In Nausea, the 1938 novel that made Sartre famous, the protagonist is a historian who abandons the biography he is writing because he comes to believe that all histories are fictional, escapist, and useless. He sought the one and only truth of history; a truth that would revolutionize the world. By the time Sartre published his most mature works, he claimed to have written a biography that was perfectly true. This book examines how and why Sartre’s position on the possibility and worth of historical knowledge changed so dramatically. In addition, it illuminates Sartre’s unique contribution to the grand debate between Marxist and anarchist revolutionaries―a debate that continues today.