During the 1950s, in one of his most obstinately creative periods, Marcuse confronted the theoretical challenges posed by the pessimism of works like Sarte's Being and Nothingness and Adorno's and Horkheimer's Dialectic of Enlightenment. The series of defeats of the Left suffered by Marcuse since the failure of the German Revolution of 1918, the intensification of the cold war and arms race, the emergence of a form of consumer capitalism which he despised, the anti-Communist witchhunts of the McCarthy era, and his own difficult personal circumstances made Marcuse vulnerable to the pessimistic philosophical doctrines that were in the air. He did not surrender to despair, however, but set out instead to work on developing his own critical theory of contemporary society and vision of liberation through an intensive study of Freud, classical and modern literature, philosophy and aesthetics.