Intelligence and race is not a topic that I am interested in, and researching this topic had never previously crossed my mind. My researcher’s eyes have only recently been turned to a review of the literature on this topic because of some controversy that was brought to my attention involving neuroscientist and philosopher Sam Harris and his interview with researcher Charles Murray. I had not heard of Murray or his book The Bell Curve (1994) before, but I was told that this interview was the smoking gun that proved Sam Harris (and Charles Murray) were little more than racist misguided scientific hacks.
Let me qualify that last statement. I could not remember having heard of Murray, but when I typed his name into a Facebook search, I found something I shared from April 2014. If I saw someone else share the same post today I would groan in minor frustration, so I was disappointed seeing this post from me.
Of course, men do have larger brains on average; their bodies are on average larger, and it is a well-attested to scientific fact that brain size has a strong correlation with body size. If I told you elephants on average have bigger brains you wouldn’t mistake me for saying we are inferior and dumber than elephants, would you?
As a side note, the meme I shared cited Where Are the Female Einsteins. However, I found an essay by that title only in archival sources, so I will just cite the article from The Commentary which is basically identical in text (absolutely verbatim regarding the passages will be referring to).
In any case, I should have done my research before sharing the picture because it turned out to be an example of careful quote-mining. The pictured quote implies Murray is impugning the intelligence of women by saying they have slightly smaller brains, but the next sentence in the article has Murray pointing out that “most psychometricians conclude that men and women have the same mean IQ” (Murray, 2005). In other words, he pointed out that slightly smaller mean brain size doesn’t make women any less smart than men.
This isn’t me interpreting based on political bias either. I live in Texas, I voted for Wendy Davis then, and I would still vote for her in a heartbeat if she ran against Greg Abbot again.
Interestingly, Women used to score lower than men on IQ tests, but as the sex discrimination has eased over the decades and women have flowed into schools and universities, the IQ gap shrank until women achieved parity. Now, women actually get more college degrees than men.
Before I go on, let me say that what I am not going to do here is weigh in on whether research on the topic of race and IQ is important, dangerous, necessary, or unnecessary. I am fact-checking. I have a great deal of experience conducting reviews of scientific literature, so that is what I intend to do here. Murray has made claims regarding IQ, and his opponents have made counter-claims. I am only interested in finding out which claims are supported by the academic evidence and which are not; I am not qualified to decide whether or not research on the topic should have been conducted in the first place, what its implications are, or even what the motivations are behind it.
Is IQ a valid construct, and are tests that measure it reliable or biased?
The scientific literature seems to be fairly uniform in its determination of IQ as a valid construct, and it provides ample evidence that it is also a useful and reliable measure. Tommasi et al. (2015) found IQ as measured by the Wechsler Adult Intelligence Scale (WAIS-R) to be valid and significantly predictive of higher educational attainment. A meta-analysis by Schmidt and Hunter (1998) on decades of research found evidence strongly in support of the predictive validity of the SAT, IQ, and other similar tests. The authors found that for an employer looking to hire a person with no previous work history, IQ score was the most predictive single trait of future success. Wagner (1997) determined that cognitive tests such as IQ tests yield substantial power in predicting future job performance, particularly through its indirect effect on job knowledge. Specifically, IQ had a ~.46 correlation on job knowledge, and job knowledge had a ~.30 correlation with job performance (1.0 would be a perfect correlation).
Don’t be mistaken that IQ is the only relevant factor. Wagner (1997) cautioned against seeing IQ as the be-all-end-all, and strongly encourages the use of supplemental measures. Rather than cognitive and emotional traits, simply measuring previous job performance had the best correlation (.89) with future job performance in their analysis. A study by Downey, Lee, and Stough (2011) found that emotional intelligence (EI) predicted success better than a measure of IQ in their particular investigation. Though, on intelligence specifically, Duckworth, Quinn, and Tsukayama (2012) reported that IQ and standardized achievement tests more accurately reflect intelligence, whereas EI reflects self-control and is seen more in report card grades in students.
It seems high natural cognitive ability and the self-discipline to put it into practice are a winning combination. Keep in mind that IQ and EI have a great deal of overlap wherein a person high in one is likely to be high in the other.
