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REFORGING THE GREAT CHAIN OF BEING HISTORICAL LIBRARY

TEXTS AND STUDIES IN THE HISTOR Y OF

LOGIC AND

Editors:

N. KRETZMANN, Cornell University

G. NUCHELMANS, University of Leyden

L. M. DE RIIK, University of Leyden

Editorial Board:

J. BERG, Munich Institute of Technology

F. DEL PUNT A, Linacre College, Oxford

D. P. HENR Y, University of Manchester

J. HINTIKKA

B. MATES, University of California, Berkeley

J. E. MURDOCH,

G. PAT Z IG, University of Gottingen

VOLUME 20 REFORGING THE GREAT CHAIN OF BEING

Studies of the History ofModal Theories

Edited by

SIMO KNUUTTILA , Dept. of Philosophy, Helsinki, Finland

SPRINGER-SCIENCE+BUSINESS MEDIA, B.V. Library of Congress Cataloging in Publication Data

Main entry under title:

Reforging the great chain of being.

(Synthese historicallibrary ; v. 20) lncludes bibliographies. 1. Modality ()-Addresses, essays, lectures. 2. Modality (Theory of knowledge)-Addresses, essays, lectures. 1. Knuuttila, Simo,1946- II. Series. BC199.M6R36 160 80-19869 ISBN 978-90-481-8360-9 ISBN 978-94-015-7662-8 (eBook) DOI 10.1007/978-94-015-7662-8

Ali Rights Reserved Copyright © 1981 by Springer Science+Business Media Dordrecht Originally published by D. Reidel Publishing Company, Dordrecht, Holland in 1981 Softcover reprint of the hardcover 1st edition 1981

and copyright holders as specified on the appropriate pages within. 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, inc1uding photocopying, recording or by any informational storage and retrieval system, without written permission from the copyright owner T ABLE OF CONTENTS

INTRODUCTION vii

JAAKKO HINTIKKA I Gaps in the Great Chain of Being: An Exer• cise in the Methodology of the History of Ideas MICHAEL DAVID ROHR I Empty Forms in 19 JAAKKO HINTIKKA I on the Realization of Possibilities in Time 57 R. M. DANCY I Aristotle and the Priority of Actuality 73 EILEEN F. SERENE I Anselm's Modal Conceptions 117 SIMO KNUUTTILA I Time and Modality in 163 JAAKKO HINTIKKA I Leibniz on Plenitude, Relations, and the 'Reign of Law' 259 JAAKKO HINTIKKA and HEIKKI KANNISTO I Kant on 'The Great Chain of Being' or the Eventual Realization of All Possi- bilities: A Comparative Study 287

INDEX OF NAMES 309

INDEX OF SUBJECTS 315 INTRODUCTION

A sports reporter might say that in a competition all the participants realize their potentialities or possibilities. When an athlete performs far below his usual standard, it can be said that it was possible for him to do better. But the idea of fair play requires that this use of 'possible' refers to another com• petition. It is presumed that the best athlete wins and that no real possibility of doing better is left unrealized in a competition. Here we have a use of , a language game, in which modal notions are used so as to imply that if something is possible, it is realized. This idea does not belong to the general of current ordinary usage. It is, nevertheless, not difficult to fmd other similar examples outside of the language of sports. It may be that such a use of modal notions is sometimes calculated to express that in the context in question there are no real alternative courses of events in contradistinction to other cases in which some possible alternatives remain unrealized. Even though modal notions are currently interpreted without the presup• position that each genuine possibility should be realized at some moment of the actual history, there are contemporary philosophical models of modalities which incorporate this . In his book Untersuchungen tiber den Modalkalkiil (Anton Hain, Meisenheim am Glan 1952, pp. 16-36), Oscar Becker presents a statistical interpretation of modal calculi. The basic defmi• tions are as follows:

(1) op = (x)P(x) == ~(Ex)~P(x) (2) ~Op =~(Ex)P(x) == (x)~P(x) (3) Op = (Ex)P(x) == ~(x)~P(x) (4) ~o p = ~(x)P(x) == (Ex)~P(x)

