Plato on Episteme and Propositional Knowledge

Epistêmê cannot just be a matter of knowing a logos. Knowledge, it appears, is demonstrated not in the knowledge of any particular logos, but in the ability to defend a logos against refutation. It is precisely the latter ability that is characteristic of epistêmê. This ability, furthermore, cannot be imparted by means of a logos. For, no logos suffices to endow its possessor with the ability to defend it (i.e., the logos) against refutation. Given that Plato appears to have believed that no knowledge of a logos—no matter how elaborate the logos—is sufficient for epistêmê, one can see why he was drawn to describing epistêmê as requiring a direct intuition of Forms. One can also see why he was inclined, in describing such direct intuition, to use the language of visual perception. When I see an object, I can describe the object—or answer questions about it posed to me by someone who does not see the object—but no logos that I can give exhausts the content of what I see. It is true that some contemporary philosophers would take issue with the claim that the content of visual perception is non-propositional. However, it is not implausible to suppose that Plato thought of the content of visual perception in this way