Finally, Gignac (2015) found that, while IQ shared about 50% variance with g, it did not tell the whole story. Thus, Gignac urged against considering IQ the only thing that matters when determining general intelligence. IQ scores are valid and helpful, but the scientific community doesn’t have illusory beliefs that it is almighty, or that it is important when determining a person’s value. All human lives have equal value.
Real-world correlates with IQ
In one experiment, Minkov (2017) concluded that in general, low IQ reflects the prevalence of a simplistic and rigid personality. Conversely, a high IQ was found to reflect a fluid, dynamic, and adaptable personality capable of adapting to different situations. Sörberg, Allebeck, and Hemmingsson (2014) found high IQ to be associated with better mental and somatic health. In a meta-analysis, Devine and Philips (2001) reported that Team-level cognitive ability was positively related to team performance, but the magnitude of the relationships appeared to vary as a function of contextual variables. Bates and Gupta (2017) found that individual IQs increase a group’s collective IQ, and thus group performance on tasks such as brainstorming, categorizing ravens, architectural design, and planning a shopping trip.
Of course, there are examples where a person may have a high IQ but as a result of dyslexia, autism, or some other learning, emotional, or developmental disorder doesn’t thrive. But these appear to be exceptions rather than the rule, and a veritable mountain of scholarship attests to that.
None of this should be mistaken to imply that any person should be confident in predicting a successful future for an individual with a higher IQ, or vice versa for an individual with a low IQ. As will be stated over and over throughout this discussion, IQ is an extremely important (probably the most important) factor predicting success, but it is definitely not the only important factor. Moreover, as will also be stated repeatedly, there is drastically more variance between individuals within a population than there is between populations as groups, and as a result, it would be ludicrous to think you can predict an individual’s IQ based on the group he or she belongs to.
Given those caveats, the evidence thus indicates IQ is real, and has real-world effects. Some point out that questions on IQ tests may be written in a way beneficial to one group of people versus another. However, if it was reliably the case that this was a problem, the predictive power of IQ tests should be much lower for the groups supposedly disadvantaged by the wording and construction. In the research, this has not generally been the case. That isn’t to say professionals shouldn’t still strive to identify any problems they’ve missed, or to try to avoid introducing them in the future. They absolutely should. But perfect shouldn’t be the enemy of very good.
Does IQ have biological components?
A point of public layperson contention is whether or not IQ is related to biology or genes in any way. Giles (2006) determined that IQ scores reflect brain structure. Wang, Wee, Suk, Tang, and Shen (2015) were highly successful in predicting IQ based on neuroimaging, supporting the proposition that IQ is related to brain structure.
When adjusting for environmental factors, Becker and Rindermann (2016) found that genetic factors are related to international differences in cognitive ability. However, they explain that genetic factors have a much larger effect at the individual level than at the population/international level. In other words, while genetics is a factor, there is much more variation within populations than between them. This is something Charles Murray himself emphasizes persistantly.
Do races vary in IQ?
An investigation by Rushton and Jensen (2005) reviewed thirty years of research and found that there was evidence of some genetic components relating to the Black-White mean difference in IQ. In a meta-analysis by Roth, Bevier, Bobko, Switzer, and Tyler (2001) explained that a one standard deviation effect size in IQ accurately summarize Black-White differences for college application tests such as the SAT, and reflect overall analyses of tests of g (general intelligence factor) for job applicants in corporate settings. Lynn and Cheng (2013) reported that among 5 year-olds in the UK (n = 14,860), Chinese children had higher IQs (102.06) than white children (100.87), and that white children had higher IQs than ethnic groups such as Indians (96.87), Pakistanis (86.62), and black Africans, Caribbeans, and Other (90.02, 96.68, and 91.95 respectively). Similar results have been reported and replicated in many studies (e.g., Beaver et al., 2013; Fagan & Holland, 2002; Lynn, Backhoff, & Contreras, 2005; Rushton & Ankney, 1995; Spiropoulos, Salisbury, & Van Voorhis, 2014; Vanhanen, 2012).
Cause of racial differences
The exact causes of the mean IQ difference among racial/ethnic groups is not well understood, but environment undoubtedly explains a great deal (if not most) of it. Charles Murray points out that, “In the past few decades, the gap between blacks and whites narrowed by perhaps three IQ points… Improvements in the economic circumstances of blacks, in the quality of the schools they attend, in better public health, and perhaps also diminishing racism may be narrowing the gap” (Herrnstein & Murray, 1994).
