17 Comments
User's avatar
James Thompson's avatar

I was thinking of writing a summary of the main points, but perhaps you already have one?

Expand full comment
Gregory Connor's avatar

I had no plan for a summary of the main points; if you would like to attempt it that would be great. Seven lines of evidence (as in my essay) is a long list to recall, so last night I tried to find a useful mnemonic, along the lines of OCEAN or HOMES (to remember the names of the American Great Lakes). The best that I could come up with is SAMPLES: 1. Stability of observed test score gap(s), 2. Admixture regression findings, 3. Magnetic image resonance findings, 4. Paleogenetic findings (the measured increase in European intelligence polygenic risk scores over millenia, 5. Longitudinal analysis (worldwide comparisons of test scores), 6. Environmental impacts and their small size (too small to explain observed gaps), 7. Spearman's hypothesis. ...... I am not sure if that mnemonic works perhaps someone can do better than that.

Expand full comment
James Thompson's avatar

Very good memonic.

On the other hand, your actual sequence is very well thought out, because you begin on a strong and obvious point: the gap hasn't got any smaller.

I have done a very crude version last night, based on the following principles:

1 Most people don't read very much, nor very far into that little they read

2 Hence, very short points in short sentences (Flesch reading formula).

3 Use simple words whenever possible.

Can I send you the draft later today?

James

Expand full comment
Gregory Connor's avatar

Yes, please. I am away for most of the remainder of the day but will look at it in the morning, or anytime after then. No rush.

Expand full comment
James Thompson's avatar

Dear Gregory, you may find this a savage reduction of your fine essay, and the final section even more barbarbaric, and far too brief, but I am trying to get you in front of as many readers as possible.

Explanatory gaps in test score gaps

Gregory Conner has written a very good and detailed examination of intelligence differences between white and black Americans, showing that a purely environmental cause is unlikely to be true. Despite that, it is the standard and widely accepted view, in public at least.

It is worth reading.

https://www.aporiamagazine.com/p/facing-the-facts-about-test-score

In the hope of getting it an even wider readership, here is a very simplified summary of his arguments.

1: The intractable Black-white test score gap

Despite six decades of aggressive (and expensive) policy measures in the US to address the gap, a very substantial Black-white test score gap of 15 IQ points stubbornly remains, which is one standard deviation, and very big in practical terms. The evidence for this intractable gap is very strong.

2: Comparisons of average cognitive ability between nations

The international data on intelligence shows a uniform, worldwide underperformance of all predominantly African populations when compared to predominantly European or East Asian populations, despite different histories of slavery and colonialism. Only 6% of sub-Saharan African youths have the basic academic skills necessary to be internationally competitive in the modern global economy, compared to 72% in Europe, 76% in North America, and 71% in East Asia and the Pacific.

3: Spearman’s Hypothesis

The environment-only theory implies that the test score gap will be larger for intelligence test questions which are more susceptible to environmental influences. In fact, the gap is larger for intelligence test questions more strongly linked to genetic influences and smaller for test questions more strongly linked to environmental influences. For example, digits forwards is weakly related to general intelligence, while the harder digits-backwards task is more related to intelligence, and shows more race differences. It is not a cultural difference, since digits are used in both tests, it is a difference in intrinsic mental demands.

4: The low power of shared environment in explaining cognitive ability

The environment-only theory says that it is bad environments which lead to poor test scores in different races. How much of the difference within any group can be explained by bad environments? In fact, not all that much unless they are very, very bad environments. Since shared environments don’t explain much of the difference between people, the environmental differences between blacks and whites will need to be extraordinarily large to explain the size of the intelligence gap, and those profound differences are no longer found in the US.

Also, the gaps should be biggest when siblings are living together in the same (disadvantaged) family, and reduce when adults go on to build their own better environments, but in fact they hold steady throughout the entire life span.

