Martin Heidegger, teacher and one-time rector of the University of Freiburg in Breisgau, is without question one of the most mysterious and puzzling personalities, as well as one of the most enigmatical philosophical thinkers of our age. A spectator who watches him come from his Black Forest hideout to enter the Freiburg university lecture hall sees him not only garbed in a costume which is itself peculiar, but enveloped in an air of remoteness and even of mystery, which seems to mark him off sharply from the lives and fortunes of ordinary men. And, during the brief period when he ventured to leave the world of speculative thought, to express himself on political matters, the effort can hardly be said to have been crowned with success, since the purport of his remarks was that Adolf Hitler was a man of genius, and a worthy member of the tradition that began with Socrates, and Plato. His later retraction has been accepted by many, but others who watched him at that period have found his words and actions hard to forget or forgive. Nor are the puzzles he presents limited to the field of politics. His philosophy itself is so difficult that those who call themselves his followers are at odds with one another as to just what it means, and his own frequently expressed judgment is that from the start he has been completely misinterpreted. The point on which all seem to agree is that what he is now saying contradicts what he said earlier.