Plato on the rationality of belief. Theaetetus 184-7

Abstract

This paper offers an explanation of why Plato, in his later dialogues, begins to view the capacity of belief formation as necessarily involving the reasoning part of the soul. I will argue that the standard explanation, according to which for later Plato forming beliefs requires cognitive access to intelligibles (Forms), is unsatisfactory. My focus will be on the passage from Plato's Theaetetus (184B-187A), which is crucial for understanding Plato's notion of belief. I will argue that this passage does not support the standard explanation, and develop an alternative reading of the passage, according to which forming a belief is a goal-directed activity aiming at truth. In other words, it is the epistemic goal of forming beliefs that matters for Plato, not the cognitive preconditions.