Theaetetus

by Plato

"Theaetetus" by Plato is a philosophical dialogue written in the early-middle 4th century BCE. In this foundational work of epistemology, Socrates questions the young mathematician Theaetetus about the nature of knowledge itself. They examine three definitions—knowledge as perception, as true judgment, and as true judgment with an account—but each proves unsatisfactory. The dialogue ends without resolution as Socrates departs to face trial for impiety, leaving the essential question unanswered.