Jean-Paul Sartre was a French existentialist philosopher, dramatist, novelist and critic.

Sartre was born in Paris to parents Jean-Baptiste Sartre, an officer of the French Navy, and Anne-Marie Schweitzer, cousin of Albert Schweitzer. When he was 15 months old, his father died of a fever and Anne-Marie raised him with help from her father, Charles Schweitzer, who taught Sartre mathematics and introduced him to classical literature at an early age.

As a teenager in the 1920s, Sartre became attracted to philosophy upon reading Henri Bergson's Essay on the Immediate Data of Consciousness. He studied in Paris at the elite École Normale Supérieure, an institution of higher education which has served as the alma mater for multiple prominent French thinkers and intellectuals. Sartre was influenced by many aspects of Western philosophy, absorbing ideas from Immanuel Kant, Georg Wilhelm Friedrich Hegel and Martin Heidegger.

In 1929 at the École Normale, he met fellow student Simone de Beauvoir, later to become a noted thinker, writer, and feminist. The two, it is documented, became inseparable and lifelong companions, initiating a romantic relationship, though one that was not monogamous.

Together, Sartre and Beauvoir challenged the cultural and social assumptions and expectations of their upbringings, which they considered bourgeois, in both lifestyle and thought. The conflict between oppressive, spiritually-destructive conformity (mauvaise foi, literally, "bad faith") and an "authentic" state of "being" became the dominant theme of Sartre's work, a theme embodied in his principal philosophical work L'Être et le Néant (Being and Nothingness) (1944).

Sartre's most well-known introduction to his philosophy is his work Existentialism is a Humanism (1946). In this work, he defends existentialism against its detractors, which ultimately results in a somewhat incomplete description of his ideas. The work has been considered a popular, if over-simplifying, point of entry for those seeking to learn more about Sartre's ideas but lacking the background in philosophy necessary to fully absorb his longer work Being and Nothingness. One should not take the expression of his ideas contained here as authoritative; in 1965, Sartre told Francis Jeanson that its publication had been "une 'erreur.'"

He graduated from the École Normale Supérieure in 1929 with a doctorate in philosophy and served as a conscript in the French Army from 1929 to 1931.

In 1935 Sartre tried the psychedelic drug mescaline, which is found naturally in the peyote cactus of North America. By all accounts he had a bad experience. It is widely reported that the chapter 'Six o'clock in the evening' from 'The Nausea' is essentially a description of a bad mescaline trip.

The sudden revelation of the independent existence of objects (rather than merely the formulation of ideas in the observer's mind), the loss or irrelevance of names for those objects, and the indwelling horror of 'naked existence', are all very common elements of a negative visionary experience (see 'Heaven and Hell' by Aldous Huxley for an instructive comparison).

La Nausée and Existentialism
As a junior lecturer at the Lycée du Havre in 1938, Sartre wrote the novel La Nausée (Nausea) which serves in some ways as a manifesto of existentialism and remains one of his most famous books. Taking a page from the German phenomenological movement, he believed that our ideas are the product of experiences of real-life situations, and that novels and plays describing such fundamental experiences have as much value as do discursive essays for the elaboration of philosophical theories.

With this mandate, the novel concerns a dejected researcher (Roquentin) in a town similar to Le Havre who becomes starkly conscious of the fact that inanimate objects and situations remain absolutely indifferent to his existence. As such, they show themselves to be resistant to whatever significance human consciousness might perceive in them. This indifference of "things in themselves" (closely linked with the later notion of "being-in-itself" in his Being and Nothingness) has the effect of highlighting all the more the freedom Roquentin has to perceive and act in the world; everywhere he looks, he finds situations imbued with meanings which bear the stamp of his existence.

Hence the "nausea" referred to in the title of the book; all that he encounters in his everyday life is suffused with a pervasive, even horrible, taste -- specifically, his freedom. No matter how much he longs for something other or something different, he cannot get away from this harrowing evidence of his engagement with the world.

The stories in Le Mur (The Wall) emphasize the arbitrary aspects of the situations people find themselves in and the absurdity of their attempts to deal rationally with them. A whole school of absurd literature subsequently developed.

