When Emmanuel Faye’s book “Heidegger – L’introduction du nazisme dans la philosophie” was published in France in March 2005, it immediately caused a huge stir. Heidegger research had to feel caught out for a moment, because the Descartes specialist Faye cleverly knew how to attract attention with unpublished material and a hard-hitting thesis. Worldwide. He wanted Heidegger to prove nothing less than the “introduction of National Socialism into philosophy”. To do this, Faye evaluated previously unknown seminar notes from the winter semesters of 1933/34 and 1934/35 that were made available to him. They were what was actually new in the book and the starting point for an unmasking story that had never been told before.