 The contractual understanding of marriage prompts the question as to why marital obligations should be fixed other than by spousal agreement. Immanuel Kant (1724–1804) combined a contractual account of marriage with an Augustinian preoccupation with sexual morality to argue that the distinctive content of the marriage contract was required to make sex permissible. In Kant’s view, sex involves morally problematic objectification, or treatment of oneself and other as a mere means. The marriage right, a “right to a person akin to a right to a thing,” gives spouses “lifelong possession of each other’s sexual attributes,” a transaction supposed to render sex compatible with respect for humanity: “while one person is acquired by the other as if it were a thing, the one who is acquired acquires the other in turn; for in this way each reclaims itself and restores its personality.” But while these rights, according to Kant, make sex compatible with justice, married sex is not clearly virtuous unless procreation is a possibility (Metaphysics of Morals, 1797–98, Ak 6:277–79, 6:424–427). Kant’s account of sexual objectification has had wide influence—from feminists to new natural lawyers. More surprisingly, given his views on gender inequality and the wrongness of same-sex sexual activity, Kant’s account of marriage has been sympathetically reconstructed by feminists and defenders of same-sex marriage drawn by Kant’s focus on equality, reciprocity, and the moral rehabilitation of sex within marriage (Herman 1993, Altman 2010, Papadaki 2010). Kant interestingly suggests that morally problematic relationships can be reconstructed through equal juridical rights, but how such reconstruction occurs is puzzling (Herman 1993, Brake 2005). Among other things, it is difficult to see how Kant’s insistence on equal marriage rights can be reconciled with his views on gender inequality (Sticker 2020).