Simone de Beauvoir (1908–86) was one of the 20th century’s most influential intellectuals. In addition to writing “the feminist Bible,” The Second Sex, she was a philosopher, a prize-winning writer, and a feminist and anti-colonial campaigner whose activism led to dramatic shifts in political opinion and changes in legislation. She was also one of the century’s most infamous women, due to her unconventional and misunderstood relationship with the playboy philosopher Jean-Paul Sartre.

In the past decade, new diaries, manuscripts, and letters have become available that show both Beauvoir’s intellectual independence and originality, and the sexist onslaught she faced for saying what she did. From The Second Sex onward, critics continuously condescended to remind Beauvoir that women didn’t need feminism anymore. Why did she insist on being so passé? What was it she thought women still needed?