What is the importance of the second sex by de beauvoir?

Simone de Beauvoir states that every civilisation creates a Self (those living within the accepted realms of society) and simultaneously an Other. The Other is seen as inferior to the Self and this dichotomy is most commonly used in race and gender politics. So, de Beauvoir is arguing that men are the Self and women are the Other, as women were still widely treated as second-class citizens at the time of writing.