On Marriage and Divorce (Part 2)

Monogamy, Gender Pay Gap and Testosterone

Click Here for Part 1

The power of culture is generally understated. Take dating and marriage for example. What are the social norms that we all subscribe to? You go out, you meet a nice girl, you date for a while, it starts to get serious, then there is discussions on exclusivity. Eventually there may even be marriage and later kids. This is a pretty standard script that we all engage with.

It’s a script not even enforced by a religious decree anymore. We’re living in a post religious world. This is the structure people want from the bottom up. Without any top down power shaping their habits.

This structure is even getting more traditional for certain upper classes. Take a look at how attitudes toward divorce among the affluent and educated have gotten more conservative over the years. This is what people want.

Marriage in Antiquity

Humans, unlike animals, can create an institution, and then scale that institution up to have a profound effect on society. For example, the Christian Church introduced a stricter form of monogamy that had already existed. It attempted to do two things with this new marriage program:

1) it constrained men from seeking sex outside of marriage - from visiting prostitutes or having mistresses. To accomplish this, the Church worked to end prostitution and sexual slavery while creating social norms that motivated communities to monitor men’s sexual behavior and make violations public. Before, men could legally have extra-marital sex with slaves and prostitutes in ancient Rome and Greece. There were adultery laws, but that meant sleeping with another married woman.

2) the Church made divorce difficult. This was in contrast to the norms back then. One or both parties to a Roman marriage simply had to consider themselves no longer married. It was deemed advisable to notify the other party, but not legally required that one do so. Towards the latter part of the republic, and under the empire, divorces became very common. Cicero speaks of Paula Valeria as being ready to serve her husband, on his return from his province, with notice of divorce. As divorce became more common, attempts were made to check it indirectly, by affixing pecuniary penalties or pecuniary loss on the party whose conduct rendered the divorce necessary. This was part of the object of the lex Papia Poppaea.


Cultural norms not only order society, but they manipulate us biologically. Take for instance the hormone Testosterone. Humans possess a physiological system that regulates men’s testosterone, along with other aspects of our psychology, by relying on cues related to mating opportunities, parenting demands , and status competition. When necessary, T levels rise to prepare males to compete for status and mates. But, when it’s time to build nests and nurture offspring, T levels decline.

Married men, whether fathers or not, have markedly lower testosterone levels than single males. It makes sense. Lower levels of testosterone increase the likelihood that men will stay home and care for their wives and kids, while decreasing the likelihood they will go out drinking with the guys and chase other women.

Crucially, this only applies to monogamous marriage.

In polygynous societies, a higher percentage of men never experience the testosterone declines observed in men from monogamous societies. In societies with monogamy, which is most, but not all of societies on earth. Getting married lowers a man’s testosterone. If he divorces, his T levels climb again.

Aggregating these effects across an entire population, we can being to see how monogamous norms suppress testosterone at a societal level. By prohibiting higher-status men from monopolizing potential wives, monogamous norms allow many more lower-status men to both get married (pair-bond) and father children. Thus, monogamous marriage ensures that a higher percentage of men will experience the lower-T that attends both monogamous marriage and caring for children

Testosterone Replacement Therapy

But the story doesn’t end there. During the last 10-15 years there has been an explosion of men taking Testosterone Replacement Therapy. Men, whose T levels would be diminishing because they engage with the monogamous social norms of their society and naturally aging. Essentially, we’re using science to get around a practice of culture.

What are going to be the effects of this new phenomenon? At the individual level? At the scaled up society level?

Nobody knows. It’s an experiment. But we’ll find out soon because this phenomenon has been growing fast in recent years.

Why Not Polygynous Marriage?

Most anthropologically known hunter-gatherer societies permit polygynous marriage and it persists at low to medium frequencies. Not surprisingly, it’s always the prestigious men - the great shamans, hunters, and warriors who attract multiple wives, though few marry more than about four women.

We kind of do have a polygnous bias. It arises from fundamental asymmetries in human reproductive biology. Over our evolutionary history, the more mates a man had, the greater his reproduction. By contrast, for women, simply having more mates didn’t directly translate into greater reproduction. Women have to carry their own fetuses, nurse their own infants and care for their toddlers.

One way to obtain some of this help was to form a pair-bond with the most capable, resourceful and highest status man she could find by making it clear to him that her babies would his babies. For these reasons, natural selection has shaped our evolved psychology in ways that make men, particularly high status men, favorably inclined toward polygynous marriage. It isn’t shocking that men have certain psychological inclinations toward polygnyny.

As societies adopted farming and began to scale up in size the, the emergence of large inequalities among men greatly exaggerated the intensity of polygynous marriage. It leads to a large pool of low-status unmarried men with few prospects. This sparks war and violence.

Moreover, making polygyny illegal also stops women from choosing the same high status man. This leads to a more stable society.

Friendship and Marriage

Americans have fewer friends than they used to decades ago.

15% of men and 10% of women have no close friends.

I've moved to new cities as an adult a few times. It's much tougher to get into a new friends group than it is just to date women and get into a relationship. Friends groups are inherently hostile to outsiders. But single women want to be in relationships.

