Charles Murray doesn’t put it this way, but he’s trying to save America (if not the entire Western liberal order). Everything we’re allowed to say about race, sex, & class is wrong, & everybody knows it. The systems built around the post-1960s progressive consensus have failed, & are now collapsing under the weight of their own contradictions - but the mechanisms that enforce that consensus are stronger than ever. So with
> A higher-IQ farmer is meaningfully better at farming. As well as more honest & prosocial & mentally stable & tall & handsome. If it’s The universal adaptation, with no drawbacks, why aren’t we smarter?
I've seen it suggested that IQ (and height and general health) are downstream (to at least some degree) of a kind of general factor of genetic health ("mutational load" is one term that comes up here). The idea is that external impositions almost always cause net damage, so some people are just closer to "the ideal human" and these people have better outcomes in just about every sphere, just because of having fewer mutations or whatever.
The question of why this genotype isn't more universally dominant is interesting. One factor going into it may be exposure to external mutagens, but it's not clear how much this varies over times and places. Another is that the "higher-quality" genomes may or may not confer an actual selective advantage -- much discussed in this conversation is the "IQ shredder" phenomenon, where economically successful areas have below-replacement birthrates and end up sucking the most successful subsets of surrounding (poorer, more fertile) areas in and causing them to have fewer children. It seems that in modern times male IQ has been a net fertility benefit, but female IQ has been a net detriment, presumably due to smarter women having greater success in education/career/etc and thus prioritizing it over family. But I don't know if there's any way to quantify the magnitude of this effect over generations.
> Murray’s argument that nurture is irrelevant to child outcomes is pretty weird given the enormous volume of nurturing that humans instinctively do, & the extent to which they’re rewarded - socially & neurochemically - for doing it. Virtually all parents, in all societies, do a lot more than just “keep your kids alive & don’t horrifically abuse them” - which Murray seems to think is all that can be done about child outcomes.
I think this is basically the result of over-interpreting twin studies. The modal twin study is not actually a study of identical twins raised apart -- this circumstance is too rare to get a lot of data on. Rather, it's a comparison of pairs of identical twins (raised together) and fraternal twins (raised together). The idea is that, to the degree that identical twins are more similar than fraternal twins, this must be the influence of genes over environment. But this mechanism is obviously not capable of isolating the real effects of nurture/environment, because almost all pairs of children raised in separate households are also born of different parents. And adoption studies are 1. much rarer and 2. may well come with inherent confounders, as you note.
> A higher-IQ farmer is meaningfully better at farming. As well as more honest & prosocial & mentally stable & tall & handsome. If it’s The universal adaptation, with no drawbacks, why aren’t we smarter?
I've seen it suggested that IQ (and height and general health) are downstream (to at least some degree) of a kind of general factor of genetic health ("mutational load" is one term that comes up here). The idea is that external impositions almost always cause net damage, so some people are just closer to "the ideal human" and these people have better outcomes in just about every sphere, just because of having fewer mutations or whatever.
The question of why this genotype isn't more universally dominant is interesting. One factor going into it may be exposure to external mutagens, but it's not clear how much this varies over times and places. Another is that the "higher-quality" genomes may or may not confer an actual selective advantage -- much discussed in this conversation is the "IQ shredder" phenomenon, where economically successful areas have below-replacement birthrates and end up sucking the most successful subsets of surrounding (poorer, more fertile) areas in and causing them to have fewer children. It seems that in modern times male IQ has been a net fertility benefit, but female IQ has been a net detriment, presumably due to smarter women having greater success in education/career/etc and thus prioritizing it over family. But I don't know if there's any way to quantify the magnitude of this effect over generations.
> Murray’s argument that nurture is irrelevant to child outcomes is pretty weird given the enormous volume of nurturing that humans instinctively do, & the extent to which they’re rewarded - socially & neurochemically - for doing it. Virtually all parents, in all societies, do a lot more than just “keep your kids alive & don’t horrifically abuse them” - which Murray seems to think is all that can be done about child outcomes.
I think this is basically the result of over-interpreting twin studies. The modal twin study is not actually a study of identical twins raised apart -- this circumstance is too rare to get a lot of data on. Rather, it's a comparison of pairs of identical twins (raised together) and fraternal twins (raised together). The idea is that, to the degree that identical twins are more similar than fraternal twins, this must be the influence of genes over environment. But this mechanism is obviously not capable of isolating the real effects of nurture/environment, because almost all pairs of children raised in separate households are also born of different parents. And adoption studies are 1. much rarer and 2. may well come with inherent confounders, as you note.