Polygamy is alive and well in parts of America. According to researchers at Brigham Young University, there are 30,000 to 50,000 people currently living a polygamist lifestyle in the United States, many of them in sects that splintered from the mainstream Mormon church when it renounced polygamy in 1890. A separate study reported on NPR estimates that 50,000 to 100,000 Muslims in America may be quietly living polygamist lives. And around the world polygamy is a far more common phenomenon, especially in Africa and Asia. For the most part though, it is condemned in the West as being sexist towards women.
But Marina Adshade, an economics professor at Dalhousie University and the author of Big Think's "Dollars and Sex" blog, tells us that polygyny (the practice of a man having multiple wives) can actually be economically beneficial to women—and should not be outlawed by the government. Adshade bases her argument on the economic criterion for optimality called “Pareto efficiency.”
“A situation is Pareto efficient, or optimal if, and only if, no one can be made better off without making someone else worse off,” she explains. To demonstrate her point, Adshade asks us to consider a society with the following characteristics:
In forcing such a community to switch from polygyny to monogamy, the women would actually be the ones who lose out and the men would benefit, says Adshade.
Consider the following scenario: “A man makes a woman an offer of marriage and part of that offer is in terms of the standard of living of her and the children they will have together in the future. Say she receives two offers of marriage, one from a man who has plenty of resources and already has one wife (so that she will be wife number two) and a second from a man who has little resources and has no wives (so she will be the one and only wife). If she accepts the offer of the rich man over the poor man, and since she is acting in her own best interest, then she must prefer polygyny over monogamy. A change in marriage systems that forces her to be the only wife of the poor man necessarily makes her worse off. We know this because she could have accepted his offer in the first place and chose not to.
“The person in this story who benefits from the change from polygyny to monogamy though is the poor man who with the current system has no wife. He made a marriage offer to the woman and, since he is acting in his own best interest, if she had accepted the offer he would have been better off than he is without her. He had that offer refused though because she had a more appealing alternative. If there was a system of monogamy she might have accepted his offer because that alternative was no longer available.
“In polygynous societies with individual choice the truly disadvantaged are the poorer men who end up with no wives or families of their own. You can argue that the change to a monogamous society makes them better off but while it does so it makes the wives of the wealthy men worse off, so that change cannot meet the criterion for Pareto efficiency.” In other words, the shift from polygyny to monogamy would make women worse off, so the most economically sound policy would be to allow it to continue.
Stepping back from the economics of this debate, Adshade also argues that polygyny doesn’t inherently endanger the welfare of women and children. Firstly, she says it’s not true that women in polygamous societies have no say in marriage choices. “In fact, statistically, in societies without monogamy, there is actually slightly more opportunity for the bride and groom to either choose or have the right to refuse matches. Also there is evidence that in polygynous societies women have more control, not less, over the number of children they have.”
As for child welfare, she says, the results are mixed. But "there is plenty of evidence, despite the efforts of researchers to prove otherwise, that children in polygynous households are better off.” James Fenske, a professor at Oxford, is one such researcher who has found that polygyny in western Africa has historically lowered child mortality rates. “If their mothers choose their husbands based on their children’s best interests as well as their own we would expect this to be the case,” Adshade says.
Though reviled in the West, polygyny is actually quite common throughout the world. According to the Ethnographic Atlas, studying over a thousand societies from 1962-1980, there were over 1,000 polygamous societies, compared to just 186 monogamous ones. Adshade says that as long as women have a say in the matter, allowing polygyny to persist in those countries and communities where it already exists is actually better for women than forcing them to adopt a monogamous life. Plus polygynous relationships may actually be more stable than monogamous ones.
Why We Should Reject This
The case of the Fundamentalist Church of Jesus Christ of Latter Day Saints is evidence that women in polygynist societies often do not have the right to refuse marriage and are thus subjected to misogyny and often child abuse. Even putting this fact aside, Joseph Henrich, an anthropologist at the University of British Columbia, says there are good socioeconomic reasons why polygyny is illegal, even under the ideal situations that Adshade proposes.
If more people were allowed to pursue such a lifestyle—and Heinrich thinks they would “given what we know about both male and female mating preferences”—there would arise a large pool of unmarried males who were unable to attract a mate. Henrich believes this would lead to an increase in crime and antisocial behavior because, other things being equal, unmarried men tend to be more violent and more generally criminal than married men. Plus, this system would unfairly handicap poor and uneducated men, who could not compete with richer and thus more attractive mates who would be free to collect as many wives as they could handle.
Even for the men who successfully attract mates, their behavior is necessarily distorted by the practice of polygyny, Henrich says. Fiercer competition for wives promotes the idea of women as valuable objects rather than humans worthy of love, and as a result men feel the need to guard them more carefully. The same competition pushes the age at which girls are recruited for marriage lower. And men will also spend less time and fewer resources on individual wives and children: “Polygynous men invest less time in their offspring both because they have more offspring and because they continue to invest in seeking additional wives,” says Henrich.
— "The Link Between Polygyny and Child Mortality" [PDF] a 2009 presentation by James Fenke
— Joseph Henrich's affidavit to the Canadian Supreme Court providing his argument against polygyny [PDF]
— The Ethnographic Atlas Codebook published by World Cultures in 1986.