next chapters, I develop my rejection of Hintikka's view while elaborating my own interpretation. In Chapter Five I show how the socalled proof of the necessity of what is always in De Caelo 1.12 can be incorporated in the general framework set out in Chapters Two and Three. Several other explanations of De Caelo 1.12, including that of Hintikka, are rejected. Chapter Six shows how an interpretation of De Interpretatione 9 can be provided on the basis of Aristotle's general theory of modalities. In Chapters Seven and Eight, the relation between omnitemporality or permanency and necessity in Posterior Analytics 1.4-6 is explored. It appears that there is no discrepancy between what Aristotle is saying here and the contents of De Caelo 1.12. Finally, in Chapter Nine, Aristotle's apodeictic syllogistic is examined. It is shown that its base consisting of the perfect apodeictic moods, the apodeictic conversion rules and apodeictic ecthesis is sound with respect to the interpretation Aristotle has in mind. Moreover, a striking variance between what is said about apodeictic syllogisms in Prior Analytics and in Posterior Analytics is dissolved. Hence, the outcome of this study is that Aristotle's modal logic exhibits a coherence and consistency which is much greater than it has usually been credited with. The debts I have incurred while I was writing this book are numerous. One of my principal debts is to Professor L.M. de Rijk of the University of Leiden, who has been a source of intellectual stimulation during the entire period of conceiving and preparing this work. Other persons have contributed to its completion as well. Professor G. Nuchelmans meticulously read an earlier version of this study and helped me with several valuable remarks. I have also profited from the criticism and advice of Professor H.M. Bracken, who draw my attention to various flaws in the penultimate version. Dr. J.A. van Eck criticized an earlier draft of Chapter Six. Professor S. Knuuttila commented on an older version of Chapter Seven, while Dr. E.C.W. Krabbe saved me from some infelicities in Chapter Nine. I owe thanks as well to Mr. J. Kearey, who corrected my English. Much of Chapter Seven ap-

PREFACE AND ACKNOWLEDGEMENTS xi peared in Van Rijen (1984), in Archiv fur Geschichte der Philosophie. I thank the editors of this Journal for permitting me to use this material again. Finally, I would like to express my gratitude to Ms. C. de Ruiter and Ms. M. Schoor1emmer, who produced the typescripts of several drafts of this text with great patience and care.