This is actually a (very) extended book review. I hardly have to say it’s lengthy: this is Scott Alexander we’re talking about. He writes basically the longest posts on the entire internet. So if you click through, be aware, you aren’t going to read the whole post in two minutes.
The book in question is:
The Secret of Our Success: How Culture Is Driving Human Evolution, Domesticating Our Species, and Making Us Smarter, by Joseph Henrich. I’ll add that after reading (part of) Scott’s review, I’ve ordered the book. In paper. I don’t like stuff like this on Kindle, where it’ll probably get shuffled toward the back of the pile of electrons and I’ll forget it’s there. I want this on the coffee table, where I’ll pick it up and dip into it whenever I’m in the mood.
Here is where I stopped reading the post and just bought the book:
Rationalists always wonder: how come people aren’t more rational? How come you can prove a thousand times, using Facts and Logic, that something is stupid, and yet people will still keep doing it?
Henrich hints at an answer: for basically all of history, using reason would get you killed.
A reasonable person would have figured out there was no way for oracle-bones to accurately predict the future. They would have abandoned divination, failed at hunting, and maybe died of starvation.
A reasonable person would have asked why everyone was wasting so much time preparing manioc. When told “Because that’s how we’ve always done it”, they would have been unsatisfied with that answer. They would have done some experiments, and found that a simpler process of boiling it worked just as well. They would have saved lots of time, maybe converted all their friends to the new and easier method. Twenty years later, they would have gotten sick and died, in a way so causally distant from their decision to change manioc processing methods that nobody would ever have been able to link the two together.
Henrich discusses pregnancy taboos in Fiji; pregnant women are banned from eating sharks. Sure enough, these sharks contain chemicals that can cause birth defects. The women didn’t really know why they weren’t eating the sharks, but when anthropologists demanded a reason, they eventually decided it was because their babies would be born with shark skin rather than human skin. As explanations go, this leaves a lot to be desired. How come you can still eat other fish? Aren’t you worried your kids will have scales? Doesn’t the slightest familiarity with biology prove this mechanism is garbage? But if some smart independent-minded iconoclastic Fijian girl figured any of this out, she would break the taboo and her child would have birth defects.
I must say, I think this smart, independent-minded, iconoclastic girl is obviously a YA protagonist. Except that in YA literature, the protagonist is always right if she breaks away from tradition, whereas in the real world, apparently she may very well discover she was wrong, and now her babies have birth defects. Oops.
Anyway, it’s a very interesting review with commentary, and I’m pretty sure the book is going to turn out to be even more fascinating when I read it myself.