“… ‘Sinn von Sein’ und ‘Wahrheit des Seins’ sagen das Selbe.” (GA9, Was ist Metaphysik?, p. 18). See: GA9, CartaH, p. 84; GA9, Was ist Metaphysik?, p. 44; Holzwege (GA9), 2nd ed. (Frankfurt: Klostermann, 1952), p. 245. Cf. Sein und Zeit, 6th ed. (Tübingen: Niemeyer, 1949), p. 151. (RHPT:7)
This proposal to ground metaphysics by interrogating the sense of Being as the process of ἀ-λήθεια through which the ontological difference (ontologische Differenz) breaks out has been Heidegger’s unique preoccupation since the first pages of Being and Time (1927). One must admit, of course, that the focus on the difference (Differenz) as difference becomes sharper in the later years than we find it in the beginning, and the evolution in clarity will warrant very special attention. But the fundamental position is made sufficiently clear as early as the inaugural address of 1929, when the author formulates the ground-question with Leibniz’ formula: “why are there beings at all and not much rather Non-being?” (Warum ist überhaupt Seiendes und nicht vielmehr Nichts?” (GA9, Was ist Metaphysik?, p. 42)) For Leibniz, of course, the formula asks effectively about a Supreme Being that “grounds” all other beings, is therefore eminently a metaphysical question. For Heidegger, the question means: how is it possible that beings (independently of “where” they might have come from, “who” or “what” may have “caused” them, as metaphysics (Metaphysik) understands these terms) can be (manifest) as beings. In other words, it is a question about the coming-to-pass of the lighting-process of ἀ-λήθεια, which we now understand as the emergence of the ontological difference. What is more, it is a question about this process as permeated by negativity. Heidegger himself expands the question thus: “… How does it come about that everywhere (about us) beings have the primacy … while that which is not a being, which is thought of as Non-being in the sense of Being itself, remains forgotten? …” (Woher kommt es, dass überall Seiendes den Vorrang hat und jegliches ‘ist’ für sich beansprucht, während das, was nicht ein Seiendes ist, das so verstandene Nichts als das Sein selbst, vergessen bleibt?..(GA9, Was ist Metaphysik?, p. 23)) The ground-question meditates not only Being (Sein) but obliviousness to Being (Seinsverlassenheit), the forgottenness (Vergessenheit) of the ontological difference. (RHPT:14)