Orwell Award Announcement SusanOhanian.Org Home

All Brains Are the Same Color

Susan Notes:

The following letters were written in response to the article All Brains Are the Same Color.

To the Editor:

Richard E. Nisbett ("All Brains Are the Same Color," Op-Ed, Dec. 9) does the black-white I.Q. debate a service by adroitly picking apart hereditarians' arguments.

What's always odd about I.Q. discussions, however, is that I.Q. is used synonymously with intelligence. It's pretty hard to argue that on average blacks aren't as smart as whites without really knowing what intelligence is or what I.Q. tests measure.

I.Q. tests were created in the early 1900s before scientists had sufficient understanding of the brain or genetics. They were cobbled together with no real intelligence theory - developed and adapted to test children in French classrooms, immigrants at Ellis Island and soldiers in the Army during World War I - and they have changed very little over time.

If we want intelligence tests, we need to devise new ones based on actual scientific theory rather than Victorian and Progressive Era puffery. Until then, at the very least, we should have a healthy agnosticism about who is smarter than whom.

Stephen Murdoch
Santa Barbara, Calif., Dec. 10, 2007
The writer is the author of a book about the history of I.Q. tests.
To the Editor:

As Richard E. Nisbett shows, the evidence now indicates that the black-white gap is environmental in origin and can be reduced through environmental influences. The most recent evidence on this point comes from the long-term trend data from the National Assessment of Educational Progress (the nation's report card).

Between the early 1970s and 2004, the reading and math scores of black children have risen faster than the scores for white children. Among 9-year-olds, black children have closed more than a third of the black-white gap that existed in the early 1970s. Progress has also been made by 13-year-olds and 17-year-olds.

Changes in genetic endowment cannot explain these gains over time. Rather, the narrowing of the gaps suggests that improvements in home and school environments play causal roles.

Jane Waldfogel
New York, Dec. 10, 2007
The writer is a professor of social work and public affairs at the Columbia University School of Social Work.
To the Editor:

I.Q. is not an inherent trait - it is an invention that measures how much a person knows within one's cultural context, which is why the environment makes such a profound difference in one's score.

I.Q. tests are notoriously biased against anyone who is not white, male and middle class. Numerous studies have shown that it is not a valid measure of intelligence and, indeed, even white people who come from other cultures score poorly on the tests.

The idea that psychologists are still trying to find racial differences in I.Q. scores is maddening. Moreover, we know that there are far more genetic differences within races than between them.

The real point of interest is why people do this research in the first place. These studies tell us nothing about intelligence, black people, white people, genetics or environment. What they really show is the inherent racism of the ones doing the research.

Leeat Granek
Toronto, Dec. 10, 2007
To the Editor:

Having seen many brains at autopsy and in teaching labs, I can confirm the statement that "All Brains Are the Same Color." But the discussion of genetic determination of intellectual capacity falls short of the mark.

It is not the genetic DNA in a cell that determines what a cell is and how it performs; it is, rather, which genes are turned on and when. Turning a gene on or off can be controlled by a wide variety of factors in life: toxins, learning, disease, hormones, drugs, diet - the list is numberless.

We now know enough about the fine structure of the brain, the proteins involved and the roles they play in learning, cognition, memory and other components of intelligence to understand that the DNA of genes are, generally, many steps removed from determining these capacities. Any study of the genetics of possible racial differences in intelligence must be based not on genes but on knowledge of the fine structure and proteins of the brain. These can provide objective, quantifiable measures.

Such a study must also be conducted on groups that have been rigorously matched on the basis of all the factors that can affect gene expression and protein production and processing, like age, gender, environment, diet, drug and toxin exposure - a daunting, if not impossible, task.

Paul Coleman
Sun City, Ariz., Dec. 10, 2007
The writer is senior scientist and co-director of Alzheimer's research at Sun Health Research Institute.
To the Editor:

As heartening as I found Richard E. Nisbett's arguments against a correlation between race and intelligence, I find it difficult to overlook the fact that one of the world's most eminent scientists, James D. Watson, recently lost his job for taking the opposite position.

