In the past three decades, contemporary Aristotelians have posed effective challenges to liberal theory by stressing the importance of citizenship, political virtue, civic prudence, and the political passions. Without denying the manifest goods made possible by the liberal political order, neo-Aristotelian theorists have argued that we can improve our understanding of political life by directing attention to the resource-rich tradition of Aristotelian political science. Dissatisfied with the apathy of liberal citizens, for example, Susan Collins has revived a specifically Aristotelian model of citizenship that is the product of authoritative civic education focused on seeking the human good. Gerald Mara argues that the Rawlsian and Habermasian vision of “public reason” and the autonomy of political agents can be helpfully supplemented by the Aristotelian exploration of the passions that shape public rhetoric and communication. Ronald Beiner has redeployed the Aristotelian concepts of eudaimonia, phronēsis, and virtue in order to criticize the subjectivism of liberal “values” and the emptiness of liberal neutrality. Beiner's view is that active, Aristotelian citizenship focused on working out a shared human destiny is the best way to realize, in practice, our higher and distinctively human capacities for judgment. Stephen Salkever theorizes an Aristotelian “ethics of natural questions” as a deliberative model superior to that offered by the typically Kantian exponents of deliberative democracy, such as Habermas.

PYRRHO AND THE BEGINNING OF SCEPTICISM

Pyrrho of Elis (ca 360–270 bce), painter, student of atomism, of Indian philosophy, and certifiable eccentric was taken by the ancients to be the founder of scepticism. As usual, things are not quite so straightforward. The first sceptic of the philosophical schools was the Academic Arcesilaus (316/15–241/240 bce), perhaps some two generations younger. It is not implausible that Arcesilaus was inspired by Pyrrhonian philosophising but there is no direct evidence that he was. The Academic Aenesidemus' ‘Pyrrhonian revival’ in the first century bce certainly stakes itself to a Pyrrhonian inspiration, as indicated by two of the titles of his works – Pyrrhonian Discourses and Outline Introduction to Pyrrhonian Matters. It is, though, given the paucity of evidence, difficult to judge to what extent Pyrrho was more than a vivid personage whose name and notable character were his sole contributions to later scepticism.

In any case, the first century bce or ce Peripatetic philosopher Aristocles of Messene wrote an extensive and, as far as we can judge from the remaining fragments, acute history of philosophy in which he tries to summarise Pyrrho's philosophical position. The account is preserved for us by Eusebius, the fourth century bishop of Caesarea in his Praeparatio Evangelica. It contains most of what we know of Pyrrho apart from his colourful life and will serve as a useful starting-point for my account.

INTRODUCTION

In Plato's dialogues and according to Aristotle's testimony regarding his philosophical development, Plato's engagement with his predecessors' thinking about epistemological and metaphysical issues is nothing less than pervasive. At virtually every turn, we see him wrestling with the distinction between knowledge and belief, appearance and reality, epistemic and non-epistemic appearances and so on. He no doubt started with the universal Presocratic assumptions that knowledge is a real, not merely notional achievement, that it is more than merely belief, and that its desirability is manifest. As we shall see, however, he is prepared to scrutinise these assumptions from various points of view. His conclusions about the nature of knowledge are inseparable from his conclusions about what is knowable. Plato's successors in antiquity, despite revisiting the storehouse of Presocratic wisdom, are constantly grappling with these conclusions.

The value of knowledge over belief underlies the so-called early or Socratic dialogues in a straightforward way. Socrates' interlocutors, such as the preternaturally obtuse Euthyphro, typically believe that they know what a pious or just or temperate deed or person is. Euthyphro is confident that in prosecuting his father for the negligent homicide of a slave, he is engaging in a pious action. Socrates seems to assume that if one does not know what piety is, one is hardly in a position to persist in this confidence. Conversely, if one does possess this knowledge, one is in a powerful, if not invincible, position to acquire true beliefs about putative cases of piety.

INTRODUCTION

The term ‘Neoplatonism’ is an eighteenth-century label coined by German scholars (‘Neuplatonismus’) used pejoratively to indicate unwholesome contaminations of the pure stream of ancient Hellenic thought. I use that term here simply to refer to the last phase of ancient Greek philosophy, beginning with Plotinus (204–270 ce) and ending effectively with the pervasive domination by Christianity of the Greek world in the sixth century. I focus primarily on Plotinus, the ‘founder’ of Neoplatonism, because of his explicit engagement with the entire history of philosophy as he knew it, from the Presocratics up to contemporary Peripatetics. As we shall see in a moment, Plotinus provides one dogmatic response to the sceptical onslaught. In particular, it is, not surprisingly, a response made from a Platonic perspective. Precisely because Plotinus was so conscious of the ongoing eight-hundred-year long dialogue among the Greek philosophical schools, his dogmatic response is really something quite original. In regard to epistemology, it is a response steeped above all in Aristotle's analysis of cognition. Plotinus was more than willing to invoke Aristotle's assistance on behalf of a defence of Platonism against sceptical attacks on the possibility of knowledge and rational belief. Although Plotinus is critical of Aristotle on numerous matters, there is no indication that this critical stance included epistemology. Plotinus' originality lay in an attempt to articulate the position with regard to knowledge and belief that I outlined in the first chapter.

