The year 1929 saw, besides the publication of KM and WG, Heidegger's accession to the chair of philosophy at the University of Freiburg, left vacant by Husserl's retirement, a new distinction that furnished the occasion on July 24 for the inaugural lecture, "What is Metaphysics?" (WM).¹ Here Heidegger crystallizes once more the essential elements of the thought so carefully elaborated in SZ, with the result that in a genuine sense we may say that WM offers no doctrine of importance that is new. And yet there is a profound difference of perspective from that of SZ, which must be noted and emphatically stressed, if we are to discern the evolution that already has begun.