Jean-Paul Sartre (1905–1980) was a French existentialist; a Marxist philosopher, dramatist, and novelist; and a major political figure on the French Left during the 1950s and 1960s. His chief works of relevance for social theory include L'ego et la Transcendance (The Ego and Transcendence, 1937), l'Être et le Néant (Being and Nothingness, 1943), “l'Existentialisme est un humanisme” (“Existentialism and Humanism,” 1946), and Critique de la Raison Dialectique (Critique of Dialectical Reason—Vol. 1, 1960; Vol. 2, 1985). He was also the founder-editor of the journal Temps Modernes. His most important philosophical influences were French Hegelianism and the phenomenology of Husserl and Heidegger.

Sartre's existentialism, which he developed over the first part of his life, achieved a wide popularity, especially through his novels (La Nausée [Nausea], 1938), and ...