Under such circumstances, essays like Professor Nisbett's take on the air of dogma. One is left to wonder what researchers might find or say if their careers and reputations weren't threatened by academic McCarthyism.

Joshua P. Hill
New London, Conn., Dec. 10, 2007
To the Editor:

Perhaps Richard E. Nisbett's report on studies that show the effect of environment on I.Q. scores has provided an answer to a question I have pondered for many years. When I was in high school, I scored 115 on an I.Q. test, but when I had another I.Q. test many years later, I scored over 130. Why the increase?

My skin color hadn't changed, but my environment certainly had. I grew up in a small town with a father who had dropped out of school in the sixth grade and a mother who was the only one of six children who graduated from high school.

When I took the second I.Q. test some 30 years later, I was living in Baltimore because my husband was a tenured professor at Johns Hopkins University. I had just completed a master's degree and was thinking of applying for admission to a doctoral program.

Lucille Coleman
Baltimore, Dec. 9, 2007

By Richard E. Nisbett

Ann Arbor, Mich.

JAMES WATSON, the 1962 Nobel laureate, recently asserted that he was âinherently gloomy about the prospect of Africaâ and its citizens because âall our social policies are based on the fact that their intelligence is the same as ours â" whereas all the testing says not really.â

Dr. Watsonâs remarks created a huge stir because they implied that blacks were genetically inferior to whites, and the controversy resulted in his resignation as chancellor of Cold Spring Harbor Laboratory. But was he right? Is there a genetic difference between blacks and whites that condemns blacks in perpetuity to be less intelligent?

The first notable public airing of the scientific question came in a 1969 article in The Harvard Educational Review by Arthur Jensen, a psychologist at the University of California, Berkeley. Dr. Jensen maintained that a 15-point difference in I.Q. between blacks and whites was mostly due to a genetic difference between the races that could never be erased. But his argument gave a misleading account of the evidence. And others who later made the same argument â" Richard Herrnstein and Charles Murray in âThe Bell Curve,â in 1994, for example, and just recently, William Saletan in a series of articles on Slate â" have made the same mistake.

In fact, the evidence heavily favors the view that race differences in I.Q. are environmental in origin, not genetic.

The hereditarians begin with the assertion that 60 percent to 80 percent of variation in I.Q. is genetically determined. However, most estimates of heritability have been based almost exclusively on studies of middle-class groups. For the poor, a group that includes a substantial proportion of minorities, heritability of I.Q. is very low, in the range of 10 percent to 20 percent, according to recent research by Eric Turkheimer at the University of Virginia. This means that for the poor, improvements in environment have great potential to bring about increases in I.Q.

In any case, the degree of heritability of a characteristic tells us nothing about how much the environment can affect it. Even when a trait is highly heritable (think of the height of corn plants), modifiability can also be great (think of the difference growing conditions can make).

Nearly all the evidence suggesting a genetic basis for the I.Q. differential is indirect. There is, for example, the evidence that brain size is correlated with intelligence, and that blacks have smaller brains than whites. But the brain size difference between men and women is substantially greater than that between blacks and whites, yet men and women score the same, on average, on I.Q. tests. Likewise, a group of people in a community in Ecuador have a genetic anomaly that produces extremely small head sizes â" and hence brain sizes. Yet their intelligence is as high as that of their unaffected relatives.

Why rely on such misleading and indirect findings when we have much more direct evidence about the basis for the I.Q. gap? About 25 percent of the genes in the American black population are European, meaning that the genes of any individual can range from 100 percent African to mostly European. If European intelligence genes are superior, then blacks who have relatively more European genes ought to have higher I.Q.âs than those who have more African genes. But it turns out that skin color and ânegroidnessâ of features â" both measures of the degree of a black personâs European ancestry â" are only weakly associated with I.Q. (even though we might well expect a moderately high association due to the social advantages of such features).

During World War II, both black and white American soldiers fathered children with German women. Thus some of these children had 100 percent European heritage and some had substantial African heritage. Tested in later childhood, the German children of the white fathers were found to have an average I.Q. of 97, and those of the black fathers had an average of 96.5, a trivial difference.