Sartre and World War II
In 1939 Sartre was drafted into the French army, where he served as a meteorologist. German troops captured him in 1940 in Padoux, and he spent nine months in prison — later in Nancy and finally in Stalag 12D, Treves, where he wrote his first theater piece: Barionà, fils du tonnerre, a drama concerning Christmas. Due to poor health (he claimed that his poor eyesight affected his balance) Sartre was released in April 1941.

Given civilian status, he recovered his position as a teacher of Lycée Pasteur near Paris, settled at the Hotel Mistral near Montparnasse at Paris and was given a new position at Lycée Condorcet, replacing a Jewish teacher, forbidden to teach by Vichy law. After coming back to Paris in May 1941, he participated in the founding of the underground group Socialisme et Liberté with other writers Simone de Beauvoir, Merleau-Ponty, Jean-Toussaint and Dominique Desanti, Jean Kanapa, and École Normale students.

In August, Sartre and Beauvoir went to the French Riviera seeking the support of André Gide and André Malraux. However, both Gide and Malraux were undecided, and this might be the cause of Sartre's disappointment and discouragement.

Socialisme et liberté disappeared soon and Sartre decided to write instead of being involved in active resistance. He then wrote Being and Nothingness, The Flies and No Exit, none of them being censored by the Germans. He also contributed to both legal and illegal literary magazines.

After August 1944 and the Paris Liberation, he was a very active contributor of Combat, a newspaper created during the period of clandestinity by Albert Camus, a philosopher and author who held similar beliefs. Sartre and Beauvoir remained friends with him until Camus turned away from communism, a schism that eventually divided them in 1951, after the publication of Camus' book entitled The Rebel.

Later, while Sartre was labelled by some authors as a resistant, the French philosopher and resistant Vladimir Jankelevitch criticized Sartre's lack of political commitment during the German Occupation, and interpreted his further struggles for liberty as an attempt to redeem himself.

When the war ended Sartre established Les Temps Modernes (Modern Times), a monthly literary and political review, and started writing full-time as well as continuing his political activism. He would draw on his war experiences for his great trilogy of novels, Les Chemins de la Liberté (The Roads to Freedom) (1945–1949).

Jean-Paul Sartre was the head of the Organization to Defend Iranian Political Prisoners from 1964 till the victory of the Islamic Revolution.

Sartre and Communism
The first period of Sartre's career, defined by Being and Nothingness (1943), gave way to a second period as a politically engaged activist and intellectual. His 1948 work Les Mains Sales (Dirty Hands) in particular explored the problem of being both an intellectual at the same time as becoming "engaged" politically.

He embraced communism, though he never officially joined the Communist party, and took a prominent role in the struggle against French colonialism in Algeria. He became perhaps the most eminent supporter of the Algerian war of liberation. He had an Algerian mistress, Arlette Elkaïm, who became his adopted daughter in 1965. He opposed the Vietnam War and, along with Bertrand Russell and other luminaries, he organized a tribunal intended to expose U.S. war crimes, which became known as the Russell Tribunal.

As a fellow-traveller, Sartre spent much of the rest of his life attempting to reconcile his existentialist ideas about self-determination with communist principles, which taught that socio-economic forces beyond our immediate, individual control play a critical role in shaping our lives. His major defining work of this period, the Critique de la raison dialectique (Critique of Dialectical Reason) appeared in 1960.

Sartre's emphasis on the humanist values in the early works of Marx led to a dispute with the leading Communist intellectual in France in the 1960s, Louis Althusser, who claimed that the ideas of the young Marx were decisively superseded by the "scientific" system of the later Marx.

Sartre and literature
During the 1940s and 1950s Sartre's ideas remained ambiguous, and existentialism became a favoured philosophy of the beatnik generation. Sartre's views were counterposed to those of Albert Camus in the popular imagination. In 1948, the Catholic Church placed his complete works on the Index of prohibited books. Most of his plays are richly symbolic and serve as a means of conveying his philosophy. The best-known, Huis-clos (No Exit), contains the famous line: "L'enfer, c'est les autres", usually translated as "Hell is other people".

