Black forest philosopher Martin Heidegger Thinking an Unthinkable. Heidegger's Black Notebooks: A Panel Discussion with Peter Trawny and Babette Babich br On April 8th, 2014 at the Goethe Institute in New York City, Roger Berkowitz, Academic Director of the Hannah Arendt Center at Bard College, discussed Martin Heidegger's "Black Notebooks" with Peter Trawny, director of the Martin Heidegger Institute at the University of Wuppertal. Trawny has just edited three volumes of Heidegger’s Black Notebooks, philosophical notebooks Heidegger kept from 1931-1941. In these notebooks Heidegger works out his ideas of what he calls a “spiritual National Socialism” & Heidegger in Black by Peter E.