Interesting that there's no mention of human biodiversity (aka blacks are dumb), as if you spend five minutes on #lesswrong you'll notice that that's a big issue for gwern and the other goons.
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Thing is: Are you absolutely sure that notion of human biodiversity is wrong? IQ is heritable, as height is heritable. You'll grant that there are populations that differ in their genetic potential for height -- e.g. Dalmatians vs. Pygmies -- so how is it that you dismiss out of hand the notion that there might be population-wide differences in the genetic potential for intelligence?
I can hear it now: "But IQ is not intelligence!" I agree to a point, but IQ -- and, strangely, verbal IQ in particular -- maps very neatly to one's potential for achievement in all scientific and technological fields.
The Truth is a jealous goddess: If you devote yourself to her, you must do so entirely, and take the bad along with the good. You don't get to decide what's out of bounds; no field of inquiry should be off-limits.
> https://extension.missouri.edu/publications/g2910
Heritability is simply a measure of how much of the variation in a trait, like height or IQ, is due to genetic factors rather than environmental influences in a given population. Could be feedlot steers, could be broiler chickens, could be humans. In humans, traits like height are very highly heritable, at ~0.8. Certain others, like eye color, are heritable to ~0.98.
Differences in IQ between groups are apparently far more modest, but, however distasteful, it's still possible to speak of them, and it's possible to make statistical statements about them. My position is simply that, on the one side, it should be done in good faith -- and, on the other side, it shouldn't be seen as something heretical.
That aside, we're getting into semantics. Whether you call it "genetic determinism" or "heritability," we're talking about durable group differences in genetically-mediated traits. And that is what people may find distasteful or even heretical.
The semantics matter, because the evidence supporting HBD positions is stated in terms of the technical definition of heritability.
While I've got you, can I ask that you stop evoking "heresy" and "distaste" in this thread? I believe I'm making simple, objective points, not summoning opprobrium on your position.
But traits like IQ, height, and eye color are both (A) highly heritable and (B) substantially shaped by genetic factors. In casual online discourse, I believe that (B) is usually taken for granted, so it's glossed over, and when people say that any given trait is "heritable" they're also assuming that (B) is true for the trait. At least, I am guilty of that lapse.
And I take your point about language.
There is growing evidence that group IQ heritability isn't evidence of genetic causation.
First sentence of the conclusion: "Genetic association studies have confirmed a century of quantitative genetic research showing that inherited DNA differences are responsible for substantial individual differences in intelligence test scores."
Related: https://www.pnas.org/doi/full/10.1073/pnas.1408777111
The trouble is that, like height, IQ is governed by a vast network of "genes of small effect," so a comprehensive view has proven difficult to nail down. Progress is apparently being made, though slowly.
> There is growing evidence that group IQ heritability isn't evidence of genetic causation.
What evidence do you speak of?
An example of evidence against the reliability of educational attainment and intelligence heritability statistics: comparing intra-family heritability (across large numbers of families) to population-wide studies: for educational attainment, it turns out there's little correlation between the two; for simpler phenotypical traits, there's almost 100% correlation.
To sum this up:
1. The 2018 Plomin study gives sharply lower genetic/EA numbers than were floating around previously (say, from the Jensen-ist era)
2. Plomin's own numbers were preliminary and overstated
3. Researchers in the field criticized that study nonetheless
4. Subsequent studies on direct heritability and molecular heritability put even lower ceilings on it (basically, all credible behavioral trait heritability work has been done after 2018 --- and in fact this is broadly true of a lot of genetics work, not just trying to statistically mine behavioral traits out of genome scoring)
5. Even those results have flunked basic sanity tests (for instance, getting wildly different results in intra-family vs population-wide studies).
It's not looking good for people fixated on this idea.
† I'm being very loosy-goosey with the numbers and units here
We might want to look at the fundamentals: How is IQ qualitatively different from height, eye color, schizophrenia -- or any other highly complex, heritable polygenic trait? (One could also extend this to the many traits that animal breeders keep an eye on.) None of them have been fully pinned-down yet, but I don't believe that they can't be fully described in principle.
It's true that GWAS for intelligence explains <5% of variance today, but GWAS for height was in the same position a decade ago. Today polygenic scores for height predict over 40% of variance.
All this happens before we even reach questions about test-test reliability of IQ, or of whether gene-environmental interactions are uniform between Europe and other population cohorts (they do not appear to be!). It defines away SES confounding (which appears to be a significant issue). It has thus far largely ignored epigenetics. And, of course, for it to mean anything, the hypothesis also has to defend the idea that IQ/EA, at least in its genetic component, is immutable.
All that aside, I'm mostly just here to say that simple heritability statistics don't say what people on HN seem to think they say.