The Soul Behind the Senses

In this fourth session on Plato's Theaetetus, Richard Polt traces Socrates' final arguments against the idea that knowledge is simply perception. The lecture examines how the psyche unifies consciousness across the separate senses, and why concepts like being, sameness, and goodness cannot be delivered by perception alone. These common concepts require reasoning that unfolds over time through education and effort. With perception defeated, the dialogue turns to a new proposal: knowledge as true judgment. But this raises an immediate puzzle. How is false judgment even possible? Polt walks through three arguments that seem to rule out false belief entirely, then introduces the wax block model of memory as Plato's attempt to rescue the possibility of error. The model works in some cases but ultimately breaks down, setting the stage for the dialogue's final move: the proposal that knowledge is true judgment plus an account, and the deep difficulty of defining what counts as a genuine account.