Tom Sheehan on the undisclosed clearing.
As William J. Richardson pointed out over fifty years ago, Heidegger’s lecture “On the Essence of Truth,” delivered in December of 1930 but not published until 1943, is the “decisive point” in Heidegger’s development and constitutes the “breakthrough” in which “Heidegger I becomes Heidegger II.” That breakthrough consisted in Heidegger’s insight into the intrinsic hiddenness of the appropriated clearing. Being and Time had spoken of the hiddenness of thrown-openness, but not in terms of the clearing as such. The inaugural lecture at Freiburg, “What Is Metaphysics?” (1929), took a small step forward when it spoke, somewhat hesitantly, of “the essential impossibility of determining” the clearing, the no-thing encountered in dread. However, it was not until a year later, in “On the Essence of Truth,” that Heidegger began to articulate his dawning insight that the clearing is hidden in and of itself and not because of the limitations of our knowing powers. The lecture reaches its climax in section 6, where Heidegger declares for the first time in his career that, in contrast to ἀλήϑεια-2 as the disclosedness of things, ἀλήϑεια-1, as the openness of the clearing, is un-disclosed, and this un-disclosedness is the very essence of the clearing.