The present book has its genesis in my reflecting on the millennium-long dialogue in antiquity concerning the nature of knowledge. Amidst the complex ongoing disputes, there was implicit agreement that the very possibility of philosophy stood or fell on the possibility of achieving wisdom, the highest or best type of knowledge. The particular structure of the book arises from my conviction that contemporary epistemology stands to benefit from bringing ancient views about knowledge into the discussion, and that this is so despite the vast scientific gulf that separates them from us.

I am deeply grateful to G. R. F. Ferrari and Catherine Osborne for their invitation to publish my book in the series of which they are the general editors. Their gracious support and criticism of earlier drafts have been enormously helpful. I have also benefited from the advice and criticism of Panayot Butchvarov, Franco Ferrari, Francesco Fronterrota, Christopher Gill, Brad Inwood, James Lesher, David Reeve and Alan Silverman, each of whom read all or part of the work with a critical eye. The errors from which they saved me will, I am relieved to say, never see the light of day. As for those errors from which they could not save me, try though they may, I can only say that it might afford these eminent scholars and philosophers some measure of satisfaction to correct them in public now that they are in print. As always, I am most grateful to my best critic, my wife Asli Gocer.

INTRODUCTION

In this chapter, I turn to the responses made to Plato and Aristotle and, indeed, to the entire epistemological tradition by those in the first and second generations after Aristotle. Specifically, I will focus on Epicurus and the members of the so-called Old Stoa, Zeno, Cleanthes and Chrysippus. My justification for treating together two schools of philosophy that are deeply divergent in many ways is that they share a type of naturalism in epistemology that is self-consciously materialist. Owing to the fragmentary nature of our evidence and to considerations of space, I am going to try to express what I take to be the common ground among Epicureans on the one hand, and Stoics on the other, relating to epistemology. To this end, I shall make use of relatively late testimony by friends and foes alike of these two great schools of ancient philosophy. I hope that suppressing any of the philosophical differences that might have existed between, say, Chrysippus and Zeno will not compromise my basic account.

We saw in the last chapter that Aristotle criticised his predecessors for failing to distinguish thinking and sense-perception. They did so, says Aristotle, because they believed that (1) sense-perception is corporeal; (2) reality is corporeal and (3) cognition must be by that which is the same sort of thing as that which is cognised. So, (4) thinking, like sense-perception, must be corporeal. Aristotle does not dispute (1). His reaction to (2) and (3) is nuanced.

A book on ancient epistemology is sure to face the suspicion that its subject is only of antiquarian interest. What, after all, could ancient epistemologists teach modern practitioners in the field? The prospects for a positive answer to this question might, to the untutored eye, seem to dim further when we realise that ancient epistemology is a form of naturalism, that is, an account of cognition in general rooted in an understanding of the natural world to which humans belong and also from which they somehow stand apart as observers or thinkers. Reasonably enough, one might suppose that an antiquated view of nature would inevitably produce a view of human knowledge destined to be antiquated as well. The viability of ancient epistemology will depend on how persuaded we are that epistemology ought to be assimilated to natural science. Modern philosophers are divided over this question. It would, however, be a mistake to try to make a case for the continuing relevance of ancient epistemology by treating it as a forerunner of contemporary non-naturalism, roughly, the view that epistemology is largely a matter of logic and semantics and not a legitimate branch of natural science. In fact, ancient epistemology is not accurately represented either as an obsolete or inchoate version of modern naturalism or as a version of the non-natural ‘criteriological’ approach. It constitutes a third approach.

NATURALISM REDIVIVUS

I have argued that the ancient philosophers generally treated knowledge and belief naturalistically. The non-naturalistic or criteriological approach of the Standard Analysis is aborted in Plato's Theaetetus, although the Standard Analysis itself lives on in its subsequent application to rational belief. If knowledge is a natural feature of human life like digestion or pregnancy, it would seem to be available for empirical scientific investigation. If that is so, ancient epistemological naturalism will find itself at a disadvantage, to put it mildly. For to admit the relevance of biology, neurophysiology, psychology and so on to the study of epistemology seems to ensure that ancient naturalism is doomed to melt into the deep background of historical curiosities. In this light, if one rejects a contemporary version of naturalised epistemology, the only plausible alternative would seem to be some non-naturalised approach, most appropriately rooted in logical or linguistic analysis and in the evaluative use of a certain class of terms and concepts. An analysis of how our words or concepts are used or even how they ought to be used need not have anything to fear from the deliverances of modern empirical science. By contrast, insofar as ancient epistemology is supposed to be dependent on ancient science, its subsequent obsolescence appears to be inevitable. I have in the preceding chapters tried to cast some doubt both on the supposition that ancient epistemological naturalism is susceptible to refutation by the claims of empirical science and on the perhaps more egregious error of supposing that ancient epistemology is not a form of naturalism.

