Worth repeating from an old post:
Hate speech? That's a term leftists use for speech they don't like. No one in his right mind could see Heidegger's magnum opus, Sein und Zeit (Being and Time), published in 1927, as anything close to hate speech. The claim that it is is beneath refutation. Nor can his lectures and publications after 1933, when Hitler came to power, be dismissed in this way.
Heidegger undoubtedly inspires violent passions: he was a National Socialist, and what is worse, he never admitted he was wrong about his political alignment. But according to Michael Dummett, the great logician Gottlob Frege was an anti-Semite. (Dummett says this in either the preface or the introduction to Frege: The Philosophy of Language. ) Now will you ignore Frege's seminal teachings because of his alleged anti-Semitism? That would be senseless. And let's not forget that the later Jean-Paul Sartre was not just a Commie, but a Stalinist. Should Critique of Dialectical Reason be dismissed as hate speech? Should we deny Sartre the title 'philosopher' and re-classify him as a Commie ideologue? Of course not. And please no double standard. Why is being a Nazi worse than being a Stalinist? Why is murdering people because of their ethnic affiliation worse than murdering people because of their class affiliation?
You have two highly influential philosophers. One aligns himself politically with the mass murderer Hitler, the other with the mass murderer Stalin. That is extremely interesting, and no doubt troubling, but in the end it is truth that we philosophers are after, and in pursuit of it we should leave no stone unturned: we should examine all ideas in order to arrive as closely as we can to the truth. All ideas, no matter what they are, whether they come from a Black Forest ski hut or a Parisian coffee house, or the syphilitic brain of a lonely German philologist. Haul them one and all before the tribunal of Reason and question them in the full light of day. To understand the content of the ideas it may be necessary to examine the men and women behind them. But once a philosopher's propositions have been clearly set forth, the question of their truth or falsity is logically independent of their psychological, or sociological, or other, origin. To think otherwise is to commit the Genetic Fallacy.
Sartre claimed that man has no nature, that "existence precedes essence." He got the idea from Heidegger's Sein und Zeit, p. 42: Das 'Wesen' des Daseins liegt in seiner Existenz. It is an interesting and influential idea. What exactly does it mean? What does it entail? What does it exclude? What considerations can be adduced in support of it? Questions like these are what a real philosopher pursues. He doesn't waste all his time poking into the all-too-human philosopher's dirty laundry in the manner of Faye and Romano. Are people in this Age of Celebrity incapable of focusing on ideas?
And then there is Nietzsche. If the Gesamtausgabe of Heidegger ought to be marked with a skull-and-crossbones, then a fortiori for the Gesammelte Schriften of Nietzsche. There are dangerous ideas in Nietzsche. See my post Nietzsche and National Socialism. Indeed, Nietzsche's ideas are far more dangerous than Heidegger's. Should we burn Nietzsche's books and brand The Antichrist as hate speech? Stupid!
The Nazis burned books and the Roman Catholic Church had an index librorum prohibitorum. Now I don't deny that certain impressionable people need to be protected from certain odious influences. But Heidegger writings are no more 'hate speech' (whatever that is) than Nietzsche's writings are, and they don't belong on any latter-day leftist's index librorum prohibitorum. Are they both philosophers? Of course. Are they on a par with Plato and Kant? Not by a long shot! Are their ideas worth discussing? I should think so: they go wrong in interesting ways. Just like Wittgenstein and many others.
For social and political diary entries from Frege near the end of his life, see here. (HT: Marius Manci) Very interesting.