(0 stands for necessity, 0 for possibility). In this interpretation it is pre• supposed that there is a variable element in modal . 'Necessity' and 'possibility' are captured by the universal operator and the existential operator, respectively. They operate on propositional functions, of which those are necessarily true that are satisfied by all values of the bound variable 'x'. Those propositional functions are possible that are satisfied by some value vii

S. Knuuttila (ed.), Reforging the Great Chain ofBeing, vii-xiv. Copyright © 1980 by D. Reidel Publishing Company. viii INTRODUCTION of 'x'. If the bound variable 'x' ranges over moments of time, then we have the presupposition mentioned. According to Becker, this is one possible way of understanding the statis• tical interpretation of modal notions, and he refers to the following passage in Kant: "The Schema of possibility .... is the determination of the re• presentation of a thing at any time whatsoever. The schema of reality is the existence at a given time. The schema of necessity is the existence of an object at all times." (, Critique of Pure , transl. by F. Max Miiller, Doubleday, Garden City, N.Y. 1966, p. 125). This is not the only explication Becker offers to his statistical interpreta• tion of modal calculi. But on this interpretation modal notions are reduced to extensional terms, and hence similar ideas were not uncommon among the logical positivists. (For some examples see H. Poser, 'Das Scheitern des logischen Positivismus an modaltheoretischen Problemen', Studium Generale 24 (1971), pp. 1522-1535). Other examples of this line of thought can be easily found in the works of . In 'The Philosophy of ' (1918) he writes: "One may call a propositional function necessary when it is always true; possible, when it is sometimes true; impossible, when it is never true." (See Bertrand Russell, Logic and Knowledge. Essays 1901-1950, edited by R. C. Marsh, Allen & Unwin, London 1956, p. 231). Russell says that he gets the notion of existence out of the notion of sometimes "which is the same as the notion of possible". So by saying that unicorns exist one means that "x is a unicorn" is possible i.e., there is at least one value of x for which this is true. If there is no such value, then the propositional function is impossible. (Op. cit. pp. 231-233). It is then contended that ordinary uses of the word 'possible' are derived from the idea that a propositional function is possible, when there are cases in which it is true. This is elucidated by discussing the (rather ambiguous) "It is possible it may rain to-morrow". According to Russell this means that "It will rain to-morrow" belongs to "the of propositions 'It rains at time t', where t is different times. We mean partly that we do not know whether it will rain or whether it will not, but also that that is the sort of that is quite apt to be true, that it is a value of a propositional function of which we know some value to be true." (Op. cit. pp. 254-255. For Russell's views, see also G. H. von Wright, 'Diachronic and Synchronic Modalities', Teorama IX (I979), pp. 231-245.) It is easy to see why Russell must say that modal notions are attributes of propositional functions and not of propositions. He trusts in the analogy between modal notions and those expressing historical frequency without INTRODUCTION ix considering the idea of alternatives of a temporally defmite case. On his interpretation the statistically understood modal notions refer to realization in the actual history, and when temporally defmite events or propositions are discussed, they as such seem to have no modal status. It is typical that in the above quotation the focus of attention is changed from the temporally defmite proposition to a form where there is a blank to be filled by a temporal specification. It is clear that the alleged possibility of the latter, i.e. the that it is true for some moments of time, does not say anything about the possibilities at the moment to which the original proposi• tion refers. Contrary to what Russell says, it does not appear to be typical for the contemporary understanding of possibility that it refers to types of states of affairs exemplified in the actual history. The current ordinary understand• ing of modality is rather codified, for instance, in what is generally known "as possible worlds . According to it the logic of modal notions can be spelled out only by considering several possible worlds and their relations to each other at the same time. For example, Op is true in the actual world if there is a in which p is true. There is no demand