My proposition is that marriage is the institution by which unpaid work is extorted from a particular category of the population, women-wives. This work is unpaid for it does not give rise to a wage but simply to upkeep. These very peculiar relations of production in a society that is defined by the sale of work (wage-labour) and products, are not determined by the type of work accomplished. Indeed they are not even limited to the production of household work and raising children, but extend to include all the things women (and also children) produce within the home, and in small-scale manufacturing, shopkeeping or farming, if the husband is a craftsman, tradesman or farmer, or various professional services if the husband is a doctor or lawyer, etc. The fact that domestic work is unpaid is not inherent to the particular type of work done, since when the same tasks are done outside the family they are paid for. The work acquires value - is remunerated - as long as the woman furnishes it to people to whom she is not related or married.
The valuelessness of domestic work performed by married women derives institutionally from the marriage contract, which is in fact a work contract. To be more precise, it is a contract by which the head of the family - the husband - appropriates all the work done in the family by his children, his younger siblings and especially by his wife, since he can sell it on the market as his own if he is, for example, a crafstmand or farmer or doctor. Conversely, the wife's labour has no value because it cannot be put on the market, and it cannot be put on the market because of the contract by which her labour power is appropriated by her husband. Since the production intended for exchange - on the market - is accomplished outside the family in the wage-earning system, and since a married man sells his work and not a product in the system, the unpaid work of women cannot be incorporated in the production intended for exchange. It has therefore become limited to producing things which are intended for the family's internal use: domestic services and the raising of children.
Christine Delphy, Close to Home, 1976