If European genes conferred an advantage, we would expect that the smartest blacks would have substantial European heritage. But when a group of investigators sought out the very brightest black children in the Chicago school system and asked them about the race of their parents and grandparents, these children were found to have no greater degree of European ancestry than blacks in the population at large.

Most tellingly, blood-typing tests have been used to assess the degree to which black individuals have European genes. The blood group assays show no association between degree of European heritage and I.Q. Similarly, the blood groups most closely associated with high intellectual performance among blacks are no more European in origin than other blood groups.

The closest thing to direct evidence that the hereditarians have is a study from the 1970s showing that black children who had been adopted by white parents had lower I.Q.âs than those of mixed-race children adopted by white parents. But, as the researchers acknowledged, the study had many flaws; for instance, the black children had been adopted at a substantially later age than the mixed-race children, and later age at adoption is associated with lower I.Q.

A superior adoption study â" and one not discussed by the hereditarians â" was carried out at Arizona State University by the psychologist Elsie Moore, who looked at black and mixed-race children adopted by middle-class families, either black or white, and found no difference in I.Q. between the black and mixed-race children. Most telling is Dr. Mooreâs finding that children adopted by white families had I.Q.âs 13 points higher than those of children adopted by black families. The environments that even middle-class black children grow up in are not as favorable for the development of I.Q. as those of middle-class whites.

Important recent psychological research helps to pinpoint just what factors shape differences in I.Q. scores. Joseph Fagan of Case Western Reserve University and Cynthia Holland of Cuyahoga Community College tested blacks and whites on their knowledge of, and their ability to learn and reason with, words and concepts. The whites had substantially more knowledge of the various words and concepts, but when participants were tested on their ability to learn new words, either from dictionary definitions or by learning their meaning in context, the blacks did just as well as the whites.

Whites showed better comprehension of sayings, better ability to recognize similarities and better facility with analogies â" when solutions required knowledge of words and concepts that were more likely to be known to whites than to blacks. But when these kinds of reasoning were tested with words and concepts known equally well to blacks and whites, there were no differences. Within each race, prior knowledge predicted learning and reasoning, but between the races it was prior knowledge only that differed.

What do we know about the effects of environment?

That environment can markedly influence I.Q. is demonstrated by the so-called Flynn Effect. James Flynn, a philosopher and I.Q. researcher in New Zealand, has established that in the Western world as a whole, I.Q. increased markedly from 1947 to 2002. In the United States alone, it went up by 18 points. Our genes could not have changed enough over such a brief period to account for the shift; it must have been the result of powerful social factors. And if such factors could produce changes over time for the population as a whole, they could also produce big differences between subpopulations at any given time.

In fact, we know that the I.Q. difference between black and white 12-year-olds has dropped to 9.5 points from 15 points in the last 30 years â" a period that was more favorable for blacks in many ways than the preceding era. Black progress on the National Assessment of Educational Progress shows equivalent gains. Reading and math improvement has been modest for whites but substantial for blacks.

Most important, we know that interventions at every age from infancy to college can reduce racial gaps in both I.Q. and academic achievement, sometimes by substantial amounts in surprisingly little time. This mutability is further evidence that the I.Q. difference has environmental, not genetic, causes. And it should encourage us, as a society, to see that all children receive ample opportunity to develop their minds.

Richard E. Nisbett, a professor of psychology at the University of Michigan, is the author of âThe Geography of Thought: How Asians and Westerners Think Differently and Why.â

— Richard E. Nisbett
New York Times


This site contains copyrighted material the use of which has not always been specifically authorized by the copyright owner. We are making such material available in our efforts to advance understanding of education issues vital to a democracy. We believe this constitutes a 'fair use' of any such copyrighted material as provided for in section 107 of the US Copyright Law. In accordance with Title 17 U.S.C. Section 107, the material on this site is distributed without profit to those who have expressed a prior interest in receiving the included information for research and educational purposes. For more information click here. If you wish to use copyrighted material from this site for purposes of your own that go beyond 'fair use', you must obtain permission from the copyright owner.