Not only does Kant take over Descartes’s position on the cogito sum with its influence on the meaning of the a priori, but he likewise takes over, as beyond question, the ontological conception of being as the esse of esse creatum: as mere being-present, mere happening-to-be. (Right now I can’t show in detail that Descartes in fact understood the sum in his cogito sum in this way. [332] I demonstrated that in some earlier lectures by way of a thoroughgoing interpretation of the Meditations.)94
In the final analysis Kant interprets these structures of the I and the “I think” in terms of the co-presence of something-present and an “I.” However, he likewise interprets the I as something that has . . . , as that for which some thing is present. He interprets the I as the constantly self-identical, to whose very presence thinking qua “I think” can come back at every moment in which a being-present-with is possible. To put it briefly: Kant tries to interpret the “I think something”—or in general, the “I have something given”—with ontological determinations that pertain to the “something” that can be given but that do not pertain to the “I think” and the being of the “I.” He thinks he can understand the “logical personality” within the formal structures taken from a form of being that in Kant’s sense is simply the ontological opposite of the “I.” He determines the I—which in fact he sees and understands as the most original and the absolutely unique—by means of empty, formal ontological determinations.
The original synthesis is characterized by the fact that (1) it is itself the I’s act of relating-to-something, and this relating-to is always an “I have”; and likewise that (2) by its nature it is the pre-viewing of unity, an act that is a priori constitutive of the I qua combining. This I—or as Kant constantly says, the pure apperception—is this original synthesis; or the [pre-viewed] “unity” is a synthetic unity of the pure apperception.
The original synthesis, which we have interpreted as the phenomenon of self-apprehension, is the most original in yet another sense: because it is the basis of every concrete act of combining, each of which, for its part, requires its own specific pre-viewing or presenting of a unity. These unities that pertain to the various possible actions of the understanding as unifications are what we must discover if we are to show, in the basic statements, what is a priori known in the knowledge of nature (i.e., what is thought beforehand in the principles). These unities are the pre-viewed bases-on-which [333] of every act of judgment. Kant finds them (or believes he finds them) by establishing the possible
94. [Einführung in die phänomenologische Forschung, Heidegger’s first lecturecourse at Marburg, Winter Semester 1923–1924, was published under that title as GA 17, ed. Friedrich-Wilhelm von Herrmann (Frankfurt am Main: Vittorio Klostermann, 1994; 2d edition, 2006); published in English as Martin Heidegger, Introduction to Phenomenological Research, trans. Daniel O. Dahlstrom (Bloomington: Indiana University Press, 2005).]