Richard Wolin at the LARB:
The controversies that have haunted the publication of Heidegger’s work are significant, insofar as they concern not merely occasional and understandable editorial lapses but instead suggest a premeditated policy of substantive editorial cleansing: a strategy whose goal was to systematically and deliberately excise Heidegger’s pro-Nazi sentiments and convictions. As Heidegger scholar Otto Pöggeler observed appositely, “Heidegger is like a fox who sweeps away his traces with his tail.”
The problems began with the postwar publication of Heidegger’s lecture courses from the 1930s, as Germany and Europe struggled to climb out from under the ruins of the “German catastrophe.” In Introduction to Metaphysics (1953), Heidegger had falsified his disturbing paean to the “inner truth and greatness of National Socialism,” adding a parenthetical clarification that referenced “the encounter between planetary technology and modern man.” When queried about the authenticity of the passage in question, Heidegger doubled down on his initial duplicity, falsely claiming that the parenthetical remarks had been in the original manuscript but that he had omitted them when the course was first presented in 1935. When, at a later point, scholars sought to establish the veracity of Heidegger’s claim by consulting the original manuscript, they were taken aback to find that the page in question had inexplicably gone missing.
more here.