Perhaps the best-known and most-quoted line from The Second Sex is the sentence, ‘One is not born, but rather becomes, a woman.’ Having examined throughout the first part of her book the various notions of the determination of women's lives, from biological to economic determinism, and the ‘myths’ by which these are sustained, de Beauvoir opens the second part with this statement of woman's becoming. ‘No biological, psychological, or economic fate determines the figure that the human female presents in society; it is civilization as a whole that produces this creature, intermediate between male and eunuch, which is described as feminine.’ Such in a succinct form is the basic thesis of the social constructionist paradigm, upon which an elaborate social, political, and ethical critique has been built by feminists seeking to understand, and to change, the conditions of the lives of women more fully and sensitively. Central to the claims of this paradigm is the recognition of the social construction of values, a recognition that constitutes at many points a challenge to the liberal paradigm, and that provides a distinctive approach to feminist moral and theological issues.

The roots of this way of thinking are to be found among those contemporaries of early liberal feminists who were more revolutionary in their political vision, more militant in political involvement, more socially conscious of the impact of working conditions, class structure, and family life on women, and more radical in the changes they sought in personal, social, and economic relations between women and men.