INTRODUCTION

Discussions of Aristotle's epistemology typically begin with the explicit or implicit assumption that, owing to his rejection of Plato's theory of Forms, Aristotle's thinking about knowledge and the objects of knowledge must be fundamentally different from Plato's. Indeed, if Forms do not exist, and if the motivation for radically separating knowledge and belief is just that cognising Forms is entirely different from cognising sensibles, that motivation is evidently not going to be shared by Aristotle. And yet Aristotle does repeatedly say, for example, that there is no knowledge of the objects of belief. He even maintains that there is no knowledge ‘by means of sense-perception’. So, one may well wonder whether Plato's point about the separation of knowledge and belief is a point that depends on a theory about Forms as opposed to a theory about the difference between what is intelligible and what is sensible generally. In the latter event, it is all the more interesting if it turns out that Aristotle – despite his substantial disagreements with Plato – agrees with his master's basic epistemological doctrines.

A terminological note is in order. In Republic as we have seen, Plato initially uses the term epistēmē for the two modes of cognition – noēsis and dianoia – in the top part of the Divided Line. He corrects this later on and limits the use of epistēmē to the highest portion, reserving the term noēsis for both.

Despite the fragmentary nature of the evidence regarding the thought of the Presocratics, there is little doubt that recognisably epistemological claims and questions arise practically simultaneously with philosophy itself. In this chapter, I will try to explain why epistemology was inseparable from the enterprise of philosophy as the ancient Greeks understood it. Among other results, I hope to show why the Sceptic Sextus Empiricus, some eight hundred years later, looking back on the entire history of philosophy as he knew it, was correct in seeing that an attack on the possibility of knowledge was virtually an attack on philosophy itself. As Sextus realised, philosophers supposed that they were aiming at wisdom and wisdom was a sort of knowledge. If knowledge is not possible, the quest for wisdom as traditionally conceived is vain.

Philosophy begins in ancient Greece with a simple hypothesis: nature (phusis) is or has an order (kosmos) or structure. If nature has an order or is structured, that order is intelligible. It is subject to reasoning or argument or understanding, in short, to logos. The idea of a kosmos is closely related to the idea of a universe or world. The idea that nature is a kosmos appears to sit closely alongside the idea that there is a single or unique order to nature. In this sense, ancient cosmological speculation from its inception bears the hallmark of scientific reductionism, that is, the operating assumption that multiple explanations are themselves ultimately reducible to or derived from a single explanation.

First distinction and delimitation of two crucial genera

First, then, in my opinion at least, one should make the following division. (27d5)

First explanation of the text: 223.5–224.17

Timaeus is a Pythagorean and right from his opening words he reveals himself as preserving the characteristic manner of Pythagorean accounts. Socrates did not expound his own opinions to others in an affirmative fashion but rather purified the conceptions of those others and so brought the truth to light in a dialectical fashion. Indeed he said to them that he knew nothing except how to offer and receive an account. Timaeus, however, because he is producing his accounts for knowledgeable men, says he is expounding his own doctrine, not bothering with the opinions of others, but pursuing the single path of knowledge. Moreover the use of [the term] opinion (27d5) is very much to the point here and consistent with what was said before. For of the rational soul in its entirety one part is intellect (nous), another is discursive reason (dianoia) and another is opinion (doxa), and of these the first is connected to the gods, the second projects the sciences, while the third provides these to others. This man, then, shows his awareness of these matters by harmonizing his own intellect with that of the gods through his prayers. This was in fact made clear by the [words] everything in conformity above all with the intellect of the gods, but also consequently with ours (27c7–d1). Through his invocations he has roused the discursive part of the soul. This is in fact shown by the [words] how I think (27d3). What remains is the opinative part [of the soul], which receives the scientific distinction (cf. 27d5) from the understanding and channels it towards others. This part (doxa) is neither ambiguous nor parcelled out over the sense-perceptible objects, nor is its form of cognition limited to mere assumptions only, but it has been filled [with information] from the intellect and the understanding, examines the demiurgic plan (logos), and distinguishes the nature of the realities.

Moreover these three aspects adequately resemble the paradigm that the speaker [Timaeus] has before him.