156n.) Heidegger distinguishes three levels or modes of assertions according to which a theoretical assertion about something present-at-hand constitutes an "extreme." (10) Subsequently, Heidegger attempts to articulate a clearing (Lichtung) that is neither present nor absent, and comes into its own (ereignet sich) in a way irreducible to the presence/absence and manifestness/hiddenness interplays; see, for example, Martin Heidegger, "Was hei[beta]t denken?" and Martin Heidegger, "Aletheia (Heraklit
, Fragment 16)," in Vortrage und Aufsatze (Pfullingen: Neske, 1954), 128-9, 136-7, 264, 268; Martin Heidegger, Zur Sache des Denkens (Tubingen: Niemeyer, 1976), 20-5, 72-4; Martin Heidegger, Was hei[beta]t Denken?
We should also reread, from this perspective, the 1943--44 course on Heraclitus (1979a, 127 ff.) on the interpretation of philia in the name philosophy (philia tou sophou) or of philein in the Heraclitean saying ("Der Spruch Heraklits
: phusis kruptesthai philei").