that the pos• sible world in which p holds true should sometime be actual in the real his• tory. (See, e.g., laakko Hintikka, Models for Modalities, D. Reidel, Dordrech t 1969). Although there are in contemporary philosophy approaches to the logic of modal notions analogous to those mentioned above, they have mainly lost their attraction as theories about modality. It is widely thOUght that when modal notions are reduced to extensional terms which classify events of the actual history, the resulting idiom does not speak about modality at all. Be this as it may, it seems to be a historical fact that certain kinds of reductionistic statistical interpretations of modal terms enjoyed a prominent status among the presuppositions of Western thought from Aristotle until the late thirteenth century. This was realized by C. S. Peirce, who wrote in his article 'Modality' for Baldwin's Dictionary of Philosophy and Psychology (MacMillan, Gloucester, Mass. 1901) as follows: "The simplest account of modality is the scholastic, according to which the necessary (or impossible) proposition is a sort of universal proposition; the possible (or contingent, in the sense of not necessary) proposition, a sort of particular proposition. That is to assert 'A must be true' is to assert not only that A is true but that all propositions analogous to A are true; and to assert 'A may be true' is to assert only that some proposition analogous to A is true. If it be asked what is there meant by analogous propositions, the answer is - all those of a certain class which the conveniences of reasoning establish." I don't comment here on Peirce's own interpretation of "the scholastic x INTRODUCTION account of modality"; it is not scholastic. But it is interesting that he refers to the scholastic theory in which 'necessity' and 'possibility' were defmed in terms of "true in every case" and "true in some cases", respectively. In 1936 Arthur O. Lovejoy published his William James Lectures delivered at Harvard University in 1933 under the title The Great Chain of Being: A Study of the History of an Idea, (Harvard University Press, Cambridge, Mass. 1936). In this famous study of the history of certain much attention is paid to the so-<:alled Principle of Plenitude, according to which no genuine possibility remains unrealized. Lovejoy treats this principle merely as a corollary to the idea of the Great Chain of Being, i.e., the idea that the selec• tion of different kinds of individuals as are exemplified in actuality is the fullest possible one. FollOwing his general methodological guidelines, he also argues that the Principle of Plenitude is a perennial idea which different thinkers have built into their systems in different ways. In fact the Principle of Plenitude, when it is understood as a certain kind of relation between possibility and actuality, can have many various roles in philosophical argu• mentation. It is, e.g., contained in reductionistic statistical modal theories described above. It can be shown that Lovejoy's reliance on the assumption of 'unit ideas' prevented him from realizing the variety of ways in which this alleged 'unit idea' figures in the history of Western thought. The methodological shortcomings of Lovejoy's attempt are pointed out in Jaakko Hintikka's essay 'Gaps in the Great Chain of Being: An Exercise in the Methodology of the History of Ideas' (below pp. 1-17). It serves as a general introduction to the topics of this book. Hintikka calls attention to different traditions and lines of thought which in fact imply the Principle of Plenitude but which were not dealt with in Lovejoy's study. If the Principle is under• stood as a possible ingredient of a theory of modal notions, we can use it as a theoretical in the study of the history of modal notions. Then we will fmd instances of it as more as less explicit parts of various doctrines in the history of thought. Many different starting points may yield the same opinion that each possibility must ultimately bear fruit. Perhaps the most important single mistake in Lovejoy's book is his claim that the Principle of Plenitude was explicitly denied by Aristotle. This view also made him blind to certain peculiarities of the interpretation of modal notions in the Aristotelian tradition. In his many studies on Aristotle's theory of modality Hintikka has maintained that the principle is in fact included in all of Aristotle's modal . Some of his evidence against Lovejoy's view of Aristotle is collected in the article 'Aristotle on the Realization of Possibilities in Time' included in this volume (pp. 57-72). INTRODUCTION xi

