Protagoras

Protagoras (prōtăg`ərəs), c.490–c.421 B.C., Greek philosopher of Abdera, one of the more distinguished Sophists. He taught for a time in Athens, where he was a friend of Pericles and knew Socrates, but was forced to flee because of his professed agnosticism. Protagoras was the author of the famous saying, "Man is the measure of all things." He held that each man is the standard of what is true to himself, that all truth is relative to the individual who holds it and can have no validity beyond him. Thus he denied the possibility of objective knowledge and refused to differentiate between sense and reason. None of his works have survived, but one of Plato's most famous dialogues bears his name.

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Protagoras

(born 485, Abdera, Greece—died c. 410 BC) Greek philosopher, first and most famous of the sophists. He spent most of his life at Athens, where he considerably influenced contemporary thought on moral and political questions. Plato named one of his dialogues after him. Protagoras claimed to teach men “virtue” in the conduct of their daily lives. He is best known for his dictum, “Man is the measure of all things” (see relativism; ethical relativism). Though he adopted conventional moral ideas, his work Concerning the Gods advocated agnosticism regarding religious belief. He was accused of impiety, his books were publicly burned, and he was exiled from Athens c. 415 BC.

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Protagoras

?485--?411 bc, Greek philosopher and sophist, famous for his dictum "Man is the measure of all things."