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From Proto-Sceptic to Sceptic in Sextus’ Outlines of Pyrrhonism

  • Robb Dunphy ORCID logo EMAIL logo
From the journal Apeiron


This is an account of Sceptical investigation as it is presented by Sextus Empiricus. I focus attention on the motivation behind the Sceptic’s investigation, the goal of that investigation, and on the development Sextus describes from proto-Sceptical to Sceptical investigator. I suggest that recent accounts of the Sceptic’s investigative practice do not make sufficient sense of the fact that the Sceptic finds a relief from disturbance by way of suspending judgement, nor of the apparent continuity between proto-Sceptical and Sceptical investigation. I offer an alternative account which turns on the suggestion that the Sceptic accepts that justification is the norm of belief.

Corresponding author: Robb Dunphy, School of Philosophy, University College Dublin, Dublin, Ireland, E-mail:


This paper was written during a research fellowship at the Maimonides Centre for Advanced Studies at the University of Hamburg. I would like to thank Stephan Schmid, Yoah Meyrev, Josê María Sánchez de León Serrano, Philip Choi, other fellows of the Centre, and Gabriel Martin for the opportunity to discuss elements of its argument and for their feedback. This paper was significantly improved by the comments provided by two anonymous reviewers for Apeiron, to whom I am very grateful.


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Published Online: 2021-04-02
Published in Print: 2022-07-26

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