scientific knowledge is everywhere based on something useless. The claim of the identity of the object speaks, whether the sciences hear it or not, whether they throw to the winds what they have heard or let themselves be strongly affected by it.
The claim of identity speaks from the Being of beings. However, where the Being of beings appears, most early and most authentically in western thought — with Parmenides — there speaks τὸ aὐτὸ, that which is identical, in a way that is almost too powerful. One of Parmenides’ fragments reads: τὸ γἀρ aὐτὸ νοεῖν ἐστίν τε καὶ εἶναι.
“For the same perceiving (thinking) as well as being.”
Different things, thinking and Being, are here thought of as the Same. What does this say? It says something wholly different from what we know otherwise as the doctrine of metaphysics, which states that identity belongs to Being. Parmenides says: Being belongs to an identity. What does identity mean here? What does the word τὸ aὐτὸ, the Same, say in Parmenides' fragment? Parmenides gives us no answer. He places us before an enigma which we may not sidestep. We must acknowledge the fact that in the earliest period of thinking, long before thinking had arrived at a principle of identity, identity itself speaks out in a pronouncement which rules as follows: thinking and Being belong together in the Same and by virtue of this Same.
Unintentionally we have here already interpreted τὸ aὐτὸ,