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Protagoras (c.490–c.420 BC)

DOI: 10.4324/9780415249126-A098-1
Version: v1,  Published online: 1998
Retrieved August 14, 2020, from

Article Summary

Protagoras was the first and most eminent of the Greek Sophists. Active in Athens, he pioneered the role of professional educator, training ambitious young men for a public career and popularizing the new rationalist worldview that was introduced from Ionian natural philosophy. But unlike his contemporary Anaxagoras, Protagoras was sceptical of the dogmatic claims of the new science. His famous formula – ‘Man is the measure of all things, of things that are, that they are, and of things that are not, that they are not’ (fr. 1) – makes him the father of relativism and even, on some interpretations, of subjectivism. He was also considered the first theological agnostic: ‘Concerning the gods, I am unable to know either that they exist or that they do not exist or what form they have’ (fr.4). He was sometimes associated with the claim ‘to make the weaker argument (logos) the stronger’.

Citing this article:
Kahn, Charles H.. Protagoras (c.490–c.420 BC), 1998, doi:10.4324/9780415249126-A098-1. Routledge Encyclopedia of Philosophy, Taylor and Francis,
Copyright © 1998-2020 Routledge.

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