Clifford Roberts

The aim of this paper is to explain why Thrasymachus, upon first appearing in Republic I, prohibits Socrates from defining justice as what is good. I argue that Thrasymachus views such definitions as equivocal, since he conceives of the good as relative: what is good must be good for someone. This relative conception of the good makes Thrasymachus similar to the sight-lovers, who believe in good things, which are relatively good, but deny the existence of the good itself, which is absolutely good. Understanding Thrasymachus as a sight-lover permits an illuminating reframing of his outlook and his significance for the larger project of the Republic.

This dissertation focuses on the philosophy of Sextus Empiricus, a skeptic who provides the most complete account of Pyrrhonian skepticism that survives from antiquity. In particular, this dissertation examines Sextus' account of skeptical assent, the attitude that structures and informs the life of the skeptic. Accordingly, this dissertation has two aims: first, to elaborate and defend a novel method of interpreting Sextus' claims and concepts, one based on their significance in ordinary life and language; and, second, to apply this method to Sextus' claims about the nature of skeptical assent in order to generate a novel account thereof. In the first chapter, the most widely-held and influential interpretations of skeptical assent are elaborated and taxonomized. It is argued that all these interpretations neglect to pay sufficient attention to the self-reflexivity of Sextus' skepticism, in consequence of which Sextus' own claims about skeptical assent must be understood as expressing skeptical assent. It is argued, moreover, that this neglect of self-reflexivity cannot be remedied without abandoning these interpretations. In the second chapter, Sextus' claims about ordinary life are examined and it is argued that Sextus regards skepticism as a distinctive expression of ordinary life. However, ordinary life may be understood in two different ways and the failure to distinguish them has resulted in a misconception of Sextus' outlook. The two different conceptions are therefore elaborated and it is argued that Sextus' understanding of ordinary life accords with only one of them. Finally, responses are provided to some important objections to the close connection between iii skepticism and ordinary life. In the third and final chapter, Sextus' conception of ordinary life is deployed to produce a novel understanding of skeptical assent. The focus here is Sextus' account of assent in Outlines of Pyrrhonism 1.13. Each of the key concepts in that account are explained in light of chapter two's results. Additionally, the roots of a concept central to skeptical assent are located in Aristotle's methodological reflections. Finally, the novel account of skeptical assent is distinguished from two other closely related accounts.. iv.