Comment by cutemonster
5 hours ago
> > twin studies and they have taken in serious beating in the past decade, especially in light of GWAS.
Here's a twin study from 2015, newer than the books (Clean Slate etc) and papers you (David) mentioned.
"Thinking positively: The genetics of high intelligence" https://pmc.ncbi.nlm.nih.gov/articles/PMC4286575/
Figure 3 indicates that intelligence is pretty strongly inherited, and they arrive at 0.44.
Now you're saying that that doesn't matter because of GWAS? Sounds a bit hand-wavy to me.
> > Sasha Gusev's Substack as an entry point: https://theinfinitesimal.substack.com
Blog post looks biased. So there's a controversy: https://en.wikipedia.org/wiki/Missing_heritability_problem
And there's two camps:
https://www.clearerthinking.org/post/the-missing-heritabilit...
(I like that article!)
And the two of you (Davind and Thomas) seem to be in the "The DNA Proponents" camp. The other is "The Twin Study Advocates" camp.
I guess now I'm in "The middle ground" camp, no longer in the "Twin Study Advocates".
Thanks for that. Maybe I'll check back in 10 years later and see what has happened.
The "warring camps" framing is very overstated. Greenberg, who doesn't practice in this space, believes it to be a vital concern, but giants in the twin-study practitioner field freely cite GWAS results, including the EA studies.
A 2015 twin study result is basically a citation to the phlogiston era of polygenic population-wide genetic surveys. Heritability estimates of that vintage basically define away indirect genetic effects, which subsequent work appears to have very clearly established; the work now is on characterizing and bounding it, not asking whether it's real.
"Blog post looks biased" is not a good way to address this unless you actually practice in the space, like the author does, and are in conversation with other practitioners in the space, like the author is. You find lots of --- let's generally call them pop science writers --- knee-jerk responding to the new rounds of heritability numbers, but those same authors often wrote excitedly about how GWAS results would bolster their priors in the years before the results were published. It's worth paying attention to the backgrounds of the people writing about this stuff!
I substantially rewrote this comment, which was sprawling; the original is preserved here: https://gist.github.com/tqbf/b118ec9f9e69e0f3f61003c152d0d44...
Great to see you're making progress!
A few posts ago you were alluding to heritability in the 0.7-0.8 range, as a reason to dismiss the writings of Einstein, Newton, Descartes and Grothendieck.
Now you're at 0.44. If you discount for a mild EEA violation correction, you'd easily get to 0.3 or below — a figure which I personally find believable.
Just FYI, I don't belong to any "camp". These aren't camps but techniques and models. Intra-family GWAS provide underestimated lower bounds, twin studies provide wildly overestimated upper bounds. I don't care about the exact value, as long at it doesn't serve as a distraction from the (much more interesting!) story of how one can develop one's ability for mathematics.
In any case, IQ is a pretty boring construct, especially on the higher end where it's clearly uncalibrated. And it's a deep misunderstanding of mathematics to overestimate the role of "computational ability / short term memory / whatever" vs the particular psychological attitude and mental actions that are key to becoming better at math.
Now that the smoke screen has evaporated, can we please return to the main topic?