STOIC RATIONALISM ______________________________________________ A Thesis presented to the Faculty of the Graduate School University of Missouri – Columbia _______________________________________________________ In Partial Fulfillment Of the Requirements for the Degree Masters of Arts _______________________________________________________ by DR. HENRY DYSON Dr. Daniel Hooley, Thesis Supervisor JULY 2005 ACKNOWLEDGEMENTS I would like to thank the Department of Classical Studies and Ancient Studies Program for their generous funding and support during my time at the University of Missouri. I am especially grateful to Daniel Hooley for his advice, encouragement, and direction of this thesis. I would also like to thank my departmental committee members, David Schenker and Ray Marks, and external readers, Andrew Melnyk from the Philosophy Department at the University of Missouri and John M. Cooper from the Program in Classical Philosophy at Princeton University, for their helpful comments on the penultimate draft. I owe a special debt of gratitude to Brian Kierland for many hours of engaging conversation that helped me formulate and clarify the main points of my argument. Finally, I would like to thank Osama, Bilal, Issam, and the rest of the crew at Coffee Zone (where the majority of this thesis was actually written). And as always, my greatest thanks go to my wife, Melissa, for her loving support in so many areas of life that make my intellectual pursuits worthwhile. ii TABLE OF CONTENTS ACKNOWLEDGEMENTS…................................................................................ ii LIST OF ABBREVIATIONS ................................................................................ iv ABSTRACT…........................................................................................................ v Chapters INTRODUCTION: EMPIRICISM AND RATIONALISM IN HELLENISTIC PHILOSOPHY…..................................................................................................... 1 1. SOME PRELIMINARY DISTINCTIONS CONCERNING EMPIRICISM AND RATIONALISM….............................................. 14 1.1 The Definitions of Epistemological Empiricism and Rationalism 1.2 The Separability of Psychological and Epistemological Rationalism 1.3 Criteria for Empiricist and Rationalist Readings of Stoic Epistemology 2. CRITICISM OF EMPIRICIST READINGS OF STOIC EPISTEMOLOGY…............................................................................. 28 2.1 Perceptual and Rational Comprehension 2.2 Refinement of the Criterion for Empiricist Readings 2.3 Criticism of the Inferential Reading 2.4 Criticism of the Causal Reading 3. PROLEPSIS AND A PRIORI KNOWLEDGE IN STOICISM........... 59 3.1 Concepts and Conceptions 3.2 Concepts and Conceptual Objects 3.3 The Formation of Concepts, Conceptions, and Conceptual Objects 3.4 The Tacit Function of Conceptions in Human Rationality 3.5 Two Conceptions of Conceptions: Prolepses and Suppositions CONCLUSION: THE HISTORICAL PLACE OF STOIC EPISTEMOLOGY..... 102 BIBLIOGRAPHY…................................................................................................ 113 iii LIST OF ABBREVIATIONS Acad. Cicero: De Academica APo. Aristotle: Analytica Posteriora CN Plutarch: De communibus notitiis contra Stoicos DA Aristotle: De anima DL Diogenes Laertius: Lives of Philosophers Did. Alcinous, Didaskalias tôn Platônos dogmatôn Diss. Epictetus: Dissertationes EM Seneca: Epistulae Morales Fin. Cicero: De finibus Gorg. Plato: Gorgias IG Inwood and Gerson: Hellenistic Philosophy: Introductory Readings In An. Simplicius: In Aristotelis De Anima In Cat. Simplicius: In Aristotelis Categorias In Met. Syrianus: In Aristotelis Metaphysica In Tim. Calcidius: In Platonis Timaeum Leg. Cicero: De legibus LS Long and Sedley: The Hellenistic Philosophers M Sextus Empiricus: Adversus Mathematicos Met. Aristotle: Metaphysica ND Cicero: De natura deorum Parm. Plato: Parmenides Plac. Ps-Plutarch: Placita Phd. Plato: Phaedo Phdr. Plato: Phaedrus Prot. Plato: Protagoras PH Sextus Empiricus: Pyrrhoniae hypotyposeis PHP Galen: De placitis Hippocratis et Platonis Rep. Plato: Republic RN Lucretius: De rerum natura SA Plutarch: De sollertibus animis Sign. Philodemus: De signis Soph. Plato: Sophist SR Plutarch: De Stoicorum repugnantiis Stob. Stobaeus: Eclogae SVF Von Arnim: Stoicorum Veterum Fragmenta Theat. Plato: Theaetetus iv ABSTRACT The prevailing scholarly opinion is that the Stoics are empiricists rather than rationalists. Empiricism is a branch of epistemology that gives priority to sense-perception whereas rationalism gives priority to reason’s grasp of necessary truths. One should distinguish, however, between psychological theories of concept-formation and epistemological theories of justification. The