This article begins the task of assessing polygamy as a moral ideal. The structure of traditional polygamy, in which only one central spouse may marry multiple partners, necessarily yields two inequalities. The central spouse has greater rights and expectations within each marriage and greater control over the wider family. However, two alternative structures for polygamy can remove these inequalities. In polyfidelity, each spouse marries every other spouse in the family. In “molecular” polygamy, any spouses may marry a new spouse outside the family. These new models of polygamy face additional difficulties, but they can be egalitarian in principle.

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C. Two Necessary Inequalities in Traditional Polygamy

Traditional polygamy, in contrast, can never be equal. In traditional polygamy, only one person in the family may marry multiple spouses.16 This structural feature is present in most cultural traditions of polygamy, from Mormon and Islamic polygyny to Tibetan polyandry. Within this structure, it is conceptually impossible to construct an egalitarian ideal of polygamy. Spouses in traditional polygamous marriages cannot treat one another as equals, even if the obvious sexual inequality is removed because the society permits polyandry and even if the spouses are perfectly virtuous and strive to treat one another as equals.

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III. CONCLUSION

Traditional polygamy is inherently unequal. Its hub-and-spoke structure creates two inequalities that would remain even if the sexual discrimination disappeared and spouses were fully virtuous: peripheral spouses will always have greater commitments within their marriage and less control within their family. It is only possible for polygamous spouses to treat one another as equals if each spouse marries every other spouse in the family or if peripheral spouses may marry outside the family. Polyfidelity and molecular polygamy significantly revise the traditional conception of polygamy and challenge our understanding of marriage, but they at least eliminate the inequalities that will otherwise pervade polygamous marriages.