The article gives a materialist interpretation of the first, second and third Marxist-feminist Theses through a critical analysis of the Unitary Theory of Social Reproduction. It argues that Social Reproduction Theory resorts to idealism and biologism when explaining male domination. A meta-critical incision will be carried out by studying the use Social Reproduction Theory makes of categories such as ‘production’, ‘reproduction’, ‘exploitation’ and ‘oppression’, in that these categories are addressed as historical while the categories of ‘women’ and ‘men’ are de-historicized and naturalized. According to Unitary Theories, ‘women’ are not material, historical products of patriarchy but biological beings (biologism) that have been culturally devalued (idealism). This leads to an essentialist ontology where ‘women’ and ‘men’ precede the relations of production that create them. This idea obstructs the formation of a materialist philosophy of praxis.