In this video I consider racial differences in average IQ scores. This controversy reached a peak with the publication of “The Bell Curve” by Richard Herrnstein and Charles Murray in 1994. This led to publication of several papers on race and IQ stating that IQ is considered valid, reliable, and heritable, and that while group differences exist, the causes of these differences are not clearly understood. While concepts of race, environmental and societal forces, and genes may or may not all contribute to observed differences between groups, it’s important to remember that knowing an individual’s group membership doesn’t tell one anything about that individual’s IQ score.
The Bell Curve Explained (Charles Murray): http://www.aei.org/spotlight/the-bell…
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Video Transcript
Hi, I’m Michael Corayer and this is Psych Exam Review. In this video we’re going to look at a controversial subject and this is racial differences in IQ. This controversy reached a peak in 1994 with the publication of the book “The Bell Curve” by Richard Herrnstein and Charles Murray.
Now most of The Bell Curve is not actually about race; it’s about IQ in general and it’s about a fear that American society was becoming increasingly stratified on the basis of IQ. And so the idea was that starting in the second half of the 20th century colleges were becoming increasingly selective of students purely on the basis of IQ through tests like the SAT. And the good side of this is that it creates more of a meritocracy. In other words, the students who have the highest general cognitive ability all get selected into these elite schools and this was done regardless of their family background, you know, their social standing or even their race and it brings them together. Now, the downside is that it might isolate them from the rest of society and it might have the potential to form what they called a “cognitive elite“.
Where these students all go to school together and then they all go on to work in jobs that everyone has higher IQ, and this can lead to some isolation between this cognitive elite and the rest of society. And this is an issue that I think we see today in some discussions of places like Silicon Valley and accusations that it’s disconnected from the rest of American society. I think this could relate to some of Herrnstein and Murray’s claims about a growing cognitive elite.
But that’s not what the controversy over The Bell Curve focused on. It focused on the suggestion that there are racial differences in IQ and these differences may be in part due to genetics. Now in response to this controversy over the book, a series of statements about intelligence was published in the Wall Street Journal and signed by dozens of intelligence researchers. This was called Mainstream Science on Intelligence. It was later republished in the journal Intelligence with lead author Linda Gottfredson and what this article did was it made a few statements about IQ that these researchers all believed to be true. And many of these statements matched with statements from The Bell Curve.
And so the first statement is that IQ is valid. So they said you can’t really dismiss IQ as a general concept. It’s a valid construct and not only that, it’s reliable. So it’s actually one of the best assessments of a psychological trait that we have. If you don’t believe in the concept of IQ then you really can’t believe in any concept in psychology. It said IQ is a valid construct, it is reliable, and it does predict future outcomes. Not only that, it’s been shown to be heritable. In other words, people have different IQs and part of the reason for these differences between individuals on IQ scores is that people have different genes.
So there is a genetic component to IQ and in The Bell Curve Herrnstein and Murray say that a reasonable estimate is around 0.6 plus or minus .2 which is essentially what we’ve seen already in the previous video on heritability of IQ; that it ranges somewhere between 0.4 and 0.8. And the third statement is that there are differences between racial groups in terms of average IQ score and that these have been consistently reported. So what are these group differences in average IQ? Well, if we look at the curves for IQ, they say, if we look at the curve for white Americans, the curve for black Americans is about fifteen points lower. The curve for Hispanic Americans was somewhere between these two and the curves for East Asian and some Jewish populations slightly higher. Ok, but as you can see there’s a great deal of overlap in all of these curves and there’s some evidence that these gaps have shrunk in some cases. So that the gap between white and black Americans may be getting smaller and current estimates may be only around 10 points rather than 15 at the time of the publication of The Bell Curve.
Ok, so this Mainstream Science on Intelligence was considered by some to be overly supportive of the views of The Bell Curve and so the American Psychological Association put together a task force, which then published a paper with lead author Ulric Neisser in 1996 called Intelligence: Knowns and Unknowns. And while this recognized these statements as being some of the known aspects of intelligence, it emphasized that there are many unknowns. And in particular that the causes of these differences between groups are not yet known. So even though we might recognize that, yes these group differences have been consistently reported, we don’t know why these differences are occurring and we shouldn’t make the assumption that it’s due to genetic differences between groups.
So this brings us to one of the main ideas of this paper was the emphasis that within-group differences can be genetic without meaning that between-group differences are genetic. So what does that mean? Well, one way of explaining this, often attributed to Richard Lewontin, is the idea that you take a handful of seeds and let’s say there’s two different types of seeds here and they have very different genes. So I’ve got this handful of seeds and they have different genes and I plant them on some field here, on some fertile soil, and when I look at these plants later I see something like this, right? And the idea is well, this plant and this plant, why do they have such different heights? And the idea is well, this within-group difference here would probably be because these seeds have different genes, right? There were two different genetic profiles of these plants here and so the reason that this plant is so much taller than this plant is because of genes. So there would be a high heritability score here.
