The conceptuality meant in the basic concepts is a concretely giving basic experience, not a theoretical grasping of the matter. That which is so experienced is addressed to something. What is thus experienced and posited in this regard becomes explicit and becomes vital in the address. What is the concretely giving basic experience, and in what regard is it addressed? We must recover the indigenous character as it became vital in Greek science. In the definition, the concept becomes explicit; it comes to light. Definition: proximate genus and specific difference. We want to understand what definition means by questioning back to what it meant for the Greeks, for Aristotle  . Ὁρισμóς [horismos]: “circumscription,” “delimitation.” Ὁρισμóς: λóγος ουσίας [logos ousias]. What is meant by λóγος, by οὐσία, by λóγος ουσίας? By clarifying that, we will find the indigenous character of the concept.

In traditional scholastic language, concepts are (1) notio, (2) intentio, (3) conceptus, (4) species. [HEIDEGGER  , GA18:18-19]