The Demands of Reason: An Essay on Pyrrhonian Scepticism (review)

Professional philosophy is overdue for a Pyrrhonian revival. For too long, the skeptic has been either overlooked or regarded as an object of pity (for the feebleness of his arguments) or contempt (for his appearing to thumb his nose at the canons of reason and morality). Even among the most learned and philosophically astute commentators, those who would be best positioned to develop a philosophically sophisticated and compelling interpretation of Pyrrhonism, it has found few defenders, many detractors, and has generally suffered by its having been misunderstood, caricatured, or conflated with contemporary varieties of skepticism. Casey Perin's eloquent little essay is therefore a refreshing contribution to the literature on Sextus Empiricus's Outlines of Pyrrhonism.

The focus of the essay is tightly circumscribed. In four article-length chapters, Perin is concerned "exclusively with Pyrrhonian Scepticism as it is presented by Sextus Empiricus in his Outlines," and even that treatment is, as he says, "highly selective" (1–2). He does not examine in any great detail Sextus's use of the ten modes of Aenesidemus or discuss Sextus's other skeptical treatises, nor does he explore, for instance, the rich historical context of skepticism in antiquity. Readers should not worry, however, that its brevity and selective focus in any way limit the value of this work; its implications are, on the contrary, potentially quite broad. Given Perin's philosophical objectives, the exclusivity of his treatment is entirely justified, even strategic. For there is already a sizeable body of scholarship addressing both the issues Perin brackets and those he treats. Concerning the former, there is no need to redouble the efforts of extant commentaries; concerning the latter, no bulk should be added to this body of scholarship until some very basic misconceptions about skeptical practice have been put persuasively to rest. If they can be, Pyrrhonism will appear less as a curious episode in intellectual history and more as a philosophically cogent and viable, even potentially fruitful, movement. This essay is a welcome contribution to the vigorous discussion of skepticism going on among specialists in ancient philosophy, but it should (as Sextus should) be read more widely by those interested in epistemology and moral psychology.

The Pyrrhonist claims to suspend judgment on all matters that his rivals, dogmatic philosophers, purport to investigate. His suspension of judgment brings about the tranquility (ataraxia) that Sextus describes as the motivation or the "causal principle" of skepticism (Outlines 1: 12). Critics both ancient and modern have objected that the skeptic's aim and his suspension of judgment are incompatible with genuine and rigorous rational inquiry; indeed, it has been argued that "Sextus' description of the Sceptic as engaged in the search for truth is a sham" (8). Perin's response to this charge occupies his first two chapters. Negatively, Perin's general strategy is to defend Sextus by showing how very much he can do with really very little. He draws our attention, frequently and importantly, to what Sextus does not say, clarifies what he does say, and explains, compellingly in most cases, why so many claims attributed to Sextus need not follow from the letter of the text and why it is therefore inappropriate to hold the skeptic to them. Positively, Perin then seeks to explain why someone who is able to achieve tranquility as Sextus does, by suspending judgment, would search for truth at all, and how it is possible for him to do so while employing arguments that he acknowledges to have as their conclusion "that the truth about [some] matter cannot be known" (27–32). If the argument of Perin's first two chapters is right, then not only does Sextus not eschew the "demands of reason," in fact he recognizes them as necessary and respects them. What is more, his practice turns out to be a unique means of satisfying those demands.

In his third chapter, Perin turns to the vexed issue of the scope of Pyrrhonism, defending a...