5: Admixture

This one is very simple, and also very powerful. If intelligence gaps are due to how other groups treat you, then your social identity (the race you classify yourself as) will be more powerful than your genetics. In fact, it is the other way round. The “added together mixture of your genetic races” will be the stronger predictor of your life outcomes. For example, “an individual who has 60% African and 40% European ancestry will have a 60%-40% expected weighting of the cognitive-ability related genetic variants from these two populations. This leads naturally to a simple linear relationship between individuals’ ancestry proportions and their expected cognitive abilities.

“Admixture regression analysis has been used over the last two decades by genetic epidemiologists to study race and ethnicity related differences in alcohol dependence, height, asthma risk, cardiovascular disease, sleep depth, cigarette smoking behavior, metabolomics, cancer, and diabetes.” It also works for intelligence.

6: Brain size differences across biogeographic ancestries

The evidence finds substantial differences, with on average larger brains among individuals with higher proportions of European versus African ancestry.

Individuals with African ancestry have average cranial volume 6% below those with European ancestry, whereas individuals with East Asian ancestry have average cranial volume 1.3% higher.

7: New findings on the recent evolution of intelligence-related genetic variation

Recent genetic research shows that genes associated with higher intelligence (polygenic risk scores) have increased substantially in the European population over the last ten thousand years. Parallel evolution in other regions could have similar effects after the African dispersal of humans to multiple continents, but the impact on average intelligence of any evolution in other continents is unlikely to be exactly the same worldwide. In fact, the intelligence-related average polygenic risk score for academic achievement of people who identify as Black is significantly lower than that of people who identify as White. This finding is suggestive, but must be considered tentative, since not enough Black individuals have been studied. Alarmingly, access to the available data on race differences is being restricted, and publication of results hampered.

In conclusion, the “environment only” explanation is very weak. The “genetics and environment” explanation is stronger. It explains things seamlessly using fact-finding methods from different tests and different countries, which supports a cohesive theoretical structure. The “environment only” theory relies on a patchwork of explanations to counter each separate line of empirical evidence against it. This is important: even if each of the seven counter-arguments sound plausible, Occam’s Razor leads us to give more weight to the simpler argument: that there is a genetic component to racial differences in intelligence. Privately, the majority of researchers believe there is a genetic component of at least 20%; and half of them think the component is as high as 50%.

Why don’t people admit this in public? Probably because they fear the findings would increase racial hostility against Blacks, which might be the case. Individual differences in ability are generally seen in a kinder light, but group differences might not be accepted so compassionately.

In sum, the public position is to promulgate a Noble Lie, without allowing an open discussion of the costs of such dishonesty.

Expand full comment
Gregory Connor's avatar

Thanks so much, this is wonderful. I sent a list of minor suggested edits via your substack-provided email.

Expand full comment
James Thompson's avatar

Excellent account, for which many thanks.

Expand full comment
Rethinker's avatar

This otherwise excellent article neglects to mention that the most harmful result of suppressing the truth about genetically caused racial variation in intelligence, is that the media and intellectuals and even organs of government have been forced for decades to demonize and demoralize White people as the cause of unequal racial outcomes in income and education. This certainly must be at least as important an ethical consideration as the effect that not suppressing the environmental lie might have on blacks. Refusal to acknowledge innate racial differences in intelligence has led to a disastrous system of anti-White racial oppression in South Africa, and it is gradually doing the same in the USA. There is really nothing wrong with a system of voluntary segregation and integration, if this is what most people of all races want anyway. And it probably is.

For example, Derek Bell, a cofounder of critical race theory, urged African-Americans to stop struggling for integration and start building quality segregated black schools. And some public schools in the USA are now giving blacks and Hispanics the option to have separate racially segregated classes.

https://m.youtube.com/watch?v=Mk6PnDmBdqQ&t=1479s&pp=ygUOVHJpZ2dlcm5vbWV0cnk%3D

Expand full comment
James Thompson's avatar

can you please send to thompsonbain at gmail.com ?

