Heidegger frequently quotes Angelius Sigelius's statement that the "rose is without why?"¹ In The Principle of Reason, Heidegger appeals to this aphorism in order to circumscribe the limits of the principle of sufficient reason. He outlines the transformation whereby that principle no longer defines the subordination of grounded to ground, but instead prefigures the movement of stepping back into the difference between being and beings, into the priority of that difference.² As he suggests, that principle must undergo a two thousand year incubation in order that the evoking of these new relations, the "crossing over" of a metaphysical emphasis by an alternative configuration of sense, can occur.³ This "crossing over" redefines the philosophical landscape so as to shift the precedence from what has occupied thought to what has remained unthought. The fixity of metaphysical terms gives way to "polyvalent words" like Satz, which denotes not only the conventional meaning of "principle" or "statement," but also a richer sense of "movement."⁴ Such transpositions of meanings prompt thought to undergo a "leap." Thus, the "why?" is placed in abeyance as a receding ground from which thought "leaps" in the direction of an Abgrund, an abyss.⁵