Do not think that one has to be sad in order to be militant, even though the thing one is fighting is abominable.

At the ENS Foucault's classmates unanimously summed him up as a figure who was both "disconcerting and strange" and "a passionate worker". In 1954 Foucault authored an introduction to Binswager's paper "Dream and Existence" in which he argued that dreams constituted "the birth of the world" or "the heart laid bare" expressing the mind's deepest desires. He would praise sado-masochistic activity in interviews with the gay press describing it as "the real creation of new possibilities of pleasure which people had no idea about previously.

Foucault is best known for his critical studies of social institutions most notably psychiatry social anthropology of medicine the human sciences the prison system and the history of human sexuality. Foucault died in Paris of neurological problems compounded by HIV/AIDS; he was the first public figure in France to have died from the disease with his partner Daniel Defert founding the AIDES charity in his memory. From 1966 to 1968 he lectured at the University of Tunis Tunisia before returning to France where he involved himself in several protest movements and left-wing groups.