realness of the real?” To articulate this “realness of the real,” Heidegger (like most all other philosophers) employs the two most formally indicative words in the lexicon, in his case, “das Sein” for “realness” and “das Seiende” for “the real.” As formally indicative, all such words (and their equivalents in any other language) are only placeholders, stand-in terms, for whatever Aristotle or Heidegger or any other philosopher thinks the realness of the real consists in. For Plato the realness of a thing consisted in its “ideal intelligible appearance” (εἶδος). Aristotle thought the realness of a thing consisted in its possession of or its functioning unto perfection (ἐντελέχεια, ἐνέργεια), whereas Aquinas thought it lay in the thing’s participation, via creation, in the very life of God. In other words, the terms “realness” or Sein or esse or “being” are only formal indications of what philosophers will argue is the content or meaning of the “realness” of things. For Heidegger, as we shall see, das Sein is only a formal indication of what he will argue is the content of that term—namely, the meaningful presence of something in and for human intelligence. Therefore, in what follows I will use the words Sein, Seiendheit, and “realness” as ex aequo formal indications of the specific, not-yet-determined content that Plato, Aristotle, Aquinas, Heidegger—and we ourselves—have yet to argue for.6
The circularity here is obvious. To ask for the realness of whatever-is-real promotes that question to the level of a second one: What is meant by—what constitutes—the “realness” that things are said to “have” to the degree that they are “real”? Two questions converge here: What is a thing insofar as it is real? What is the very realness that such a thing is said to have? These two questions comprise the work of traditional ontology. Asking and answering a third question—“What is the highest instance of the real-in-its-realness?”—is he work of “natural” (i.e., philosophical) theology. Insofar as metaphysics traditionally comprises both ontology (general metaphysics) and natural theology (special metaphysics), Heidegger refers to it as “onto-theology.”
Aristotle opens up the ontological moment of metaphysics when he declares that “there is a certain science that investigates things insofar as they are real at all.”7 But he also hints (and only that) at the second and more important question at the beginning of Book VI of the Metaphysics, when he says in effect that we will not find an adequate answer to the first question, focused on real things, until we first answer the second question: What do we mean by “realness as such”?8
6. “Realness”: an entity’s existence in what one takes to be “the nature of things”; see
GA 84, 1: 396.9–10
and Suarez, Disputationes metaphysicae, XXXI, section I, 2:
“esse aliquid in rerum natura” and “aliquid reale.”
7. Metaphysics IV 1,
1003a21:
a science of τὸ ὂν ᾗ ὄν. Also ibid., VI 1,
1026a31–32.
8. See SZ 11.18–19
= 31.25–26:
Answering the second question would explain the a priori conditions not only of the ontic sciences but of ontology as such.