From Plato to Platonism

Chapter 6: The Academic Skeptics

As we saw in the first chapter, one of the elements of UP is antiskepticism. Aristotle’s testimony strongly suggests that Plato was, for virtually his entire career, wedded to the view that knowledge (ε ’πιστήμη) is possible and that it is not of sensible but rather of ‘separate’ intelligible entities. It seems a straightforward matter to characterize the Skeptics’ position as the contradictory of the claim that knowledge is possible. But in fact many things that both Plato and Skeptics actually say about knowledge should give us pause. First, in Phaedo Socrates claims that “if it is not possible to know anything purely while we are embodied, either nowhere is knowledge possessed or it is only for the dead.”1 It is, I think, a serious mistake to take ‘know purely’ to imply that there is a type of knowledge that is ‘impure.’ This is the case not merely because it would contradict Aristotle’s testimony. More important, if, as Plato himself argues in Republic, knowledge is of Forms, a putative ‘impure ’ knowledge of Forms would be something other than ε ’πιστήμη. Not only is there not a single word in the entire Platonic corpus to suggest that there is a mode or cognition of Forms other than ε ’πιστήμη (or its equivalent νόησις), but the argument in Theaetetus that true belief cannot be knowledge—even if true belief is ‘supplemented’ by some sort of λόγος—is sufficiently broad in its scope that there is no room left over for a mode of 1. Phd. 66E4–6: ε’ ι γὰρ μὴ οι ‛ ˜όν τε μετὰ του̃ σώματος μηδὲν καθαρω̃ς γνω̃ναι, δυοι̃ν θάτερον, ’ ὴ ου ’ δαμου̃ ε ’´στιν κτήσασθαι τὸ ε’ ιδέναι ’ ὴ τελευτήσασιν. Cf. D7–E2, 65E1–4, 67A2–6. In the context of the passage, it is clear that the words used here for ‘knowledge’ (γνω̃ναι, ε’ ιδέναι) are being used for the ‘highest’ form of cognition, knowledge or wisdom (σοϕία). Chapter 6 The Academic Skeptics 164 Chapter 6 cognition of Forms that is not ε ’πιστήμη and not belief.2 The words “know purely,” then, should be understood as suggesting that the ne plus ultra of cognition alone is not available to embodied individuals.3 And yet, not too much after this passage we have the Recollection Argument for the immortality of the soul, an argument the principle conclusion of which is that we do in some sense have ε ’πιστήμη; for if we did not, we could not make the judgments about the relevant deficiency of instances of Forms in the sensible world. It seems evident that the ε ’πιστήμη we perhaps cannot possess while embodied is different in some way from the ε ’πιστήμη we must possess if we are to be able to make judgments like “these equal things are deficiently equal.” The relevant distinction is made in Theaetetus. This is the distinction between “possessing” (κεκτήσθαι) knowledge and “having” (τὸ ε ’´χειν) it.4 This is a distinction between the presence in the knower of that which is knowable (‘possessing’) and the awareness of the presence (‘having’). Deploying this distinction in the argument in Phaedo, we would say that we must ‘possess’ knowledge in order to make judgments about the deficiencies of sensibles, whereas ‘having’ knowledge is definitely problematic for embodied individuals. If Plato’s antiskepticism regards only the having of knowledge, it remains an open question as to whether he concedes the Skeptics’ claim with regard to the impossibility of possessing knowledge. The account in Republic of the education of the rulers culminating in knowledge via a vision of the Idea of the Good at fifty years of age only slightly mitigates the pessimism of Phaedo.5 At most, this knowledge is possible only for the elite few and then only near the end of their lives. For many scholars, the temptation to discount Plato’s epistemic rigorism is considerable. One way of doing this is to insist that ε ’πιστήμη or a kind of ε ’πιστήμη is possible for sensibles as well as for intelligibles.6 Apart from the fact that there is virtually nothing in the texts of Plato 2. See Gerson 2009, 44–55. The mode of cognition that Plato calls διάνοια (‘understanding ’ or ‘thought’) in Republic is clearly not the required tertium quid. It is not a kind of ε ’πιστήμη. Cf. 533C7–E2. 3. Cicero, De nat. deo. 1.11, refers to Socrates as the originator of the idea of refraining from judgment and Arcesilaus as having revived it (repetita). This implicitly drives a wedge between Socrates and Plato, but only if we identify Socrates not with the historical figure, but, rather arbitrarily, with the figure in the ‘aporetic’ dialogues alone. Shields (1994, 343–45) argues that Arcesilaus, “by extending certain Socratic practices” in what Shields assumes to be the early dialogues, can be understood...