"Theaetetus" by Plato is a philosophical dialogue written in the early-middle 4th century BCE. Socrates engages the young mathematician Theaetetus in a probing investigation of knowledge itself. Together, they examine three different definitions of what knowledge might be—each seemingly plausible, yet each ultimately unsatisfactory. The dialogue concludes without resolution as Socrates departs to face trial for impiety, leaving the fundamental question unanswered in characteristic Platonic fashion. (This is an automatically generated summary.)