[Causality1]

Frankly I think we're quite lucky we're not a more diverse species. There's no biological reason a human subspecies couldn't have gotten isolated in a valley somewhere and ended up being fifty IQ points smarter or dumber than the rest of humanity. Same goes for our sexes being identically intellectually capable. Would the principle of egalitarianism have ever emerged in such a world?

[AnthonyMouse]

> There's no biological reason a human subspecies couldn't have gotten isolated in a valley somewhere and ended up being fifty IQ points smarter or dumber than the rest of humanity. Same goes for our sexes being identically intellectually capable. Would the principle of egalitarianism have ever emerged in such a world?

I want to say yes, because how are you even distinguishing that world from this one? There exist humans who are fifty IQ points smarter or dumber than other humans who also exist.

The batshit crazy idea is that these differences are caused by or intrinsically bound with skin color.

As for sex differences, here's the money quote:

https://en.wikipedia.org/wiki/Sex_differences_in_intelligenc...

> All or most of the major tests commonly used to measure intelligence have been constructed so that there are no overall score differences between males and females.

We believe in egalitarianism, therefore IQ tests that show a sex difference are wrong, therefore we use IQ tests that show no sex difference.

Now, if there are biological differences between the sexes, they could not only go either way, they could go both ways. It's possible that on average women are better at X and men are better at Y, so you could really design a test to show whatever result you want.

It's also obviously the case that no matter what the averages are, the world's highest-scoring male will almost certainly have a better score than the world's lowest-scoring female and vice versa. So arguments of the form "women can't do X" are stupid even if you can find a statistically significant difference in the averages using some metric. Because most people are not exactly average.

Discrimination is the assumption that all members of a group are the same.

[Causality1]

There exist humans who are fifty IQ points smarter or dumber than other humans who also exist.

Sure but they're not all in the same ethnic group. What if a populous group had the peak of their intellectual curve far down the range? If, say, Gauls/French people were almost entirely simpletons equivalent to someone with Down Syndrome? Would they be enslaved and turned into a worldwide servant class? Every other group that were thought of as being inferior can be demonstrably equal to their oppressors but I think a world in which they weren't could be very different.

[mr_toad]

> What if a populous group had the peak of their intellectual curve far down the range?

It takes a long time, an evolutionary timescale for that sort of difference to emerge. There’s an argument that the reason that modern humans are so homogeneous is because we wiped out all competition long before we had recorded history or civilisation.

[haihaibye]

That's not a hypothetical, many Pygmies are currently enslaved

https://mankindquarterly.org/archive/issue/51-4/2

[rebuilder]

The thing is, when humans conquer a rival group, we tend to rape the survivors. That kind of ensures genetic mixing, so this kind large discrepancy in innate ability couldn't really appear.

[avgcorrection]

We wouldn’t want a world where IQ fetishists were to be even more discriminatory against people with lower IQs. (Or supposedly lower IQs.) It’s bad enough as things currently stand.

[foobiekr]

What if it cured cancer and HIV?

[avgcorrection]

No.

[technobabbler]

There's also no biological reason 8 billion individual hominids evolved under different conditions and upbringing and nutrition should share the same intellectual capacity, any more than all 8 billion would be equally good sprinters or have the same skin tone or oxygen capacity.

The brain is just another blob of flesh, and what we understand of its capacities suggest it's at least partially inheritable. You'd have to ignore a lot of evidence to believe that all humans are intellectually equal. If there is variation and there is mutation and there are different pockets of populations, there are going to be evolutionary differences between them. Then in terms of sexual selection, we'd have to believe that intelligence as a criterion for mate selection is equally important across cultures, and also impacts offspring fitness the same across all cultures and environments -- vs, say, disease or sun resistance in the tropics. Otherwise, differences would naturally arise over time.

The tricky part is coming up a way to define, much less measure, "intellectual capacity" across different cultures and ways of knowing. IQ tests are pretty biased and arguably a useless measure of evolutionary fitness in many human cultures. Even if you could create the perfect cross-cultural IQ definition and test, administering and collecting such a thing would be nearly impossible in a world where many countries don't even have proper birth records or thorough population censuses (even a basic count, without in-depth testing).

We already know that, within the upper and lower bounds, there can be great variations of "intelligence" WITHIN populations group, as well as smaller differences between them. But we lack the methodology and cultural transparency to be able to accurately measure whether the cross-cultural error bars fall within the intracultural ones. That's not for lack of trying, mind you... many careers have either risen to infamy or else have been destroyed for daring to suggest such things.

In other words, it's not that all humans are equal, it's that we're SO diverse it's hard to group us into neat little groups, whether by race, ancestry, skin color, intelligence, or any other genetic factor. Because the underlying genes themselves don't work that way. They're always changing and competing.

The principles of egalitarianism are a cultural ideal (not shared by much of the world, mind you), not necessarily scientific observations. The scientific input to the ideal, if anything, is not that "the are no differences between groups" but "there are so many differences that these groupings don't really make sense; there are a million other equally valid groupings".