In the West, rich and powerful men regularly swap older wives for younger ones, thus monopolizing the prime reproductive years of several women. But that allows for a few wives in sequence, not several at the same time.
There are those who argue that polygamy should be made legal in America. If the constitution demands that gay marriage be allowed, then surely it is unconstitutional to disallow plural marriage, they argue.
Because it is illegal in most rich countries, many Westerners underestimate how common polygamy is. More than a third of women in West Africa are married to a man who has more than one wife. Plural marriages are plentiful in the Arab world, and fairly common in South-East Asia and a few parts of the Caribbean.
The cultures involved are usually patrilineal: i.e., the family is defined by the male bloodline. And they are patrilocal: wives join the husband’s family and leave their own behind. Marriages are often sealed by a payment of a brideprice from the groom’s family to the bride’s. This is supposed to compensate the bride’s family for the cost of raising her.
Polygamy tends to raise the age at which young men get married; it takes a long time to save enough money. At the same time, it lowers the age at which women get married. All but the wealthiest families need to “sell” their daughters before they can afford to “buy” wives for their sons.
Valerie Hudson of Texas A&M University and Hilary Matfes of Yale have found that an inflated brideprice is a “critical” factor predisposing young men to become involved in organized group violence for political purposes.”
Proponents of polygamy offer two main arguments. One is that it is blessed in the Koran. The other is that it gives women a better chance of avoiding spinsterhood.
Polygamy is bad for children. A study of 240,000 children in 29 African countries found that those in polygynous families were more likely to die young.1
Marriage understood as a comprehensive union can exist only between two persons, and never more than two persons. Society, therefore, has good reason not simply to proscribe polygamy, but to endorse monogamy.2
2 Kaczor, Christopher. The Witherspoon Institute. May 21st 2012. Retrieved from: http://www.thepublicdiscourse.com/2012/05/5338/.