Saturday, June 07, 2014

Does The American Black/White IQ Gap Refute Human Equality?

For someone who is willing to risk provoking hostile reactions to his defense of the reality of race and the importance of racial differences, it is surprising that Nicholas Wade passes over the most emotionally charged racial topic--the American black/white IQ gap--in only a page and a half, and then concludes: "That issue needn't be resolved here" (A Troublesome Inheritance, 189-91).

This issue has deep moral and political implications.  If we conclude that some human racial groups are on average more intelligent than others because of their evolved genetic nature, does that deny the moral and political principle of equality of rights?  Or can we affirm the equal dignity of all human beings as a moral and political principle that has nothing to do with the scientific question of whether human beings are in fact equal or unequal in their genetic nature, and particularly in the genetics of intelligence?  Or does our belief in equal human dignity require a belief in the genetic equality of human beings in their cognitive capacities?

As I have indicated in a previous post, Wade is confusing, if not contradictory, in his answer to these questions.  On the one hand, he says that because of the fact/value dichotomy, there is no connection at all between scientific facts and moral values, and so we can affirm that racism is wrong "as a matter of principle, not science" (7).  On the other hand, he argues that "people being so similar, no one has the right or reason to assert superiority over a person of a different race," which seems to ground a moral claim on the scientific fact of human similarity (9).

There should be general agreement on the fact of racial differences in IQ scores in the United States.  Asian Americans score on average 105, European Americans score 100, and African Americans score 85 to 90.  There also should be general agreement that IQ arises both from genetic causes and from environmental causes.  But as is so often the case in nature/nurture issues, some people stress the genetic side, and others stress the environmental side.  The disagreement comes in explaining the causes of the IQ gap between African Americans and others--with hereditarians saying that the cause is mostly genetic and environmentalists saying it's mostly environmental.  If it's mostly genetic, the IQ gap cannot be closed anytime soon, and social policies to do this--such as special educational programs for black children--probably won't work.  If it's mostly environmental, the gap might be closed by social policies that change the environment for black children in ways that make it more conducive to cognitive development.

In principle, we should be able to resolve this debate by looking at the evidence.  But so far, the evidence is indecisive.  There are two reasons for this.  The first is that the shaping of intelligence through the interaction of genes, brains, individual differences, and social environment is so complex that it is extremely hard to study; and, as Wade repeatedly emphasizes, we simply don't know much about the precise mechanisms by which genes and environment influence intelligence and social behavior.

The second reason why this debate has not yet been resolved is that few academic researchers are willing to study this issue, because it has become taboo to discuss it.  Few universities even have courses on the scientific study of intelligence, because professors are afraid to teach such courses for fear that they will be branded as racists.  I must admit that I am one of those.  For many years, I have wanted to teach a course on the IQ debate.  But I have not, because I cannot imagine how I could do it without being accused of racism.

James Flynn is one of the leading academic researchers studying IQ and intelligence, and he argues for the environmentalist position--against hereditarians like Arthur Jensen and Charles Murray.  But Flynn chides his academic colleagues for refusing to engage in the research necessary to clarify this debate.  He identifies himself as a Social Democrat or Democratic Socialist, and so he's a man of the left.  But he accuses his leftist colleagues of suppressing all free inquiry into the causes of the black/white IQ gap, because they secretly suspect that the gap is genetic rather than environmental, and they fear that this would refute their belief in human equality.  Even if the black/white IQ gap turns out to be purely environmental, because it's a product of a black subculture that does not develop the skills for solving cognitively complex problems, which is Flynn's position--even this environmentalist explanation would be condemned by the left as racist stereotyping.

I admire Flynn because he openly admits that any conclusions about how to explain the racial IQ gap must be tentative, because the evidence so far is indecisive.  And, therefore, anyone who claims that this debate has been clearly decided has not seriously thought through the issue.  For this reason, he respects those like Jensen and Murray who disagree with him in a fair-minded way.  He has even dedicated his book Are We Getting Smarter? "To Arthur Jensen, Whose integrity never failed."  And while he has vigorously disagreed with the argument of Richard Herrnstein and Charles Murray's The Bell Curve, he insists that any serious thinker about this debate must respect the intellectual weight of that book.