Stoics are both epistemological rationalists and psychological empiricists. I support this claim by criticizing various empiricist readings of Stoic epistemology. I argue that these readings do not adequately account for the Stoics’ doctrine of rational comprehension. I provide further support by explaining how a particular type of conception, called ‘prolepsis,’ is both derived from sense-perception and grounds reason’s a priori comprehension of necessary truths. I conclude by exploring the historical implications of this reading of Stoic epistemology. I argue that, contrary to the prevailing opinion, the Stoics see themselves as belonging to the same rationalist tradition in epistemology as Plato. v INTRODUCTION: EMPIRICISM AND HELLENISTIC PHILOSOPHY Scholarly discussions of Stoic epistemology generally present their doctrines in the context of their debate with the Academic and Pyrrhonian skeptics. One of the main focal points of this debate is the existence of the so-called “comprehensible presentation” (phantasia katalêptikê). This is defined as a presentation that “arises from what is [the case] and is stamped and impressed exactly in accordance with what is [the case], of such a kind that it could not arise from what is not [the case].”1 In other words, the comprehensible presentation is one that presents the corresponding state of affairs in such a way that its propositional content could not be false. Assent to such a presentation produces the cognitive state the Stoics call “comprehension” (katalêpsis) because it allows one to grasp a fact about the world with absolute certainty. Comprehension is the basic unit of knowledge and criterion of truth in Stoic epistemology. By comparison with comprehensions other beliefs may are judged to be true or false; and scientific understanding (epistêmê) is defined as a mutually supporting system of comprehensions.2 The Academic and Pyrrhonian skeptics deny that there are any presentations that meet these requirements for comprehension. There is no presentation, they say, which is so clear that it could not come from some other state of affairs.3 In support of this counter-argument they offer the standard skeptical examples of perceptual illusions, hallucinations, and the indiscernibility of twins and eggs. They conclude that certainty is not possible and that knowledge in the strict sense defined by the Stoics does not exist. 1 Sextus M 7.248. All translations are from LS (1987) unless otherwise noted, although I have made occasional alterations. 2 Cf. Stob. 2.73,16-74,3. 3 Cf. Cicero Acad. 2.78 and Sextus M 7.251-2. 1 Consistent with the Academics’ dialectical method, the basis for this skeptical conclusion is one of the Stoics’ own arguments. Indeed, it seems to have been one that Zeno originally posed against the dogmatic Platonists of the late 4th century.4 According to Zeno, sense-perception is the link between the mind and the world and is thus the source for all knowledge. He then asserted the following counterfactual conditional: if sense-perception were not certain, then no knowledge would be certain. Since the Stoics and Platonists agree that certainty is a necessary condition for knowledge, the consequent amounts to a denial of the existence of knowledge. Of course, both Zeno and his Platonic opponents believe that knowledge and certainty are possible. The Platonists, however, say that only reason’s comprehension of intelligible forms by reason is capable of certainty. They relegate the grasp of sensible things by sense-perception to the realm of mere opinion or belief (doxa). Zeno used the above conditional to argue via modus tollens that sense-perception is indeed capable of certainty.5 Arcesilaus, in turn, used the same conditional to arrive at his skeptical conclusion via modus ponens. Sense- perception is not capable of certainty, he argues, since there are no comprehensible presentations. Thus, knowledge in the strict sense is not possible.6 It has been a commonplace of scholarship for at least the last century that the Stoics are empiricists.7 Given the emphasis placed on sense-perception, both by Zeno himself and by his skeptical opponents, this characterization is not surprising. It is especially associated with two aspects of the Stoic doctrine. First, we are told by 4 Cf. Cicero Acad. 1.40-1. 5 The same argument structure can be observed in Epicurus and has roots in Democritus. 6 Cf. Cicero Acad. 2.77-8. 7 Cf. in particular Annas (1981, 85 and 93-4), (1990) and (1992, 86-7), Hankinson (2003, 63-4 and 76), Long (1974, 125), LS (1987, 1:239), Schofield (1981, 289), Sedley (1980, 13-4), and Sharples (1996, 11- 2). The issue was also debated in the 19th century. Cf. Bonhöffer (1890) for a summary of the various positions. 2 numerous sources that the