To be fruitful and multiply

To be fruitful and multiply

Over at The Wall Street Journal Bryan Caplan has an op-ed, The Breeders’ Cup: Social science may suggest that kids drain their parents’ happiness, but there’s evidence that good parenting is less work and more fun than people think. Bryan Caplan makes the case for having more children. Much of the op-ed focuses on behavior genetic insight as to the relative lack of long term importance of shared environment (read: parental environmental input). But the section on happiness and diminishing returns on the misery cost of children piqued my interest:

…closer look at the General Social Survey also reveals that child No. 1 does almost all the damage. Otherwise identical people with one child instead of none are 5.6 percentage points less likely to be very happy. Beyond that, additional children are almost a happiness free lunch. Each child after the first reduces your probability of being very happy by a mere .6 percentage points.


The op-ed is a precis of Caplan’s next book, Selfish Reasons to Have Kids. Being an economist he focuses on rational individual behavior, but I want to point to another issue: group norms. In the left-liberal progressive post-graduate educated circles which I come into contact with in the USA childlessness is not uncommon, and bears no stigma (on the contrary, I hear often of implicit and explicit pressure on graduate students to forgo children for the sake of maximizing labor hour input into research over one’s lifetime from advisors). On the other hand, the norm of a two-child family is also very strong, and going above replacement brings upon you a fair amount of attention. The rationale here is often environmental, more children = more of a carbon footprint. But my friend Gregory Cochran has stated that as an individual who is well above replacement whose social milieu is more conservative that he perceives that more than two children is also perceived as deviant in Middle American society. In other words, the reasoning may differ, but the intuition is the same (in Italy the reasoning mostly involves the cost of raising children from the perspective of parents, both in cash and time).

The numbers in the General Social Survey tell the tale. In 1972 42% of adults had more than 2 children. In 2008 32% did. More relevantly in 1972 47% of adults between the ages of 25 and 45 had more than 2 children. In 2008 the figure for that age group is 27% for those with more than 2 children.

Of course the numbers mix up a lot of different subcultures. One anecdote I’d like to relate is a conversation I had with a secular left-of-center university educated couple. They expressed the aspiration toward 4 children. I asked them out of curiosity about the population control issue, and they looked at me like I was joking. It needs to be mentioned that they weren’t American, rather they were from a Northern European country which seems on the exterior to resemble the United States very much. But it reminds us of the importance of group norms in shaping life choices and expectations, the implicit framework for our explicit choices.

All that goes to my point that Bryan Caplan’s project will be most effective among demographics geared toward prioritizing individual choice, analysis and utility maximization, as opposed to relying upon the wisdom of group norms. Economists, quantitative social science and finance types, libertarians, etc.

Note: Here’s Will Wilkinson’s rebuttal to Caplan’s empirical case in regards to happiness.

Razib Khan