I also admire Flynn because despite this uncertainty, he's willing to make the most plausible case he can for his position that the black/white IQ gap is mostly environmental rather than genetic.  He makes such a good argument that I am now leaning in his direction.

The best summary of his argument that I have seen is in his book Where Have All the Liberals Gone? Race, Class, and Ideals in America (Cambridge University Press, 2008), pages 68-111.  (A good overview of the science of intelligence and intelligence testing is Ian J. Deary's Intelligence: A Very Short Introduction [Oxford University Press, 2001].)

Flynn's conclusion is that black and white Americans are equal at conception in their genetic propensity for IQ, and therefore the entire black-white IQ gap is environmental; and the most important environmental cause is that the American black subculture from infancy to adulthood is less cognitively demanding than is the American white subculture.

He offers five lines of evidence and reasoning for this conclusion.  First, Flynn stresses the importance of a study by Klaus Eyferth of German children born after World War II whose mothers were German and fathers were American servicemen.  He compared 170 children whose fathers were black, and 69 whose fathers were white.  He matched the groups so that the social economic status of the mothers was similar.  The half-black and white children were almost equal in IQ and in their scoring for "general intelligence" (g) or GQ.  The tendency of a wide variety of cognitive skills to intercorrelate is measured as g, which many researchers regard as the cognitive complexity that is best identified with intelligence.  In America, black children tend to score lower in both IQ and GQ.  In Germany, it seems, this gap disappears.  Flynn's explanation is that when black genes are transmitted through white German women, the children become Germans with darker skins than other Germans; and although they might suffer some discriminatory treatment, they grow up without the black subculture of America.

It is possible that the black American soldiers in Europe were a more elite group than the white soldiers, if the low-IQ blacks were eliminated.  But if the racial IQ gap in America were genetic, we would expect that eliminating low-IQ blacks would reduce but not obliterate the gap.  That the gap in both IQ and GQ seen in America disappeared completely in Germany suggests that the American gap is not genetic but environmental, because it's created by the American environment of black subculture.

The problem, however, is that this is only one study involving a small number of cases; and so it's weighty but not conclusive.

Flynn's second line of argument is that studies of American black subculture have identified factors that make that subculture less cognitively complex than the American white subculture.  Flynn sees a succession of environments from birth to childhood to adulthood that impede the cognitive development of black Americans.  Black mothers tend to talk less and use smaller vocabularies around their infants than do white mothers.  Black children are more likely to hear commands and criticisms rather than encouraging praise from their mothers than are white children.  When mothers are helping their children with a cognitive test, black mothers tend to simply give the answers to their children, while white mothers ask questions or suggest strategies for the children to find the answers for themselves.

Elsie Moore compared two groups of adopted black children, 23 adopted by white middle-class families and 23 adopted by black middle-class families.  The adoptive mothers and fathers were similar in their years of schooling.  When the children were tested at ages 7 to 10, the black children adopted into the black families had an average IQ of 103.6, while those adopted into the white families had an average IQ of 117.1.  When Moore studied how the mothers interacted with their children while they were being tested, she saw that the black mothers were harshly critical in ways that discouraged their children, while the white mothers smiled and gave positive encouragement that invited the children to ask for help.

Flynn also traces the movement of black Americans through the teenage black subculture and then young adulthood in which entry into cognitively demanding leisure and occupational activities is discouraged.

Flynn's third line of argument is that the black/white IQ gap increases with age, which suggests a series of cumulative environmental pressures that discourage the cognitive development of blacks.  Blacks at age 4 have an average IQ of 95.4.  By age 24, this average has dropped to somewhere around 85.

