Born in Paris in 1905 to Jean-Baptiste Sartre, an officer in the French navy, and Anne-Marie Schweitzer, Jean-Paul lost his father at the tender age of fifteen months. He attended the Ecole Normale Superieure in Paris, one of the country's most prestigious schools, and graduated in 1929.
While at ENS, Sartre met the woman who was to become his lifelong companion - Simone de Beauvoir. He and Simone had a mutual arrangement and a partnership that remained in place for years. However, they never married, for Sartre did not believe in such a "bourgeois" institution. Also at ENS, Sartre met Emmanuel Mounier, Raymond Aron, Claud Levi-Strauss, Jean Hippolyte, and Simone Weil. He became deeply immersed in philosophy, and once out of school moved to Berlin to study the works of Martin Heidegger and Edmund Husserl. He began frequenting the Left Bank cafes of 1930s Paris, which were quickly becoming hives of intellectual activity, and fought briefly in World War II. Once back in Paris after being released from a German prison, Sartre joined the Resistance and wrote for the magazines Les Lettres Francaises and Combat. After the war, he founded Les Temps Modernes, a monthly literary and political review.
The influence of Husserl's phenomenological method on Sartre is apparent in one of the writer's first major publications, Imagination: A Psychological Critique (1936). Two years later, while teaching high school in the northern French port city Le Havre, Sartre published Nausea, a novel that earned him his first surge of fame. Sketch for a Theory of Emotions and L'Imaginaire: The Psychology of Imagination followed in 1939 and 1940, respectively.
By this point, the tenets of Sartre's existentialist philosophy were almost fully developed. Nausea tells the story of a man named Antoine Roquentin who discovers how excessively abundant the world is, and feels revulsion at this world and at his own body. Essentially, the novel argues that human life has no purpose, that existence is all there is to it - the fundamental principle of existentialism. Sartre soon made the acquaintance of Albert Camus, whose The Stranger (1942) became a touchstone of existentialist writing (though certain scholars place it in the "absurdist" camp and argue that Camus was never really an existentialist).
Sartre's Being and Nothingness (1943), perhaps his most important work of philosophy, mapped out his brand of existentialism, prioritizing existence over "essence" and arguing that life has no meaning beyond the goals we as individuals choose for ourselves. The freedom of man in a godless universe induces anxiety, and we all suffer from existential fear. Sartre recommends that human beings detach themselves from the things around them in order to give those things meaning. In the end, it is up to humans themselves to create meaning. We cannot search for it in notions of God, or in Kant's moral imperative. A year after the publication of this seminal work, Sartre's play No Exit was performed in Paris, just prior to Paris's liberation. A seemingly timeless work, No Exit owed much of its power to the desperation of an occupied France; its vision of three characters trapped in a particular version of hell echoed strongly with not just Sartre's philosophical leanings, but also with the political climate of the time.
It is important to note, however, that Sartre was far from a nihilist. Though his writings are often tinged with despair, Sartre himself was a tireless advocate of social change and, in a sense, a great optimist. A firm believer in human dignity, he remained a high school teacher for years and refused to wear a tie while on the job. He detailed his concept of social responsibility in Existentialism and Humanism (1946), and became deeply involved in leftist politics. Though never a member of the Communist Party, he expressed admiration for the Soviet Union and split with Camus due partly to the latter's indictment of Stalinism.
In 1956, however, things changed. As Soviet tanks entered Budapest, Sartre gave up hope for Communism and turned his back on the U.S.S.R. In "Le Fantome de Staline", an article he wrote for Les Temps Modernes, Sartre condemned the intervention, as well as the French Communist Party's submission to the Soviets. Critique of Dialectical Reason, published in 1960, proposed what is now known as Sartrian Socialism, a model by which Sartre demanded that Marxism recognize differences between one society and another and respect human freedom.
The Vietnam War provided another arena for Sartre's political convictions. He actively opposed the war, just as he had opposed France's war in Algeria, and in 1967 he headed the International War Crimes Tribunal, which had been established by Bertrand Russell to judge American military conduct in Indochina.
Sartre died in 1980 of edema of the lungs, leaving his last large work, L'idiot, incomplete.