Thousands of Nazi youth were whipped into a frenzy in Berlin by Nazi Gauleiter Joseph Goebbels and burned about 20,000 books by authors thought to be inimical to the Third Reich – authors like Erich Maria Remarque, Heinrich Heine, Karl Marx and others. A very simple memorial of that atrocity can now be found in the center of the square, consisting of a glass panel allowing a view below the surface into a white room with empty book shelves large enough to hold the 20,000 volumes destroyed in the mid-30’s. There is also a plaque which contains these prophetic lines by Heinrich Heine: “Those who start by burning books end up burning people.”

The powerful memorial shows the ugly and ominous meaning of an historical inflexion point. Looking for a similar window into that era and its actors, scholars in recent decades have also been excavating beneath the surface career of Heidegger, trying to find answers to such vexing questions as why a philosopher of his talents and stature would fall for such political barbarism. Looking for warning signs about how totalitarian threats develop, they have been asking whether his pro-Nazi political commitments vitiate the whole of Heidegger’s work or simply show up a weakness in one corner of it – namely, his failure to develop a robust ethics that would preclude that kind of politics. Now a new book offers the most comprehensive of such efforts yet. Written by a French philosopher, Emmanuel Faye, it is titled Heidegger: The Introduction of Nazism into Philosophy. Not yet in English, it sheds deep insight into the record because Faye had access to great new troves of information about Heidegger, including his lectures, teaching notes, letters, student notes and other personal documents.

Faye’s fine book is a cautionary tale about a giant of 20th-century philosophy, who now stands revealed as having feet of clay. Heidegger first drew attention across the Continent with his magisterial book, Being and Time, published in 1927. Heidegger’s express purpose in that work was to offer a fresh and powerful treatment of what he called ‘”fundamental ontology.” “Ontology” can be defined simply, if glibly, as the effort to answer the question “What is there and how does it hang together?” Pursuing this question, Heidegger wanted to dig deeper, to try to understand what makes possible any and all of what there is.

Heidegger’s approach was to make a central and decisive distinction between being (Sein) and beings (Seienden). He criticized the history of Western philosophy for concentrating on beings and forgetting being. We are all familiar with “beings” – tables, chairs, ice trays, wisdom teeth, etc. But what we forget, according to Heidegger, is to attend to what makes these things – these beings – possible: Being itself. To be sure, other philosophers have considered the question of being: Aristotle anatomized different senses of the ways that we speak of being and how they relate to each other; Hegel talks about being as the most general category and therefore the emptiest – so empty as to be close to indistinguishable from nothing.

But Heidegger wants to surface a more vibrant, resonant, and suggestive notion of being. In fact, it’s fair to say that Heidegger mobilizes the notion of being as a sort of hook to draw forth from us a sense of astonishment and wonder that can be evoked by the question that Heidegger, (and a few other philosophers like Leibniz and Schelling) pose: “Why is there anything rather than nothing?”

That was just the starting point from which Heidegger developed a series of powerfully suggestive insights. As a result his influence began to spread not only across geographical borders but also across the borders separating intellectual disciplines, making a significant impact on art, literature, theology, and political theory, to name only a few. In fact, the list of thinkers and intellectual movements that were influenced by Heidegger reads like a “Who’s Who” of Western, especially European, thinkers throughout the last century.

Heidegger’s attempt to retrieve a more robust sense of being proceeded through a close analysis of human experience in daily life, not as a sort of philosophical anthropology or psychology, but as a “privileged” area of investigation which allows insight into being itself. Heidegger focuses on the sense of human being as “thrown” into a lived world with others, bounded by time, forced to make choices in anxiety. These, for Heidegger, are more primordial illuminations of our being – and being itself – than the categories of cause, substance and so on that Kant thought structure and make possible human experience.

