endeavors were to bring to light this intrinsically hidden “whence” that classical ontology had overlooked and forgotten. Being (Sein) in all its incarnations is the topic of metaphysics. Heidegger, on the other hand, is after the essence or source of being and thus the ground of metaphysics.

In the second place, long before Being and Time, Heidegger had carried out a Copernican Revolution under the banner of phenomenology. He took a decisive step away from the naïve realism of the Aristotelian-Thomistic ontology in which he had been steeped as a young man, in order to focus instead on the correlativity of man and being in what he would eventually call a “phenomenological ontology.”⁷⁷ This means that the only entrance into Heidegger’s work is through the phenomenological reduction. Over the door of his Academy is engraved ἀϕαινομενολέγητος μηδεὶς εἰσίτω, which translates roughly as follows: “No phenomenological reduction? Don’t even try to get in.”⁷⁸

The material object of traditional metaphysics is the real insofar as it lies ἔξω ὂν καὶ χωριστόν: “outside of thinking and separated from it [= independent of it].”⁷⁹ Phenomenology, on the other hand, regards things only insofar as they are meaningfully present to us within our concerns and performances—that is, insofar as they are “present to mind” in the broadest sense.⁸⁰ Years ago Professor Aron Gurwitsch pointed out that once one has carried out the phenomenological reduction (the sine qua non of phenomenological work) “there are no other philosophical problems except those of sense, meaning, and signification.”⁸¹ To the degree that Heidegger’s work is phenomenological (and to the end of his life he insisted it was),⁸² it was solely and exclusively about meaningfulness and its source. Heidegger interprets the essence of “mind” in terms

77. SZ 38.21 = 62.32, my emphasis.
78. On the legendary inscription over the entrance to Plato’s Academy (“No one who is ignorant of geometry may enter”), see Henri-Dominique Saffrey, “Ἀγεωμέτρητος μηδεὶς εἰσίτω.” See also Johannes Philoponus, In Aristotelis de anima in Commentaria in Aristotelem Graeca, XV, 117.16–17.
79. Metaphysics XI 8, 1065a24. See ibid., ἔξω [τὴς διανοίας]: Metaphysics, VI 4, 1028a 2, taken with 1027b34–1028a1: “outside” [i.e., independent] of thinking. See GA 6, 2: 380.2–13 = 16.17–26.
80. GA 83: 80.8: “Anwesung für das Verstehen.” See Aquinas, Scriptum super sententiis, I, distinctio 3, quaestio 4, articulum 5, corpus: “id quod est praesens intelligibile.”
81. Gurwitsch, 652.8–9 (italicized in the original).
82. See GA 14: 147.15–16 = 201.1: “die weitere Frage [re das Wesen des Seins], die ich als phänomenologische beanspruche.” Ibid. 54.2–3 = 44.32–33: “Dieses Vorgehen [in ‘Zeit und Sein’] kann als phänomenologisch bezeichnet werden.”