True Love Is The Most Important Thing In The World: A Coasian/Evolutionary Approach

My wife and I took the 6 train down to City Hall five years ago today. It’s been good so far. Half a decade later, we’ve survived three kids, two cross-country moves, some death, and other sundry issues. But we had basically the right idea when we got married. Here’s what I posted on Facebook the day of:

Marriage is really important, and I think we should make it legal again.

Technically you can fill out some paperwork and get married — Pamela and I just did. And of course you can have a wedding.* What you can’t reliably do in most states is make a legally binding, socially binding commitment to join yourself at the hip to another person — to be a family unit, not two atomized individuals who happen to share a lot of stuff.

As game theorists love to point out, the right to be sued is a valuable one. Without it, you can’t make credible promises. Similarly, the right to get married such that you can’t get unmarried without Herculean effort is a valuable one. The existence of no-fault divorce weakens that. You just can’t write a marriage contract that’s as permanent as used to be standard, and shorter-term contracts raise time preference and thus reduce investment in the future.

And investing in the future is a pretty big deal! In a way, marriage is a legal recognition of a biological fact: once two people have three or more kids, their largest genetic investment is in the kids they share, not in themselves.** Long-term reproductive pair bonds whose offspring follow the same path creates a sort of rolling decrease in time preference. Not only would you expect people with kids to think one generation further ahead on average, _but_ within large groups that behave that way, there’s positive selection pressure on thinking even further ahead. One generation of kids should shift the locus of your net present value calculation forward by about a generation, but kids followed by the expectation of grandkids and great-grandkids should keep dragging it further forward.***

And suddenly a bunch of weird traditionalist virtues become more salient.

When social conservatives said that the family, not the individual, was the fundamental unit of civilization, libertarian-me used to roll his eyes. It’s not like “a family” has wants, or agency. “A family” is just the average of two people, who could want different things and behave in different…