Expand full comment
James Thompson's avatar

can you tell me which email? I can't find anything at the moment

James

Expand full comment
Realist's avatar

Thanks for another informative article on cognitive differences between races. I did notice the author has a habit of using upper case (B)lack and lower case (w)hite. I am curious about the reason for this.

A rational person will seek the truth and let the chips fall where they may. Hiding from reality is not a viable solution to a problem.

Not only are race differences not totally environmental, but the differences are most likely around eighty percent genetic.

Expand full comment
Gregory Connor's avatar

Thanks for the comment. A few people to whom I sent the essay had the same objection. The capitalization convention varies, which provides the writer with some flexibility. My own perspective is that in an essay which has some empirical facts which could be misinterpreted as demeaning to Blacks it was nice to show an extra attempt at respectfulness. It was an attempt at showing care and respect. I accept that some readers find it jarring, due to the asymmetry.

Expand full comment
Realist's avatar

"It was an attempt at showing care and respect."

It would be nice if you would show some care and respect toward Whites by using upper case W when you use upper case B.

Expand full comment
User's avatar
Comment deleted
Dec 14, 2023
Comment deleted
Expand full comment
Gregory Connor's avatar

I am very glad that you liked the essay.

In response to your first question, it is not possible to have a good-faith argument with an environmentalist regarding genetic causes of test cause gaps. They would lose any good-faith argument and all of the intellectually competent ones know this, so they do not engage in such arguments. It is a shame. Cofnas has written about this; I mention his paper in the essay and you can find the reference.

To understand the portability of polygenic scores across races you need to come to grips with linkage disequilibrium. Suppose that I had a 10-million deck of numbered cards which were ordered from one to ten million. I shuffled it very slightly by “cutting” the deck randomly in 20 places and putting the cut sections of the deck back together in a random order. With ten million cards and only 20 “cuts” of the deck this would be an extremely inadequate shuffle! If I chose any card in the deck, the card next to it would be in numerical order with probability close to one. Even if I repeat this rough “shuffling” process hundreds of times, big sections of the deck will still be in numerical order. That is what happens with genetic variation between generations. A child’s DNA is an (approx.) twenty-section combination of his two parents’ DNA. Hence the vast majority of neighborhoods in the child’s genome are preserved intact from one or the other of the two parents. This non-randomness is preserved for hundreds of generations. That is called linkage disequilibrium. Polygenic risk indices rely on linkage disequilibrium since they do not get the exact genetic variant that causally relates to the trait, only a genetic variant in the neighborhood of the causally related one.

Expand full comment
User's avatar
Comment deleted
Dec 15, 2023
Comment deleted
Expand full comment
Gregory Connor's avatar

Q: Is it that the "decks" across racial groups are too different?

A: Yes

Emil Kirkegaard wrote a careful response to Bird. https://emilkirkegaard.dk/en/2022/01/the-bird-paper-and-hereditarian-predictions/

There is nothing of substance in Bird's paper, despite the technical verbosity. The objective of Bird's paper is to find some shred of evidence in favor of the pure-envrionmentalist theory, no matter how tortuous the argument.

Bird is an aggressive left-wing political activist and not willing to take a balanced perspective on the evidence. He led the campaign at Michigan State University to get Stephen Hsu fired. He also was involved in the cancellation attacks on Colin Wright. See https://www.realityslaststand.com/p/think-cancel-culture-doesnt-exist

Good-faith arguments do not involve driving opposing views off campus using vitriolic political campaigns. Take him off your list of good-faith arguments.

Expand full comment
User's avatar
Comment deleted
Dec 16, 2023Edited
Comment deleted
Expand full comment
Gregory Connor's avatar

It turns out empirically that polygenic indices for intelligence are reasonably portable across ancestries despite some distortions due to differences in linkage disequilibrium. For some other traits, e.g. height, the distortion of polygenic index scores across ancestries is much worse.

Expand full comment