Defeat as Philosophical Victory

In this fifth lecture, Richard Polt walks through the final stretch of Plato's Theaetetus, where Socrates and his interlocutors try every available strategy to pin down what knowledge really is. Starting from the problem of false judgment, the discussion moves through the aviary model of memory, the dream theory of perceivable but unknowable elements, and three versions of what it means to give an "account" of something: putting judgment into words, listing elements, and identifying a distinguishing mark. Each attempt collapses under scrutiny. The lecture highlights how spelling a name correctly could be a lucky guess, anticipating the modern Gettier problem that undermines justified true belief. Polt also connects these ancient puzzles to Descartes's self-evident truths, the unity of music and memory, and even questions about AI and learning. The dialogue ends without a definition of knowledge, but Socrates insists this apparent defeat is itself a philosophical victory.