Simone de Beauvoir was a French existentialist philosopher, public intellectual, and social theorist. She wrote novels, essays, biographies, an autobiography in several volumes, and monographs on philosophy, politis, and social issues. She is now best known for her metaphysical novels, including She Came to Stay and The Mandarins, and for her 19949 treatise The Second Sex, a detailed analysis of women's oppression and a foundational tract of contemporary feminism. She is also noted for her lifelong polyamorous relationship with Jean-Paul Sartre.