It’s no coincidence that has people have fewer friends over the years while also the rise of the “best friend is your spouse” movement happening at the same time

The prevailing conception of an ideal spouse is essentially someone who is everything you want in one person - best friend, lover, soulmate, co-parent, intellectual partner, etc. Experience alone is sufficient to demonstrate this is an unrealistic expectation. Approaching your spouse as a “best friend” sounds good only at first glance, and is damaging long-term. Being someone’s “best friend” requires sacrifices that shouldn’t be required of spouses. There is a certain spiritual familiarity and overbearing closeness you can only afford between friends, and which you shouldn’t expect or impose on your spouse.

Best Pals

"I had never heard a woman call her husband by his last name"

Consider maybe there's a reason for that.

Source of excerpt is Mindy Kaling's memoir Is Everyone Hanging Out Without Me?

Published 2011.

Poehler and Arnett divorced in 2012 after nine years of marriage.

Stay At Home Moms

One of the biggest flexes someone can say to you is that their wife (or husband) does not work. They can stay home and raise the kids. Most people are in a two paycheck homes now. Due to cost of living. A husband and wife working is a fact of life for most everyone.

It turns out having a stay at home parent is U-shaped. It mainly applies to the rich and poor.

The rich and the poor actually have more in common than you think:

  • Who is president actually makes a difference in your life

  • Having a collection of old cars

  • First name basis w/ local law enforcement

  • Never having to set your alarm clock

  • Gets free clothes

  • Needs to be aware of charitable organizations

Close to half of mothers whose husbands earn $250,000 or higher a year (46%) are not in the labor force. On the other end of the income spectrum, 35% of mothers whose husbands make less than $25,000 a year are stay-at-home moms. Mothers married to husbands with an income between $50,000 and $75,000—the group that includes the median husband’s income of $60,000—are the least likely to stay at home; only 25% of them are out of the labor force.

Interestingly, we see this same type of U-shape with people having kids.

Gender Pay Gap

For most of my life I have heard that women earn less than men. Is any of that true? A little bit. “The Declining Earnings Gap Between Young Women and Men in the United States 1979-2018” sets out to update our understanding of these work/family/income dynamics.

Women entering the workforce in 1979 could expect to earn only 60% of what men earned, the same as they had for the previous 20 years. After 1980, their position improved dramatically, plateauing at 77% for several years in the first decade of the 21st-century and jumping to 82% in 2018.

During the decades examined by the authors, women went to college in ever larger numbers. By 1980, the percentage of women on campus actually surpassed that of men; as of 2018, 37.5% of women aged 25 to 29 had completed four years or more of college, compared with 30.7% of men in the same age group. Women’s advantage in postgraduate degrees was even higher. As they pursued higher education and better opportunities in the labor market, women put off marriage and childbearing considerably later than their mothers did.

Marriage Penalty?

In the not so distant past, once a woman tied the knot, chances were that she would see her paycheck shrink in comparison to her unmarried peers; that was true even if she had no children. This is no longer the case. By 1989, women’s marriage disadvantage had disappeared, and now, two decades later, it has turned into the opposite.

But do mothers even want to work full time, given the choice? No. Having children is a major life-changing event for both men and women. And priorities in life can also change because of parenthood. When asked what their ideal work situation would be, only 28% of American married mothers say it is full-time work, whereas 43% of married women without children say so, according to our new survey.

Twenty-something wives now earn 6% more than unmarried women. While marriage no longer puts a damper on women’s earnings, that’s not the case for motherhood.

Mothers, at least those who have children in their late twenties, continue to make less than childless women. Similarly, there remains a substantial gender gap among full-time working young adult men and women who are both married and have children. Still, the disparity has shrunk markedly over time. That gender gap stood at 40% in 1979; by 2018, it was down to 21 percent. Notably, median earnings grew by 19% among all women, but the groups who experienced the largest gains were those who were married and those who were married with children; incomes improved by 24% for both of these groups.


Up until the mid-20th century, married men typically had more education than their wives. Today, that norm has reversed: when it comes to diplomas, women “partner down” more than men do. And whereas in the past, hypergamous couples —wives with more education than their husbands—were at greater risk of divorce, this is no longer the case.

But hypergamy turns out to be a stubborn thing. It seems that the highly-credentialed alpha female still prefers a mate above her pay grade. In one of the most widely-cited papers on the subject, demographer Yue Qian compared couples in the 1980 Census and in 2012 American Community Survey. She found that during the intervening decades, though wives became more likely to marry down in terms of educational achievement, “the tendency for women to marry men with higher incomes than themselves persisted.” In fact, women with the same or more education than their husbands were more likely to marry up.

Relationship Tips

Both Musonius Rufus (The Chief End of Marriage) and later Plutarch (Advice to Bride and Groom) agreed that the foundation of marriage is the mutual affection and care expressed by the couple to each other and their offspring. But both authors, although they acknowledged the potential for virtue and seek an “elevated” form of conjugal relationship based on companionship.