Murray gives an analogy to illustrate that environmental differences between the black and white communities affected the IQ difference between the two populations.
“Take two handfuls of genetically identical seed corn and plant one handful in Iowa, the other in the Mojave Desert, and let nature (i.e., the environment) rake its course.’ The seeds will grow in Iowa, not in the Mojave, and the result will have nothing to do with genetic differences. The environment for American blacks has been closer to the Mojave and the environment for American whites has been closer to Iowa. ”
Murray also makes the claim, though, that genetics likely plays at least some small part in the average differences in mean IQ scores. The evidence thus reviewed here suggests that some quantity of genetic components cannot be ruled out. That said, my review of the literature was not even close to exhaustive, and I do not claim to be an expert. I merely used keywords like “IQ,” “heritability,” and “race” in the an online university database, and restricted to search to peer-reviewed journals. This gave me the sample of articles I read and cited.
The hypothesis that genetics plays some role in the IQ difference between races is a claim Murray’s critics attack often, seemingly because they feel its implications would be disastrous for civil rights. But Murray’s claim can be correct—not that it is correct—concurrently with civil rights advocates being correct (they are indeed correct) that racism is still alive and well and contributing strongly to social problems hurting the black community.
In practice, Murray said that the exact causes of the Black-White mean difference in IQ or the ratio of genetic to environmental should not matter.
“If you were a government official in charge of educational expenditures and programs, you would continue to try to improve the education of inner-city blacks, partly out of a belief that everyone should be educated to the limits of his ability, partly out of fairness to the individuals of every degree of ability within that population—but also, let it be emphasized, out of a hardheaded calculation that the net social and economic return of a dollar spent on the elementary and secondary education of a student does not depend on the heritability of a group difference in IQ .”
As has already been stated, there is an extremely high level of statistical variance among individuals within groups; much more than between groups. Because of this, in the book Murray says that despite knowing the mean differences, “it should make no practical difference in how individuals deal with each other.” On page 271 of The Bell Curve, Murray says “If all the ethnic differences in intelligence evaporated overnight, most of the intellectual variation in America would endure.” This is because the sum total of the variance among people in America is greater between individuals than between ethnic groups. I know I am repeating myself, but this point needs to be emphasized.
Because of the variance, any racists who want to use IQ to ignore the systemic racism indicated by (among many other things) the high incarceration rate of blacks are abysmally wrong. Racists trying to use IQ to dismiss any of the systemic wrongs affecting the black community would be hopelessly deluding themselves.
Racists and their use of some isolated “facts”
There is no doubt that repugnant racists with very little understanding of statistics or science will attempt to use some of these facts to support their bigoted and false world-view of white superiority. But the facts do not support their world-view or conclusions, and their attempts to misuse the facts should be vigorously fought.
However, the proper way to fight these abominable people is not to deny the facts they’re misusing. The proper way is to attack their conclusions based on their intentional misunderstandings of the facts.
Murray’s political positions
You do not have to agree with Murray’s conclusions about public policy to conclude that he is likely not a racist. Murray is generally regarded by dispassionate sources as a center-Right libertarian-minded individual. I personally find a lot to disagree with him about regarding social policy—universal basic income is pleasantly not among those disagreements—and I am not shackled to his world-view just by admitting that the claims of his I’ve reviewed accurately reflect the scientific evidence. I am not a psychic, I don’t know what is truly in Murray’s head, but after reading the chapter of The Bell Curve about race, I did not find anything that indicated to me that he was racist.
Sam Harris podcast with Murray
In the podcast, Murray basically says the same thing he says in the excerpts of the book I cited, right down to the analogy with corn planted in the Mojave versus Ohio. I can see how a person sensitive to the topic could see Murray and Harris as being overly matter-of-fact about the data, that they are perhaps overly dismissive (though I don’t think they were), or that they don’t spend enough time trying to placate the fears of people about the facts. But if Murray is a racist, nothing that I have read in The Bell Curve, his article in The Commentary, or anything he said while on the podcast of Sam Harris is convincing evidence of it for me. As far as his representation of the scientific evidence goes, he is not lying about what the academic studies have found that IQ is valid measure, and that there are mean differences in IQ between certain groups.