In that sense, Heidegger can be said to give a more philosophically systematic foundation to the unsystematic writings of Soren Kierkegaard, and it is for that reason that Heidegger has been called the founder of existentialism. Certainly that’s how Jean-Paul Sartre saw things, and his book Being and Nothingness features Heideggerean themes all the way through, although Heidegger later maintained that Sartre had not understood him correctly and rejected the “existentialist” label.

Heidegger’s influence extended far beyond French existentialism, and included the “deconstructionism” of Jacques Derrida and thinkers of the Frankfurt School, including the left-leaning popular philosopher Herbert Marcuse. At the other end of the political spectrum Leo Strauss – lately hailed as the father of American “neoconservatism” – also acknowledges an intellectual debt to Heidegger.

Obviously, Heidegger’s influence has spread far and wide. At the same time, there was a spreading, if reluctant, awareness and concern about Heidegger’s involvement with the Nazi party, and gradually the outline has emerged of this episode and its impact on the philosopher.

It has been an evolving story. It was widely known early on that Heidegger joined the Nazi party shortly after becoming the Rector at the University of Freiburg. In his Inaugural Address as rector, delivered May 27, 1933 and called “The Self-Assertion of the German University,” Heidegger included three “Heil Hitlers” and an exhortation to the students “to exploit at its best the fundamental possibilities of the originally German stock and to conduct it to domination.” He also urged students not to let “theories and ‘ideas’ be the rule of your being. The Führer himself and he alone is German reality and law, now and for the future.”

This was public, as was the fact that Heidegger dropped his dedication to his mentor, the Jewish philosopher Edmund Husserl, in editions of Being and Time published during that period.

But much of his involvement has remained buried until more recently. For years, Heidegger claimed that he was simply putting up a front to appease the political powers of the time in order to protect the independence of the university. He also claimed that he resisted such Nazi predations as the book-burnings mentioned above, including one that took place at his own Freiburg University. As a result of his statements, academic opinion about Heidegger split in the mid-20th century and later – between those who took a rather lenient attitude toward his political entanglements and those who held that his political persuasions reflected backward and undercut all of his philosophical speculations.

In that first group were thinkers like Hannah Arendt, a Jewish student of Heidegger who later became his lover: with her impeccable anti-Nazi credentials, she was a weighty voice in discounting Heidegger’s Nazi indulgence simply as an “error.” On the other hand, Karl Lowith and Immanuel Levinas, among other thinkers, argued that Heidegger’s embrace of Nazism was “immoral” and revealed flaws inherent in his philosophy.

Over more recent decades scholars have probed deeper and deeper below the surface of Heidegger’s career, and what they have found has been devastating for the thinker’s reputation. For his 1978 book, Heidegger and Nazism, Victor Farias had access to many documents, in particular some preserved in the archives of the East German domestic intelligence service, Stasi. Since Farias’ book, no one denies Heidegger’s historical involvement with Nazism and support of Hitler’s policies and person.

Faye’s book not only quantitatively surpasses earlier excavations, it is also qualitatively more decisive: his research shows how Heidegger himself explicitly connected his earliest philosophizing to the Nazi cause. For example, as Heidegger’s entanglement with the Third Reich grew, he came to identify his crucial distinction and connection between being and beings as the connection between the Nazi state and the German people and other citizens of the Reich.

Now, one might argue that Heidegger’s deceptive later gloss on his own earlier philosophy does not destroy the validity of those earlier efforts. And unquestionably there will be many thinkers, perhaps especially in France, who still see great promise and value in Heidegger.

But the accumulation of deeply troubling quotations from Heidegger – now visible below the smooth surface of his defensive statements over the years – casts an ugly pall over all his work. Consider, for example, this statement in which Heidegger bemoans the ways that modern technology has taken over agriculture: “Agriculture is now a motorized food-industry – in essence, the same as the manufacturing of corpses in gas chambers and extermination camps.” Like the window in the Bebelsquare in Berlin showing empty book shelves, statements like this reveal a disturbing emptiness, a hollowness, at the center of his basic approach.

Robert Steck is an occasional lecturer in philosophy and rhetoric and a communications consultant.