not a result of her biological disposition but of social relations, and that men's efforts to achieve their demands for control of women's labor and sexual faculties have gradually solidified and become institutionalized in the nuclear family. Through a Marxist historical perspective, Engels analyzes the widespread social phenomena associated with female sexual morality, such as fixation on virginity and sexual purity, incrimination and violent punishment of women who commit adultery, and demands that women be submissive to their husbands. Ultimately, Engels traces these phenomena to the recent development of exclusive control of private property by the patriarchs of the rising slaveowner class in the ancient mode of production, and the attendant desire to ensure that their inheritance is passed only to their own offspring: chastity and fidelity are rewarded, says Engels, because they guarantee exclusive access to the sexual and reproductive faculty of women possessed by men from the property-owning class. In the late nineteenth and early twentieth centuries, both Clara Zetkin and Eleanor Marx were against the demonization of men and supported a proletariat revolution that would overcome as many male–female inequalities as possible. In this way, a politic of solidarity was seen as the means to enact a socialist platform. As their movement already had the most radical demands in women's equality, most Marxist leaders, including Clara Zetkin and Alexandra Kollontai, counterposed Marxism against bourgeois feminism, rather than trying to combine them. Orthodox Marxists argue that most Marxist forerunners claimed by feminists or Marxist feminists including Clara Zetkin and Alexandra Kollontai were against capitalist forms of feminism. They agreed with the main Marxist movement that feminism was a bourgeois ideology counterposed to Marxism and against the working class. Instead of feminism, the Marxists supported the more radical political program of liberating women through socialist revolution, with a special emphasis on work among women and in materially changing their conditions after the revolution. Orthodox Marxists view the later attempt to combine Marxism and feminism as a liberal creation of academics and reformist leftists who want to make alliances with bourgeois feminists. For instance, Alexandra Kollontai wrote in 1909: For what reason, then, should the woman worker seek a union with the bourgeois feminists? Who, in actual fact, would stand to gain in the event of such an alliance? Certainly not the woman worker.Kollontai was a prominent leader in the Bolshevik party in Russia, defending her stance on how capitalism