How can we interrogate Sartre's thought, which embraced philosophy, the novel, theater and the century, and tied conceptual adventure to political commitment? How can we dust off Sartre's cliches? In what way are we heirs to the new way of philosophizing that he instigated, to this new way of posing problems? In other words, in what way is Sartre our contemporary? This essay sets out to answer these questions through an original line of inquiry, confronting Sartre's philosophy of the opposition between man and the world with the thoughts of Spinoza, Nietzsche and Deleuze, to envisage the possibility of a politics resolutely turned towards a post-humanist ecology.