Jean-Paul Sartre

Jean-Paul Sartre's greatest contribution was his uncompromising affirmation of human freedom. "Existence precedes essence" means we have no fixed nature; we become who we are through acts and choices. In post-war Europe, where old certainties lay shattered, this offered a new compass.

Born in Paris in 1905, Sartre lost his father at two and was raised among the books of his grandfather Karl Schweitzer. Despite severe strabismus he excelled at the Ecole Normale Superieure, topping the philosophy agregation. There he met Simone de Beauvoir; they rejected marriage, forging an open partnership embodying existentialist principles.

Berlin in the 1930s introduced him to Husserl's phenomenology. Nausea (1938) dramatized existential contingency. Under occupation he published Being and Nothingness (1943), defining consciousness as perpetually free. "Man is condemned to be free": every evasion is bad faith. No Exit's "Hell is other people" warns what happens when others' gazes define us.

Captured as a soldier and released, Sartre co-founded "Socialism and Liberty" and spent his life practicing engagement. Through Les Temps Modernes he championed Algerian independence, protested Vietnam, and backed May 1968. He refused the Nobel, insisting a writer must not become an institution.

Critics said radical freedom ignored social constraints. Structuralists questioned subject-primacy. Sartre turned to Marxism in Critique of Dialectical Reason (1960). He lost his eyesight in 1973 but continued dictating until his death in 1980. Fifty thousand Parisians marched at his funeral.