A recent entry from the West Hunters blog (written by Gregory Cochran and Henry Harpending with whom most LWers are probably already familiar with) caught my eye:
People who grow up in a small town, or an old and stable neighborhood, often know their neighbors. More than than that, they know pretty much everything that’s happened for the past couple of generations, whether they want to or not. For many Americans, probably most, this isn’t the case. Mobility breeds anonymity. Suburban kids haven’t necessarily been hanging out with the same peers since kindergarten, and even if they have, they probably don’t much about their friends’ sibs and parents.
If you do have that thick local knowledge, significant trait heritability is fairly obvious. You notice that the valedictorians cluster in a few families, and you also know that those families don’t need to put their kids under high pressure to get those results. They’re just smart. Some are smart but too rebellious to play the game – and that runs in families too. For that matter, you know that those family similarities, although real and noticeable, are far from absolute. You see a lot of variation within a family.
If you don’t have it, it’s easier to believe that cognitive or personality traits are generated by environmental influences – how your family toilet trained you, whether they sent you to a prep school, etc. Easier to believe, but false.
So it isn’t all that difficult to teach quantitative genetics to someone with that background. They already know it, more or less. Possession of this kind of knowledge must have been the norm in the human past. I’m sure that Bushmen have it.
The loss of this knowledge must have significant consequences, not just susceptibility to nurturist dogma. In the typical ancestral situation, you knew a lot about the relatives of all potential mates. Today, you might meet someone in college and know nothing about her family history. In particular, you might not be aware that schizophrenia runs in her family. You can’t weigh what you don’t know. In modern circumstances, I suspect that the reproductive success of people with a fair-sized dose of alleles that predispose to schiz has gone up – with the net consequence that selection is less effective at eliminating such alleles. The modern welfare state has probably had more impact, though. In the days of old, kids were likely to die if a parent flaked out. Today that does not happen.
Seems quite coherent. It meshes well with findings that the more children parents have the less they subscribe to nurture, since they finally, possibly for the first time ever, get some hands on experience with the nurture (nurture as in stuff like upbringing not nurture as in lead paint) versus. nature issue. Note that today urban, educated, highly intelligent people are less likley to have children than possibly ever, how is this likley to effect intellectual fashions?
Perhaps somewhat related to this is also the transition in the past 150 years (the time frame depending on where exactly you live) from agricultural communities, that often raised livestock to urban living. What exactly "variation" and "heredity" might mean in a intuitive way thus comes another source short with no clear replacement.
Consider a separate possibility: competition and opportunity abounds in urban areas, placing additional value on intelligence and skill acquisition. Since there is nothing which can be done about intelligence, really, focusing on skill acquisition is a better strategy. Parents who believe very thoroughly in the nurture argument may be much more willing to invest heavily in their child's education, expecting far greater benefits than are actually possible. Because the perceived value of success is higher it succeeds more often in the face of discounting.
In this case, the false belief is highly adaptive socially, with people adhering to it acquiring better positions in society. While this does not really lend itself to much genetic replication, meme spread should accelerate. I think that, prima facie, we should prefer this explanation; because it does not rely on stories LessWrongians may find aggrandizing, it is less likely that we will be accepting this narrative through bias.
I agree.
The problem is that this is one out of uncountable equally plausible stories that, if true, explains a tiny effect on a meme's spread that varies in direction depending on the story. The effect of offspring's eventual financial success on this sort of child-raising meme's spread is negligible. Isolating it and finding the direction doesn't tell me about the important factors behind such memes.
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