On August 28, 1947, Herbert Marcuse initiated a brief epistolary exchange with his former teacher Martin Heidegger. Marcuse had met in person with Heidegger earlier in the summer at Heidegger's Black Forest retreat on Todtnauberg. Atop Heidegger's Magic Mountain, Marcuse articulated the thoughts and sentiments of numerous exiles. He demanded that Heidegger explain his utterances and actions during the Third Reich. Heidegger refused to grant Marcuse's wishes, and the latter returned to the United States with unfinished business. Recording his thoughts for his associates and posterity, Marcuse tried one last time to seek an explanation. Heidegger responded with a letter of his own that is chilling and prophetic in its formulation of rationalizations and justifications that would later become common in West Germany. Examined together, this brief exchange of letters presents a vivid case study of the predicaments and perspectives of the exiles, as well as the presumptions and attitudes toward the exiles that were held by many of those who stayed behind. Although Marcuse had been studying the phenomenon of Nazism as both a member of the Frankfurt School and as a research analyst for the Office of Strategic Services, Heidegger represented a concrete encounter with National Socialism—and as a former teacher, Heidegger also presented Marcuse with an opportunity to grapple with his own intellectual history.

While Marcuse was not the only former student to pose such questions to Martin Heidegger, Marcuse's letters are notable because of their directness. Marcuse was not an intimate of Heidegger, nor was he a favorite student—and yet his letters confront and challenge Heidegger in a manner that is extremely personal and sadly a bit unusual among Heidegger's former students. Although Hannah Arendt and Karl Jaspers confided in each other that they feared that Heidegger had not only erred but also perhaps lost his mind (and remained misguided and unrepentant to the end), both actively contributed not only to the postwar rehabilitation of Heidegger but also to the expansion of his intellectual legacy. Marcuse, on the other hand, confronted his mentor and demanded explanations—but Marcuse's motives during his encounter with Heidegger were as complicated and perhaps as calculated as those of Arendt and Jaspers.