Besides the obvious impact of Nausea, Sartre's major contribution to literature was the Roads to Freedom trilogy which charts the progression of how World War II affected Sartre's ideas. In this way, Roads to Freedom presents a less theoretical and more practical approach to existentialism. The first book in the trilogy, L'âge de raison (The Age of Reason) (1945), could easily be said to be the Sartre work with the broadest appeal.

Sartre after literature
In 1964, Sartre renounced literature in a witty and sardonic account of the first six years of his life, Les mots (Words). The book is an ironic counterblast to Marcel Proust, whose reputation had unexpectedly eclipsed that of André Gide (who had provided the model of litterature engagée for Sartre's generation). Literature, Sartre concluded, functioned as a bourgeois substitute for real commitment in the world. In the same year he was awarded the Nobel Prize for Literature, but he resoundingly declined it, stating that he had always refused official honors and didn't wish to align himself with institutions.

Though he was now world-famous and a household word (as was "existentialism" during the tumultuous 1960s), Sartre remained a simple man with few possessions, actively committed to causes until the end of his life, such as the student revolution strikes in Paris during the summer of 1968.

In 1975, when asked how he would like to be remembered, Sartre replied: "I would like [people] to remember Nausea, [my plays] No Exit and The Devil and the Good Lord, and then my two philosophical works, more particularly the second one, Critique of Dialectical Reason. Then my essay on Genet, Saint Genet...If these are remembered, that would be quite an achievement, and I don't ask for more. As a man, if a certain Jean-Paul Sartre is remembered, I would like people to remember the milieu or historical situation in which I lived,...how I lived in it, in terms of all the aspirations which I tried to gather up within myself."

Sartre's physical condition deteriorated, partially due to the merciless pace of work he put himself through during the writing of the Critique and the last project of his life, a massive analytical biography of Gustave Flaubert (The Family Idiot), both of which remain unfinished. He died April 15, 1980 in Paris from an edema of the lung.

Sartre lies buried in Cimetière du Montparnasse in Paris. His funeral was attended by some 50,000 people.

Sartre's atheism was foundational for his style of existentialist philosophy. In March 1980, about a month before Sartre's death, he was interviewed by an assistant of his, Benny Lévy, and within these interviews he expressed interest in Messianic Judaism. Some people apparently took this to indicate a religious conversion, however the text of the interviews makes it clear that he did not consider himself a Jew, and was interested in the ethical and "metaphysical character" of the Jewish religion, while continuing to reject the idea of an existing God.

In a separate 1974 interview with Simone de Beauvoir, Sartre said that he often saw himself "as a being that could, it seems, only come from a creator." However he immediately adds that "this is not a clear, exact idea..." and in preceding and following passages he makes it clear that he remains an atheist and finds in atheism a source of personal and ethical power.

Nevertheless, perhaps due in part to the fact that Sartre's interest in Jewish messianism was precisely a rejection of Marxist ideas which has previous played such a huge role in his thought, the validity of the Beny Levy interviews was disputed. Sartre's supporters were understandably reluctant to believe that he had so abruptly renounced a crucial part of his philosophy. However, shortly before his death, Sartre confirmed that the interviews were authentic.

Critiques

Munich 1972 and Israel
When eleven Israeli Olympians were killed by the Palestinian organization Black September in Munich 1972, Sartre referred to terrorism as a "terrible weapon but the oppressed poor have no others." He also found it "perfectly scandalous that the Munich attack should be judged by the French press and a section of public opinion as an intolerable scandal." (Sartre: The Philosopher of the Twentieth Century, Bernard-Henri Lévy, p.343).

Although this has been understood by many as an apologia for terrorism, these comments must be read together with others where he indicated that no means should be used which dehumanize its targets and disfigure its goal. He in fact identified as one of those "who affirm the sovereignty of the Israeli state and also believe the Palestinians have a right to sovereignty for the same reason..." He was also known for his strong opposition to anti-semitism.