Simone de Beauvoir

Simone de Beauvoir was a notable French philosopher and feminist theorist. She is most well-known for her revolutionary book "The Second Sex" (1949) in which she lays the underpinnings for second-wave feminism.

In "The Second Sex," Beauvoir establishes that sex and gender are different, and gender is a social construct. She challenges the social inequality of women as inferior to men—the "other" to their default, the "second" to their "first."

Her criticisms of gender roles and the ways enforced femininity limits women's freedom directly builds on her existentialist philosophy.

Although her work focuses mainly on gender and rarely considers race and other intersecting identities, her existentialist ethics (discussing absolute freedom vs. the constraints of circumstance) welcomes intersectionality into her work while engaging it with a critical eye.