Richard Hanania on Henrich's WEIRDest People on Marriage Practices

We have gone over the likelihood here that the discouragement of cousin marriage has had an enormous influence on Western Civilisation. Richard Hanania does a quick summary of Joseph Henrich's book (and makes a plug for Garett Jones Hive Mind, which we have just mentioned as well) about Western Educated Industrialised Rich and Democratic nations being significantly different from the rest of the world, and then comments on this himself. I liked it quite a bit, the third thing in a row i have liked by Hanania after dismissing him about a year ago. So i think I have to call myself wrong about him at this point.

Ultimately, Henrich traces the success of the West back to the sex and marriage taboos of early Christianity. The book highlights how obsessed early Christian leaders were with preventing incest, and just how rare this concern has been historically. An appendix to the book lists milestones in the process, beginning with the Synod of Elvira in 305-306 AD decreeing that a man could not take communion if he married his dead wife’s sister, to bans on marrying family members that started with close relatives like first cousins and nieces and expanded to include sixth cousins by the eleventh century in a system that covered not only blood relations, but affines (i.e., in-laws, step-children, etc.) and spiritual kin (godmothers, etc.).

And there's historical linguistics to boot. 

A fascinating line of evidence documenting the development of changing family norms can be found in the linguistic record. Earlier in their history, European languages had terms for things like “mother’s sister” or “male cousin on my dad’s side” instead of just saying “aunt” or “cousin.” Such distinctions matter in societies in which clans and extended family relations are important and descent is traced through either the male or female line alone, and so these kinds of words are still used in modern languages such as Arabic. They would disappear across Europe, first in the Romance languages like French and Italian around 700, and then German and English by around 1100.

I also discussed this, and the focus on monogamy and its importance both culturally and economically, in the series on polygamy from this fall, specifically the  post on Old World Demographics and Religious Practices. Monogamy and forbidding incest reduce the power of elders, make society more mobile and individualistic, and reduces dependence on kinship networks.

Hanania becomes quite critical of the book on what he considers some less-important points - reliance on some suspect research - and a major one - neglect of actual genetics - but in the end pronounces it valuable. There's just so much out there proving out that folks don't want to be true, isn't there?