Near death, Jean-Paul Sartre made a remark to his lifelong companion, Simone de Beauvoir, that shocked her deeply.

"You are a good wife," he told her.

In de Beauvoir's reminiscences of Sartre's final years, the word "wife" is written in italics. She goes to some length to explain that the existentialist philosopher was in a state of semidelirium at the time. She describes the phrase itself as "very strange."

This incident, and the sense of amazement that it generated, illustrate two of the abiding claims to fame of the French writer Simone de Beauvoir, who died here today at the age of 78. As the author of "The Second Sex," which caused a scandal when it appeared in 1949 by condemning marriage as a form of slavery, she was a pioneer of the international women's movement. She was also the friend, nurse, confidant and biographer of France's greatest 20th-century philosopher.

De Beauvoir and Sartre weren't exactly a typical couple. They had what is usually referred to as "a close relationship" for more than half a century -- from their first meeting on the steps of the Sorbonne in 1929 right up to Sartre's death in 1980. Yet in all this time, they always used the formal vous, or second-person plural, to address each other, never the familiar tu. And, apart from a brief period after World War II when they shared a hotel room, they never lived together.

"What is the point of sharing the same roof when the world itself was our common property?" asked de Beauvoir in a remark that could be interpreted as either magnificently idealistic or insufferably priggish. She described knowing Sartre as "the greatest success of my life." He, in turn, paid tribute to her by writing: "I have experienced the world with you."

The critics have accused de Beauvoir of being humorless, distant and self-righteous. Her supporters viewed her as the beacon of women's liberation, a prophet. Either way, she was one of the last links with the great age of French literature, a symbol of a whole generation of politically committed intellectuals.

"The death of Simone de Beauvoir marks the end of an era," Prime Minister Jacques Chirac noted tonight in a tribute to an old political opponent on behalf of France's new conservative government. "Her committed style of literature was representative of an intellectual movement that marked our entire society for a certain period."

Like many French intellectuals, including Sartre himself, de Beauvoir traveled the road from pro-communist sympathies immediately after World War II to total disillusionment with Soviet-style communism. She described this process of ideological disenchantment in "The Mandarins," which won the prestigious Goncourt Prize in 1954, and is regarded by many as her finest novel.

While condemning totalitarianism, de Beauvoir remained loyal to the political left, supporting the election of Socialist President Franc,ois Mitterrand in 1981 and continuing to campaign for a variety of leftist causes. Last February, in one of her last public acts, she signed a petition expressing support for the then Socialist government's cultural policies.

De Beauvoir's most influential work was undoubtedly "The Second Sex," which sold more than a million copies in the United States alone. As a theoretical study of what it meant to be a woman, it developed what was then the radical thesis that "feminine" characteristics are socially acquired. "One is not born, but rather becomes a woman," she wrote. "It is civilization as a whole that produces this creature, intermediate between male and eunuch, that is described as feminine."

Drawing on existentialism, de Beauvoir argued that every human being must have the right to engage in freely chosen activity. She described marriage as "obscene" because it sought to transform what should have been a spontaneous attraction into a rigid system of rights and duties. In a country in which the family is widely regarded as the linchpin of the entire social system, her critique provoked an instant uproar.

In theory, her own relationship with Sartre was based on total freedom and total frankness. Together they pioneered the idea of the "trio," which usually consisted of the two of them plus one of Sartre's numerous women friends. In practice, however, the author of "The Second Sex" did not entirely manage to turn her back on bourgeois ethics: She displayed a perfectly human sense of jealousy at Sartre's affairs and proved adept at turning her rivals away.

Sartre once noted that "the wonderful thing about Simone de Beauvoir is that she has the intelligence of a man and the sensitivity of a woman," a sexist remark if ever there was one. He called her "the beaver," which he said summed up her tremendous appetite for work. Together in 1945 they founded Les Temps Modernes (Modern Times), a left-wing magazine that campaigned against French colonialism in Indochina and Algeria.

Perhaps the most serious criticism made of Simone de Beauvoir is that her view of the world was far too cerebral. She wrote extensively about the problems of bringing up children without ever having any children herself. Campaigning in favor of legalized abortion in France in 1972, she signed the so-called "Manifesto of the 343 Whores" who claimed they had had illegal abortions, only to acknowledge subsequently that she had never had an abortion.

At first impressed by the revolutionary potential of the Third World, she later became disillusioned when she discovered how women were actually treated in countries like Algeria. "I can't accept the way they oppress their women, veil them, impose forced marriages on them. [The Algerian writer] Frantz Fanon thought they would become emancipated after the Algerian war. On the contrary, they have been crushed," she complained to an interviewer in 1974.sk

If de Beauvoir remained faithful to an idea, it was to the idea of literature. "At the age of 15, I already wanted to be a famous writer. It seemed to be the only way of making a name for oneself." And, on another occasion, "A day I don't write leaves a taste of ashes."

She was also obsessed with the idea of death. In her most recent book "Adieux: A Farewell to Sartre," she described the gradual disintegration of her lifetime companion with agonizing detail. She also revealed that she had kept silent about his fatal cancer despite his numerous pleas to be told if he was close to death.

Insisting that her silence had saved the man she loved from avoidable agony, she wrote: "My silence does not separate us. His death does separate us. My death will not bring us together again. That is how things are. It is in itself splendid that we were able to live our lives in harmony for so long."