Ezra Klein’s conclusion that that Murray in his book and on the podcast determined that “racial IQ gap cannot plausibly be closed” doesn’t seem reasonable to me. Murray mentioned in the book that changes in environment in fact have been closing the gap. Klein also said Murray claimed said that the IQ difference was primarily “driven by genetic racial differences,” which he doesn’t say, either in the podcast or in the book from what I can tell. Indeed, Murray repeatedly indicates that the environment played a role in the gap (as you can see in my earlier quotations from his book).
I can see how some of Murray’s statements may have sounded ambiguous to non-experts, or that they sounded odd. But it is easy to read the book and see what he meant by various statements in the podcast. It seems as though the people opposing him are interpreting every statement in the worst, least charitable possible way because they were determined to confirm their existing belief that he was a racist. Most of them haven’t come near actually reading the book.
I did not have any existing belief on Murray to begin with (certainly not a positive one, as my shared picture at the beginning of this article shows), so I hardly had anything to confirm. I’m also a diversity-preaching immigrant-advocating liberal, so I don’t believe I had ideological biases that would dispose me to overlooking racist beliefs if I thought they were there.
I don’t find the label of “racialist” (a thinly veiled accusation of racist or white supremacist) bequeathed in a Vox article about the podcast is reasonable. Murray may very well be wrong about the implications and consequences of the Black-White IQ difference (the Vox article emphatically acknowledged the difference exists). But Murray speculating in, what appears to me, good faith about the possible consequences is not evidence of racism. This especially seems to be the case given that Murray repeatedly says in The Bell Curve that it should be irrelevant to how any individual is treated, and that public policy-makers should continue helping the black community in the same way they would absent the knowledge of an IQ gap.
The Vox article is written for the most part by psychologist Eric Turkheimer, and apparently signed off on by some other better-known psychologists to give it extra weight. I know in a lot of contentious controversies like this it is common for people to just cherry-pick whatever expert agrees with them. That seems to be what Ezra Klein did, but that is not what I did. I did a review of the literature myself first and foremost.
But since I am not so delusional as to believe I for sure know what the literature indicated, I looked to see what some other prominent psychologists thought. I found that one of the most famous living American cognitive psychologist, Steven Pinker (90,000+ google scholar citations), has recently called Harris “whip-smart” and an “original thinker,”and has aimed jibes at Murray’s opposition.
I also found a response to the Vox Article by psychologist Richard Haier which made drastically more sense, and reflected my personal experience going through the literature. Haier said “Sam Harris is not an expert in intelligence research but I am. After hearing the podcast, I emailed congratulations to him and Murray for conducting an informative discussion of complex and controversial issues. Every point they enumerated as having broad support among intelligence researchers is correct.” Hairer also cites an article by an APA task force which vindicates Murray’s core claims.
Lastly, one of the authors of the Vox article, Kathryn Paige Harden, went on Harris’ podcast about two years later and discussed the Charles Murray podcast at length. She appeared to walk back much of the criticism in the Vox article, and clearly did no feel Harris was a racist (she went on his podcast for one).
This article was not an advocacy for a special interest in race and IQ. Like I said at the beginning, I have little interest in the topic outside of trying to figure out the controversy as it related to Sam Harris. This article wasn’t even meant to suggest all or most of Charles Murray’s personal or professional conclusions are correct. I was interested only in seeing if his primary claims stood the scrutiny of a brief personal review of the literature, if his work indicated racism, and by proxy if that indicated Sam Harris sympathized with a racist.
I found nothing indicating Murray was a racist (or Sam Harris). Indeed, what I found indicated Murray was not racist, and that his claims and questions were in good faith. The claims by Murray that IQ is real, that different ethnic populations have different mean IQs, and that these differences are largely a environmental and possibly in small part genetic (nature and nurture) was supported by the scientific literature that I found.
If you seek to bring something to my attention that I missed in this article, please cite sources and at least make an attempt to follow the data regardless of whether it makes you uncomfortable or not. I acknowledge I could have missed an important piece of data, so don’t accuse me of intentionally leaving something out if I did miss something.
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