I'm not a blank-slateist or an anti-hereditarian, as someone else claimed earlier today. I understand that cognitive disabilities are often causally --- mechanistically understood --- genetic.

But leaving aside things like Trisomy 21, your evidence here is twin study heritability. Heritability is not genetic determinism; it's almost a category error to claim otherwise, since "heritability" is really just a way of framing the question of whether something is genetically determined --- you still have to answer the question! There's a whole big research field controversy about this, "missing heritability", exploring (in part) why molecular genetics results, especially when corrected for things like within-family bias, are returning such lower heritability estimates than classic twin studies.

I do not believe that any random child selected at birth has an equivalent potential to win a Fields Medal, given the optimal environment to do that in. But the "hard truth nobody wants to face", from the parent commenter, is subtextually about race --- and there the evidence is a wreck; extraordinarily unlikely to bear any fruit.

> and there the evidence is a wreck; extraordinarily unlikely to bear any fruit

Is there any new reading here? I used to follow this stuff much more closely a decade ago, but came to the conclusion most scientists will go to great lengths to avoid saying some races (if they don’t barrage you with pedantry regarding what race is) are on average different in some axis than others. There were a few out there who were able to say the politically incorrect thing only because objective science was strongly in their favor, but they still had the full force of the consensus academia coming down on them.

I lost interest when, much like history, it became obvious the field was too political for any real truth to be found. Maybe in 100 years or so.