[quantumofmalice]

The consensus amongst intelligence researchers is that adult intelligence is ~70-80% based on genetic factors. I refer you to The Neuroscience of Intelligence - Cambridge Fundamentals of Neuroscience in Psychology by Richard Haier and the many studies sited therein.

We should help poor and less intelligent people for moral reasons, but it is unlikely to improve intelligence in the poorer population and, if the aid is structured dysgenically, it will serve only to compound the problem.

[hwillis]

That's incorrect; heritability is not reflective of environmental factors. The classic example is height: height is ~80% heritable, but has been increasing steadily for centuries due to environment.

Heritability only applies to the population studied, so unless you specifically look at poor vs wealthy people you don't see the impact of the environment. If you do that, up to 50% of the variance in IQ can be described by environmental factors[1]. This study[2] says: "Among lower income families, the proportions were in the reverse direction, 39% genetic and 45% shared environment." This one[3] says: " The models suggest that in impoverished families, 60% of the variance in IQ is accounted for by the shared environment, and the contribution of genes is close to zero; in affluent families, the result is almost exactly the reverse."

On top of that IQ and cultural influences are highly correlated[4].

> We should help poor and less intelligent people for moral reasons, but it is unlikely to improve intelligence in the poorer population and, if the aid is structured dysgenically, it will serve only to compound the problem.

Completely false- this study[5] found that for one group of adopted children averaged 19.5 IQ points higher when placed with wealthier families, compared to poorer families.

[1]: http://psycnet.apa.org/doiLanding?doi=10.1037%2F0033-2909.12...

[2]: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2903846/

[3]: https://www.ncbi.nlm.nih.gov/pubmed/14629696

[4]: https://blogs.scientificamerican.com/beautiful-minds/the-her...

[5]: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC17595/

[klmr]

As you are saying, 20–30 per cent of the variability of intelligence is not heritable. In other words, it’s acquired. This contradicts your claim that “[helping them] is unlikely to improve intelligence in the poorer population”. If done correctly, it will improve intelligence.

[quantumofmalice]

I am saying that the evidence suggests that 70-80% of adult[1] intelligence is based on genetic factors (that is distinct from heritability, which is lower, ~60% iirc) leaving the remaining 20-30% as unknown environmental factors. Wealth intuitively does play a role in that, although I believe (with as strong of evidence any anyone else does in the matter of environmental outcomes) that a strong parental bond matters more than wealth.

Again, my concern is that if unstructured wealth transfer is treated as a panacea, it will end up having compounding dysgenic effects that outweigh whatever short term individual benefits come of it. This will, in the not very long run, make poverty worse.

It isn't saving me any karma since people can't be rational about this topic, but I'll stress again that I think we should help the poor for moral reasons.

[1] - It is important to specify adult intelligence, because interventions do appear to help childhood IQ, but this effect fades into adulthood and eventual life outcomes. This is why there was a lot of excitement around Head Start initially, but it has failed to produce the large changes in society that was hoped for.

[klmr]

> genetic factors (that is distinct from heritability, which is lower, ~60%

You’re confusing something. Genetic factors = heritability, by definition[^1]. The 60% number is simply the heritability at birth (actually it’s probably lower), whereas the 80% number is the heritability in adults.

I see how this may sound confusing (how can heritability change?!). The reason is simply that “heritability of X” is, strictly speaking, a shortcut for “heritability in the variability of X”. As children grow up, they are influenced by their environment, which accounts for part of their intellectual development. As adults, they are still influenced by their environment but since the majority of their intellectual development has already taken place, there’s less room for variation here.

In other words, between two toddlers there’s a lot room for variation in upbringing with influence on their IQ. But if you take two University graduates from the same school, with doctoral degrees in particle physics, they will have relatively little variability in their IQ that’s due to their upbringing. Instead, the difference in their respective IQs will be mostly due to genetics (80% of it).

> but [the effect of intervention] fades into adulthood and eventual life outcomes

No, that’s another misinterpretation. The effect does not fade, it’s sustained. It simply seems to fade since you are comparing a different population/peer group (see my example of the two PhDs above).

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[^1] I’m aware that there are other vague definitions of heritability and genetic factors flying around, just to confuse things. However, these aren’t rigorously defined. In genetics, heritability = genetic factors.

[heurist]

The remaining 20-30% is related to childhood nutrition, education, opportunities to play, learning from peer groups... all of which are heavily impacted by wealth/poverty. And 20-30% is A LOT. Luck plays as much of a role in wealth as intelligence, so to assume that wealthy are more intelligent from genetic reasons and therefore poor families will remain poor is myopic.

Unstructured wealth transfer will never happen (except in cryptocurrencies) so I don't think you need to worry about that. The current effort is to get hardheaded free-marketers to recognize that equal opportunity is a myth.

[klmr]

> Unstructured wealth transfer will never happen

Basic income is arguably that, and there’s some hope that it will happen in the not so far future (or rather, there’s a reasonable fear that without it, and with the structural changes to the job market due to advanced automation, we’d be f#cked).