Commenter Lion of the Judah-sphere is a black national merit finalist. According to the Westhunter blog, black national merit honorees are extremely rare, so I’m quite honored to have Judah-sphere among my regular commenters, and his calm objective rationality brings with it a certain gravitas. The great Judah-sphere writes:

The problem is that even if crystallized g [acquired knowledge] does include impacts from education/environment, it doesn’t mean that crystallized intelligence is any less genetic. What I mean is that genetics cause you to seek out education and good environments. Someone with low crystallized ability could be put at Eton or given the best private education, but because they aren’t genetically suited to seeking out information, their crystallized intelligence will hardly go up at all. Someone with high crystal. could be put in a 1st world ghetto and they’ll seek out knowledge anyhow despite being in a shitty environment. SO it’s kinda like GxE interactions, but the environments are caused directly by genes.

As commenter bucephalus noted, the phenomenon Judah-sphere is describing is known as “G-E active covariance”, and might be one of the most important reasons for the high heritability of crystallized tests.

As I was having lunch at the Chateau Laurier this afternoon with some friends I have known since we were toddlers (we’re now all in our thirties), I mentioned this argument:

“It’s bullshit,” exclaimed one of them (paraphrasing from memory):

All of us here are really really smart guys, but it’s because of the environment we were born in, not the environment we chose.  We grew up in like the best suburb of the most elite city of the most educated country of the World’s richest continent…I go to the United States all the time and I don’t care whether it’s the inner-city or the Ivy League,  nobody there had the kind of education we had…they don’t talk like we do, they don’t pronounce words like we do, they don’t view the World like we do…I can’t explain it, but you know it when you see it…there’s a level of sophistication you see among the people in this city that you just don’t get anywhere in the United States.  So it’s not our genes, it’s our environment.

His wife enthusiastically agreed, citing some MacCleans article and how Canadians are better, richer, taller and smarter than Americans.

“Yes,” I replied (paraphrasing from memory):

But from the moment a baby can talk; the baby that has the genes to talk earlier is going to be talked to more, is going to be taught to read earlier.  If he also has the genes to read early, he’s going to be taught to write early, and if he has the genes to write early, he’s probably going to end up in either a stimulating college or a stimulating job…so the environment is constantly testing our genes, and every-time they pass, we get to an even better environment, so even people who start out in different environments, often end up in the same ones if they have the same genes.

And then I had an epiphany…that’s yet another major reason why verbal IQ is more heritable than spatial IQ, despite being much more culture loaded.  In my opinion, verbal IQ is artificially improved by the social environment, but spatial IQ is genuinely improved by the biological environment, but since genes for verbal IQ cause good social environments, while biological environments are mostly luck (prenatal conditions, concussions etc), the gene-environment correlation becomes much higher for verbal IQ, resulting in higher heritability.

Advertisements