The model of the double séance works above all for Derrida's central concept of différance, a term that, as much as “deconstruction,” has come to represent his philosophy. Derrida introduced différance to the French intellectual public in his 1966 paper “Freud and the Scene of Writing.” But if this paper marked in a sense an origin, it was not a simple one. Already, in the opening pages of the text, Derrida gave a waypoint for a history of the term, referring to a passage in his recently published article “Of Grammatology.” But, significantly, the word différance did not appear in the passage cited, nor indeed in the whole of that article. The passage read:

Drawing out those parts in Heidegger's text where he complicated any understanding of the “truth of Being” as a “transcendental signified” and suggesting that it too was a sign, Derrida argued that the ontico-ontological difference could no longer be primary; the difference between Being and beings appealed to a Being that was itself riven with difference. Because Being and its ontic determinations were both signs, the (structuralist) difference at the heart of signification preceded that between Being and beings.

If the passage asserted a rupture, it was contained within the word “difference,” between the “ontico-ontological difference” and “difference tout court” – repetition without identity – which came into tension with itself over the course of the footnote. The tension was only formally recognized later, in the book form of De la grammatologie, which grew out of the two original articles, when this more “originary” difference was rewritten as “différance.” No longer the temporalization and differing of the ontico-ontological difference, the deferral of Being that could only show itself in hiding itself, Derrida's différance, spacing and temporalization, preceded and constituted Heidegger's.