Flynn's fourth line of argument is that there is now evidence that in recent decades about one third of the traditional black-white IQ gap has disappeared--from 15 to 10 points.  This indicates some improvement in American black life to make it more conducive to cognitive development.

Finally, Flynn's fifth line of argument is that for which he is famous--the "Flynn effect."  Average IQ scores in the United States went up at least 30 points in the twentieth century.  Flynn surmises that this massive IQ gain began in the industrial revolution and has continued in scientifically and technologically advanced developed nations, because the social environment in modern societies is much more cognitively demanding than in premodern societies.

If American blacks of 2002 are normed on American whites of 1947-48, the black IQ is 104.31.  This by itself does not prove that the black-white IQ gap is purely environmental, but it certainly shows that this is possible.  Similarly, the lowest average IQ scores in the world are in the developing societies of sub-Saharan Africa.  But these scores today are about the same as those for Americans in 1900.  So as modernization spreads to the developing societies, they could experience the same massive gains in IQ that have occurred in the United States and other developed nations.

If all of these arguments are plausible, then they support a persuasive but not demonstrative conclusion that black and white Americans begin at conception with roughly equal genetic propensities for the high cognitive functioning required to be successful in modern industrialized societies, and that the IQ gap has arisen from the environmental effects of a black subculture that hinders cognitive development.

What difference does it make morally and politically if we take the side of the environmentalists like Flynn or the side of the hereditarians like Jensen and Murray?  Flynn suggests that it might make little difference:
"If there is a genetic component in the racial IQ gap, blacks as a group will always have less favorable statistics compared to whites for academic achievement, occupation, income, and mortality.  However, the intense feelings that surround this question are largely a product of human misery.  If America afforded access to a good life to all of its citizens, blacks would have about as much interest in why there are fewer black than Irish doctors as Irish have about why there are fewer Irish than Chinese accountants." (111)
If I understand correctly what Flynn is saying here, he is agreeing with Murray that genetically based racial differences in average intelligence and social behavior should be "no big deal" in a free society with equality of opportunity in which there's a chance for all to find valued places for themselves in society.  In such a society, we would judge people as individuals and not as people determined by the average traits of their groups.  I noted this in my post last summer on Murray's lecture at the Mont Pelerin Society conference in the Galapagos Islands. 

But notice that while Murray sees this as supporting classical liberalism or libertarianism, Flynn thinks we need Social Democracy or Democratic Socialism that enforces welfare state policies and a redistribution of income to create truly equal opportunities.   For Flynn, it seems, we need the coercive intervention of the state to correct the unfair and undeserved disadvantages that come either from bad genes or bad environments.

Some of these points are developed in other posts here and here.


FredR said...

Seems like the second line of argument could be used as evidence for either side.

Larry Arnhart said...

I know what you're saying. If there's a genetic gap, that would influence the learning environment. But the Elsie Moore study shows that black children adopted by white parents are capable of benefiting from the cognitively enriched environment of a white family, suggesting that black children are equal to white children in genetic potential for cultural learning.

Anonymous said...

A few points of refutation for Flynn:

Minnesota Twin Study: Black identical twins separated at birth, where one was raised in white affluent household and the other in poorer household, end up with same IQs around age of 20.

Flynn actually got data wrong on blacks in Germany. What you are dealing with in Germany is selective immigration. Higher IQ Africans going to Germany, but these blacks aren’t representative of the averages of their countries, which often have IQs of only 70 or so. (Also Africans countries don’t have American ghetto culture and yet black Africans have lower IQs than American blacks on average.) (Regarding selective immigration, you also see this with Indians in the USA — average IQ of India only 82 but the far right side of this bell curve tends to go to USA.)

Poor whites, on average, score higher on SAT than rich blacks. (See recent Sailer post with data.)

Larry Arnhart said...

Could you give me the citation for the study of black identical twins reared apart? Were some reared in white adoptive families and some in black adoptive families?

In some studies of adoption, those black babies adopted into white families have higher IQs than those black babies adopted into black families.

Anonymous said...

