koinon, as that from which every being in its being thus-and-so receives the common What.
Because the being is interrogated as such, it is also experienced with respect to the simple fact that it is. Therefore, a further question at once arises from the question of what the being as such is: Among all beings as beings, which one most nearly corresponds to what is defined as the What of the being? The being that corresponds to whatness, the essentia of beings as such, is what truly exists. In the question "What is the being?" the truly existing is thought at the same time with respect to essentia and existentia. In that way, the being is determined as such; that is, determined as to what it is and as to the fact that it is. Essentia and existentia of the ens qua ens answer the question "What is the being as such?" They define the being in its Being.
Accordingly, how does metaphysics comport itself to Being itself? Does metaphysics think Being itself? No, it never does. It thinks the being with a view to Being. Being is first and last what answers the question in which the being is always what is interrogated . What is interrogated is not Being as such. Hence, Being itself remains unthought in metaphysics, not just incidentally, but in accord with metaphysics' own inquiry. By thinking the being as such, the question and the answer necessarily think on the basis of Being; but they do not think about Being itself, precisely because in the most proper sense of the metaphysical question Being is thought as the being in its Being. Inasmuch as metaphysics thinks the being on the basis of Being, it does not think Being as Being.
To think on the basis of Being docs not yet mean going back to Being, thoughtfully recalling it in its truth. Being remains unthought in the kind of thinking that, as metaphysical , passes for thinking pure and simple. That Being itself remains unthought in metaphysics as such is a remaining-unthought of a peculiar, distinctive, and unique kind.
The metaphysical question does not extend to Being itself. How could we expect it to ponder Being itself? However, dare we say that the question of metaphysics does not go far enough in its questioning, that it does not go far enough beyond beings? We leave that question open, simply because we have not yet decided whether or not metaphysics