The first part of my commentary on Martin Heidegger’s account of Plato’s Theaetetus, in The Essence of Truth, led from Socrates’ statement of the dialogue’s main question: “what is knowledge?” up to the rejection of Theaetetus’ first answer: knowledge is perception.
It was shown that perception, that which is given through the senses does not give us access to beings, and therefore cannot have a relation to knowledge, understood as the possession of truth, and therefore to being.
Rather than through the senses, knowledge is to be found in the soul’s striving relationship to beings, which gives us the possibility of their unhiddenness as being. The question then becomes about the character of this relationship, in which the possession of truth and therefore knowledge is made possible. It is immediately seen that this relationship has what Heidegger calls a double claim, it is in the relationship to beings, but it is also that which gives beings in their presence, such that they show themselves from themselves – i.e. as appearance.
The task then becomes the discovery of the phenomenon that involves this duality, the self-showing of beings as well as the soul’s relationship to being. This leads to Theatetus’ second answer to Socrates’ question, that “knowledge resides in the region of doxa,” the question now is what does doxa mean?