In his book Lovejoy referred to certain passages in which Aristotle seems to maintain that some possibilities can remain unrealized. This could be called the Principle of Scarcity. In his interpretation Hintikka maintains that Scar• city does not pertain to total possibilities in Aristotle. It is trivially true that there are all sorts of unrealized potentialities according to Aristotle. For instance, he distinguishes what might be called active potencies from passive ones. If the former is an efficient cause and the latter a material cause, it is of course possible that in an individual case the material cause is actual but that the efficient cause is not present. In this sense there can be unrealized partial potentialities or partial possibilities. But because neither sort of poten• tiality alone can initiate a change or motion, a partial possibility cannot be actualized in so far it is only a partial possibility. Because a partial possibility cannot, as such, be actualized, it cannot be a genuine possibility according to Aristotle. In his paper 'Aristotle and the Priority of Actuality' R. M. Dancy discusses the respective roles of the Principles of Plenitude and Scarcity in Aristotle's (pp. 73-115). He shows that, in the argument for the priority of actuality on which the doctrine of the eternity of the world is based, Aristotle uses both the Principle of Plenitude as well as the Principle of Scarcity. They do not contradict each other in Aristotle, Dancy argues, for all that Scarcity tells us is that a potentiality need not, at any given time, be actualized. Plenitude tells us that every possibility must sooner or later be realized. In this form both principles go together with the statistical inter• pretation of modal notions. In both of the works mentioned Hintikka doubts Lovejoy's claim that Plato adopted the Principle of Plenitude without qualifications. Many other scholars have also been skeptical about this view of Lovejoy's. In his paper 'Empty Forms in Plato' Michael Rohr discusses the alleged counter-evidence, especially the opinion according to which Plato thought that there are empty forms (pp. 19-56). Rohr argues that in Plato there are no forms which have only the forms themselves as instances, i.e., that there is no form which is never instantiated by any particulars. Although some forms may be temporally empty, all forms have as many instances as they can. His careful argumenta• tion lends interesting support to Lovejoy's somewhat sketchy thesis and offers challenges to further studies of Plato's modal ideas. Aristotle regarded the typical form of singular declarative statements as temporally unqualified. Hintikka has maintained that the statistical model of modality in Aristotle is connected with his preference for this type of sentences, which contain a reference to the time of utterance as a part of their . On the statistical interpretation of modality in Aristotle, xii INTRODUCTION necessary statements are identified with those that are true whenever uttered, possible statements with those that are sometimes true, and impossible ones with those that are never true. In my paper 'Time and Modality in Scholas• ticism' I explain how this model was introduced into scholastic thought and how it was used in it (pp. 163-257). In particular, I discuss certain common types of argument in which the Principle of Plenitude in its Aristotelian form is employed. I also mention some early deviations from the acceptance of this principle in medieval thought. In the latter part of my paper I claim that an important change in the history of modal theories took place in the beginning of the fourteenth century. In Duns Scotus the meaning of modal notions is connected with the idea of considering different alternative states of affairs at the same time. In the late medieval modal theory, to be seen already in Duns Scotus' thought, the domain of possibility is accepted as an a priori area of conceptual consistency. It is then divided into different classes of compossible states of affairs of which the actual world is one. Of logical possibilities some are mere conceptual possibilities and some are real alterna• tives of the actual world. The Principle of Plenitude does not hold of either group of possibilities. The Principle of Plenitude was usually not accepted in the Middle Ages without qualification, because it was thought to restrict God's power and freedom. As I argue in my paper, this did not belie the widespread acceptance of a statistical interpretation of natural possibilities in early medieval thought. However, Eileen Serene argues in her paper 'Anselm's Modal Conceptions' that the Principle of Plenitude is not present in Anselm's modal theory (pp. 117-162). Anselm's treatment of modal notions is an early example of a theory in which the Principle of Plenitude is ignored. (There is some evidence that certain Stoic may have denied the principle; for a recent discussion of some examples see D. E. Hahm, The Origins of Stoic Cosmology, Ohio State University Press, Columbus, Ohio 1977, pp. 103-107, 260-266.) It is also interesting that Anselm's modal theory seems to have nothing in common with the ideas of the modem modal theory developed in the early fourteenth century. Anselm's theory of modal notions proper is as reduc• tionistic as the statistical ones are. As Serene points out, the literal sense of necessity is constraint or force and the literal sense of possibility is capacity or potency. Serene shows that Anselm in fact becomes involved in many difficulties when he tries to interpret different uses of modal notions with the help of those basic notions. Perhaps the most interesting of those problems are formulated in Anselm's late works. He was, e.g., worried about cases in which a possibility-predicate is ascribed to a nonexistent subject. In her paper INTRODUCTION xiii

