    > Almost all human traits are partly genetic and partly due to the environment and/or random. If you could change the world and reduce the amount of randomness, then of course heritability would go up.

There has been a lot of effort to determine systematic environmental factors that would influence things like intelligence and while it's easy to do harm (lead exposure) it's all but impossible to do any good.

It implies that the only environment that matters is either purely random (truly random accidents, circumstances) or non-systematic (results from non-linear interaction of environment and genes).

When stated that way it almost feels like a tautology because this is what genes exist to do in the first place. To control the interactions of their vessel and environment to the maximum degree. And from the perspective of an individual gene, all the other genes are part of the environment too.

    > There is no such thing as “true” heritability, independent of the contingent facts of our world.

It's uncomputable (need to run Monte Carlo simulations on a human life). All efforts are to approximate it.

▲ somenameforme 20 hours ago | parent | next [-]

What you're saying is completely accurate, but I'd add that it's all relative. Are you falling towards the ground, or is the ground falling towards you? For instance malnutrition lowers IQ, in both directions. There is an inverse correlation between IQ and BMI, but what's most interesting is that that correlation has maintained just as strong even as obesity rates skyrocketed, which is suggestive that there's probably something causal, in some direction, somewhere in there.

And so in modern times if it turns out that eating less than most people apparently want to contributes to IQ, are you doing something good by eating less, or are they doing something bad by eating more? I think it's basically the same thing, just looked at in different ways.

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Earw0rm 19 hours ago | parent | next [-]

Or are smarter people better able to regulate their food intake? (Either innately, or because society gives them other privileges which makes them less likely to overeat)

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lo_zamoyski 19 hours ago | parent [-]

I would say, that on the whole, this has to do with habituated impulse control and self-restraint.

Classical writers speak of this as well, things like how inordinate and undisciplined appetites (not just for food, mind you; sex, too, and undue acquisitiveness of all sorts, for instance) darken the mind. What is inordinate and undisciplined is not proportioned or directed by reason. So, such character traits are rooted in fidelity to reason which means that not only do they avoid the aforementioned darkening of the mind by moderation of appetite, but the very character strength of being able to do so enables rational existence in other things.

Innate intelligence doesn't secure discipline. Indeed, it gives the person a bigger footgun and allows for more elaborate rationalizations of vice.

	▲	Earw0rm 14 hours ago \| parent [-]
		Which then begs the question, what is IQ actually measuring - something more like innate intelligence, or a fairly big slice of learned, habituated test-taking ability? Regardless of what underlying trait it's actually measuring, the habituation factory is a big component of its supposed bias - that is, has your background taught you the kind of problem-solving habits that will help you to post the best possible score?

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hirvi74 16 hours ago | parent | prev [-]

> which is suggestive that there's probably something causal, in some direction, somewhere in there.

Perhaps suggestive, but far from conclusive (I know you know this too). To me, it is suggestive that there is likely some other factor that may explain the relationship better, but then again, I am wrong more often than right, so what do I know? ;)

For example, compare that to growing wealth inequality, and I wouldn't be surprised if that is a potential factor. Less income = less access to care, less access to healthier food options, perhaps less time to for self-care, etc., and if wealth/career potential is gatekept by academic achievement, economic utility, or intelligence, then I can see the two, intelligence and BMI, being correlated, but not directly causal. Though, no study would give people large sums of money to improve their lives, so I doubt we will know for certain.

▲ LudwigNagasena 15 hours ago | parent | prev | next [-]

The point is not that it is something hard to compute that we can only approximate. The point is that there is no well-defined heritability independent of the environmental distribution.

	▲	red75prime an hour ago \| parent [-]
		There's no well defined "a rock too heavy for a person to lift" too, but we manage. So, what's the point?

▲ pron 18 hours ago | parent | prev | next [-]

> while it's easy to do harm (lead exposure) it's all but impossible to do any good.

That's just a meaningless statement no different from "while it's easy to subtract negative numbers, it's all but impossible to add positive numbers."

> or non-systematic (results from non-linear interaction of environment and genes).

Non-linear interaction does not mean non-systematic. Computer programs are fully deterministic (and therefore "systematic") while being non-linear (and therefore generally unpredictable). It is true to say that when things are non-linear it's hard to tell with certainty what effect some policy will have, but given that most human systems are non-linear, this is true for just about everything.

▲ bglazer 18 hours ago | parent | prev [-]

This is demonstrably untrue. IQ has increased consistently for decades, far faster than genetic factors can explain. Environmental factors like education, nutrition, and medical care are the obvious explanation.

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eikenberry 17 hours ago | parent | next [-]

This also assumes that IQ testing has remained static. It has not. IQ tests continue to evolve and there are >1 of them and they do not all agree. I.E. the tests themselves might be responsible for some of the variance.

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NooneAtAll3 18 hours ago | parent | prev | next [-]

how does one separate "doing good" and "stop doing harm"?

I'd personally count nutrition squarely in the second category

	▲	ZeroGravitas 5 hours ago \| parent \| next [-]
		The recent marathon world records are apparently due to improved nutrition. Here's the producer of the hydrogels talking about the exact process of getting the maximum carbohydrates into the runner: https://maurten.no/blogs/m-magazine/how-sabastian-sawe-fuele... > At the elite level, marathon performance is defined by energy availability as much as physiology. > Maintaining a pace of 2:50 per kilometer requires a constant supply of fuel. Even small disruptions in energy delivery can result in significant time loss.
	▲	nightpool 17 hours ago \| parent \| prev [-]
		coppsilgold is the one who made a hard-line, clear-cut dichotomy when they said "it's easy to do harm [but] it's all but impossible to do any good". bglazer referenced several interventions that are known to increase IQ which challenge this dichotomy. Saying that it is difficult to separate "doing good" and "stop doing harm" is agreeing with the point that coppsilgold created a distinction without a difference.

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whatever1 18 hours ago | parent | prev [-]

Also we are past that. Now IQ started decreasing.

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NooneAtAll3 18 hours ago | parent [-]

it's hard to separate IQ decreasing and return to mean with IQ stabilizing

in 20th century most of the world moved past famine and toxins - did any factor of similar scale happen in 21st century as well to start looking for opposite processes?

	▲	joenot443 a few seconds ago \| parent \| next [-]
		Generally that statistic refers to populations in isolation, not the entire world in aggregate. It is fairly well agreed upon that American kids across the nation are currently testing lower than they were in 2010.
	▲	PunchyHamster 17 hours ago \| parent \| prev [-]
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