in such a way that we are directed toward the terminological by way of the customary.
The customary meaning of οὐσία designates a definite being, and not, say, mountains or other humans. Οὐσία is, terminologically, “a being in the how of its being.” (Usually translated as “substance,” it remains undecided whether more can be represented by “substance” than by “a being in the how of its being.”) In the customary meaning, this “in the how of its being” is not emphasized. But the German expressions also have certain meanings that do not only intend a being, but also intend that being in the how of its being: estate, property, goods and chattels. Οὐσία is a being that is there for me in an emphatic way, in such a way that I can use it, that it is at my disposal. It is that being with which I have to do in an everyday way, that is there in my everyday dealings with the world, as well as when I engage in science. It is a privileged, fundamental being considered in its being, in the how of its being, and in the customary meaning the how of being is co-intended. The how of being refers to being there in the manner of being-available. This suggests that from the outset being, for the Greeks, means being there. The further clarification of beings in their being has to move in the direction of the question: what does there mean? The being of beings will become visible through the clarification of the there-character of beings.
We can now see how the terminological meaning of οὐσία is derived from the customary. Οὐσία customarily is a definite being in the how of its being; the how is only co-intended. The terminological meaning, on the other hand, thematically yields the how of being that was previously only intended implicitly. And this holds not only for the how of this way of being, but for every being. Οὐσία can mean (1) the being directly (the how is co-intended) and (2) the how of a being directly (this being itself is co-intended). Therefore, οὐσία means (1) a being and (2) the how of being, being, beingness, being in the sense of being-there. Οὐσία in the sense of being-there contains a double meaning: (1) the being that is there and (2) the being of the being that is there.
It is no accident that the Greek designation for the things that they first encounter is πράγματα, “beings with which one constantly has to do,” and χρήματα, “what is taken into use.” They refer to the basic meaning of οὐσία.
Aristotle says in the Metaphysics that the old question: τί τὸ ὄν, “what is the being?” is really the question concerning the being of beings: τίς ἡ οὐσία.22 Aristotle brings scientific research, for the first time, to this ground, a ground that even Plato never noticed.23
c) The Terminological Meaning of Οὐσία
Οὐσία is the title of the object of genuine fundamental research for Aristotle
22. Met. Ζ 1, 1028 b 2 sqq.
23. See Hs. p. 345 f.