Serene tries to Anselm's solution which is not to be found in the texts known to us. The fourteenth century modal theory mentioned above has some striking similarities with l..eibniz's theory of modality discussed by Hintikka in his paper 'Leibniz on Plenitude, Relations, and "the Reign of Law" , (pp. 259- 286). l..eibniz's theory of complex predicates, his idea of individuals reflecting the whole universe, and certain other doctrines treated in the article can be understood as attempts to answer some of the philosophical problems con• nected with the principal idea according to which the domain of possibility is structured by sets of relational compossibilities. Although l..eibniz's modal theory may be in many ways objectionable, Hintikka shows in his paper how the new way of treating modality originated in the fourteenth century is interwoven with the development of the idea of mathematical law of in early modern science and with the development of the concepts of relation and function. Traditional presuppositions did not, however, disappear as soon as the new ideas were introduced. Hintikka refers to Hobbes, Descartes, and Spinoza, all of whom accepted at least partially the idea that genuine possibilities cannot remain unrealized forever. Lovejoy presents a vivid picture of the popularity of this idea in the early modern period. In their joint paper Hintikka and Heikki Kannisto discuss Immanuel Kant's attitude toward the Principle of Plenitude (pp. 287 -308). In the first period of his thought Kant accepted the principle in a traditional way for natural possibilities and denied it with respect to God's possibilities in a good scholastic manner. In his early critical philosophy Kant denies the principle, but ironically enough his theory of the categories of human perception and thought lead him to accept a view very similar to that of . According to Thomas there are unrealized Divine possibilities, but it does not belong to the epistemic capacities of men to know what those unrealized possibilities are. Similarly, in Kant, the noumenal possibilities which might overthrow the Principle of Plenitude are beyond the realm of human understanding. For phenomenal possibilities (possibilities of experience), Kant came back to something close to the acceptance of the principle. The many-faceted role of the Principle of Plenitude in l..eibniz and Kant is spelled out more fully in the two papers just mentioned. They illustrate vividly its connection with a large number of other important philosophical ideas. These connections make the Principle of Plenitude an exceptionally useful focal point of a close study of the history of ideas. In spite of its methodological shortCOmings and historical mistakes Lovejoy's The Great xiv INTRODUCTION

Chain of Being is a success because of its author's realization of the uses of this focal point. So it is proper, if not to re-forge literally the Great Chain of Being itself, at least to re-evaluate and to reconstruct the argument of The Great Chain of Being. Jaakko Hintikka's 'Gaps in the Great Chain of Being: An Exercise in the Methodology of the History of Ideas' originally appeared in the Proceedings and Addresses of the Americal Philosophical Association, Vol. XLIX (1976), pp. 22-38. It has been revised for publication. 'Aristotle on the Realization of Possibilities in Time' appeared as the fifth chapter of Hintikka's book Time and Necessity: Studies in Aristotle's Theory of Modality, Clarendon Press, Oxford 1973. Hintikka's 'l.eibniz on Plenitude, Relations, and "the Reign of Law'" appeared in Harry G. Frankfurt (ed.), Leibniz: A Collection of Critical Essays (Modern Studies in Philosophy), Doubleday, Garden City, N.Y. 1972, pp. 155-190. The joint paper by Jaakko Hintikka and Heikki Kannisto has been published in Philosophic Exchange, Vol. 2 (1976), pp. 69-85. These papers are reprinted here without major changes. An abstract from Michael Rohr's Empty Forms in Plato appeared in Archiv fur Geschichte der Philosophie 60 (1978), pp. 268-283. These papers are reprinted with the permissions of the relevant authors, publishers, and editors. The permissions are gratefully acknowledged.

SIMO KNUUTTILA