Simone Lucie Ernestine Marie Bertrand de Beauvoir was a French existentialist philosopher, writer, social theorist, and feminist activist. Though she did not consider herself a philosopher, nor was she considered one at the time of her death, she had a significant influence on both feminist existentialism and feminist theory.

Existentialism is a form of philosophical inquiry that explores the issue of human existence. Existentialist philosophers explore questions related to the meaning, purpose, and value of human existence. Common concepts in existentialist thought include existential crisis, dread, and anxiety in the face of an absurd world and free will, as well as authenticity, courage, and virtue.