Here's a review of new book on Minnesota twin study:

I think this may be the only review of the book, although it was published by Harvard Press.

Larry Arnhart said...

Flynn said nothing about Africans immigrating to Germany. He was talking about the offspring of American black soldiers marrying German women as compared with the offspring of American white soldiers marrying German women.

Larry Arnhart said...

This book by Nancy Segal says nothing about identical black twins reared apart. So where is the study to which you referred?

Anonymous said...

Here's Rindermann surveying all the latest studies on African cognitive ability:

I agree with you about the fairness of Flynn. Flynn isn't even sure the Flynn effect is real.

Larry Arnhart said...

Flynn never denies the reality of the Flynn effect.

Flynn emphasizes that the average IQ for Africans today is about the same as it was for white Americans in 1900. That shows that the Flynn effect could raise African IQ just as much it has raised American white IQ.

Larry Arnhart said...

As far as I know, there are no studies that indicate that black identical twins reared apart--one twin in a black family and one in a white family--show exactly the same IQ. Does anyone have any evidence to contradict this?

Anonymous said...

Wait, so those whose mothers were German and fathers were African-American scored somewhat between the black and white averages? How in the world does that disprove hereditarianism? Seems to absolutely confirm it in that if you have white genes you score higher.
Elsewhere you have judged it plausible that Ashkenazi Jews have higher intelligence. (See Steven Pinker's great series of videos on this on YouTube). It seems like it has become acceptable to say that Jews are smarter but everyone else is identical. (Ridiculous to believe that one one group is different, but it is progress.) Soon it will become acceptable to admit that Asians are smarter as the evidence become overwhelming. But never will it be acceptable to say that whites are smarter than any other group.

Larry Arnhart said...

No, the mean IQs of the two groups--the white and half-black children--were virtually identical. So there was no advantage in having a white father rather than a black father.

This shows that the root causes of the black-white IQ gap in America disappeared in Germany. When black genes were transplanted into white German women, the half-black children grew up in a nation with no black subculture.

Luke Lea said...

Doesn't created equal mean equal rights under the law? And maybe that everyone's future welfare have an equal claim to consideration when it comes to formulating our nation's trade, tax, and immigration policies, etc.? As opposed to government of the smartest, by the smartest, and for the smartest?

candid_observer said...

If you have a sincere interest in getting to the bottom of the cause of the gap, I think you need to come to terms with the hereditarian view as argued by some of its abler proponents.

Here is a paper by Jensen and Rushton that answers many of the objections to the hereditarian position:

Don't allow Flynn to pick his cherries without a rebuttal.

Anonymous said...


On the Elsie Moore study-- the kids were tested at 7-10 years of age. Hereditarians acknowledge that environment plays a significant role at that age.

Need to look at late adolescence, at a minimum, but heritability increases up to full adulthood (early 20s).

Anonymous said...

HBD + meritocracy = hereditary aristocracy

Sean said...

"Or can we affirm the equal dignity of all human beings as a moral and political principle that has nothing to do with the scientific question of whether human beings are in fact equal or unequal in their genetic nature,"

I would say that on the face of it such a political principle would mandate open borders. Because people who are currently denied the right to enter because they were born in other countries could claim it violates their human dignity to be refused entry, (and they could claim it is racism too).

So in practice, as yet, the proposed equal human dignity principle is within the defined bounds of a nation state. If the principle is proposed to be truly universal then that ought to be made clear, especially in a discussion that is about racial discrimination.

I believe Flynn now says the IQ gap being subcultural - environmental is not provable, either way. I'm sure Flynn is very familiar with Moore's study, but is wary of staking much in the way of genralisations on it.

I would point out though that there are many African Americans who grow up with a middle class ethos living among white people. There is research showing there was a whole class of educated blacks who left black areas, and it was after they left that black areas became so 'subcutural'.

So we don't know enough to say if the middle class blacks who left black areas were the cultural or genetic cream. The facts are open to either interpretation.