But if I took another handful of the same seeds and I toss them all onto some really poor soil and so I get, you know, something like this later. That just because the difference between this plant and this plant is due to genes, a within-group difference, doesn’t mean that the explanation for this plant and this plant is also genes. Because it could be the case in that environment this could actually be the same genetic seed as this one and the reason why their heights are so different is that their environments are different. So just because we have, we have this within-group difference being explained by genes doesn’t mean we can use genes as the basis for explaining between group differences.
This is related to this idea of racial differences. So even though we know that IQ is heritable in terms of individuals varying overall, that doesn’t mean that group differences are also due to genes. Ok, another point that this paper made was if you look at caste-like systems in some societies, so if you have places where there’s sort of a dominant group and a subordinate group within the culture, so you have this caste-like system, you often find differences in the average IQ of people from these two groups and they said that this even occurs occurs when these groups are not racially distinct. The idea is you could have a society where there’s this caste-like system, you have a dominant and subordinate group of people and they get different average IQ scores if you were to look at the curves and this can occur even though these two groups of people don’t have aren’t considered to be different races.
So that would suggest that it’s not a genetic issue explaining this. It has nothing to do with race that’s causing the difference between these two groups but it’s something to do with the societal structure and this brings us to the next point which is what does race really mean? And when we look at these curves for different racial groups it’s important to remember that these are not racial groups identified on the basis of genes. It’s not the case that we look at the genetic profile of somebody and said “okay this person has black genes” or “this person has white genes” or something like that. Not at all, what we did is just ask people you know “are you black or white or Hispanic or Asian or Jewish” or whatever, you know, sort of classification we want to use. And these aren’t clear distinctions; many black Americans have some white ancestors, many white Americans have some black ancestors. There’s a great deal of blurring between these lines. These aren’t unique categories even though we might like to think of them that way. And we might look at these curves and think of them as being two very separate groups when in fact they might not be as separate as we think. So it’s important to remember that determining something like whether somebody is black or white is complicated and the ancestries are blurred.
And in addition to that people are self-selecting, right? So people are being asked “are you black or white?” and people can sort of maybe have some choice in some cases of which they identify as being. And that these are essentially social classifications. So the way that we think about people being black or white is really determined by the society that we’re in, it’s not determined, we don’t look at some of these genetic profiles. So we don’t really know enough about the racial differences in terms of genetics in order to draw any conclusions that genetics are causing these differences. Ok, so that’s another thing to consider is the concept of race itself.
Ok, so what do we make of all this? How do we explain these gaps? Well I said this is a controversial topic and this can be seen regardless of how do we try to explain these gaps. Now Richard Herrnstein unfortunately passed away before the publication of The Bell Curve but Charles Murray faced a great deal of criticism for this book. He was essentially shunned for decades and even recently there were protests where he was supposed to speak at a college. And so if you suggest that genes are responsible for this difference, you face all sorts of accusations. Murray has been accused of being racist, being a eugenicist, being a Nazi, simply for suggesting that maybe genes are part of this explanation for these gaps between average performance of different racial groups.
On the other hand, you might focus on environment. Say, well maybe there’s something about the environments that are different and that’s causing these performance gaps. And so one researcher who has emphasized the role of environment on explaining these differences is James Flynn and, somewhat ironically, Flynn has also been accused of being racist. Because he suggested that well maybe there’s some differences in subcultures. In other words, maybe we shouldn’t think of black Americans and white Americans as really living in the same culture. Maybe there are subcultures and maybe those subcultures diff in ways that are having some impact on IQ. And because of this suggestion that there could be differences in sort of black subculture or white subculture, he’s been accused of suggesting that some of these subcultures maybe are superior to others. And then he’s been accused of being a racist as well.
So in some ways it seems no matter what explanation you try to go for you run the risk of being considered racist merely for discussing this topic, that there are measurable differences between groups of people. So, how should we proceed? Well, the most important thing and something that I think all of these researchers would agree on and this is something that was clearly stated in The Bell Curve by Herrnstein and Murray was the best way to operate is to always treat people as individuals. That knowing that there are average differences between groups doesn’t tell you anything about an individual’s IQ.
In other words, if we look at all of these overlapping curves here; they’re all overlapping and they’re actually pretty close together. And so knowing somebody’s race doesn’t tell you anything about their IQ. They could be anywhere on that line and so they could be you know in the top you know 0.1% of IQ regardless of which racial group they’re a member of. Or they could be lower or higher or average, you really have no way of knowing? So knowing somebody’s race doesn’t tell you anything about their IQ.
This is just like we saw when we talked about sex differences in IQ. Knowing that somebody’s male or female doesn’t tell you anything about their IQ either, even though we know that there are some average differences between all members of the population. Ok, so that’s really the most important point that we get from all of this is that people should always be treated as individuals. And that while we want to try to uncover the causes of these group differences, we want to understand IQ better when it comes to individuals, we can’t draw any conclusions about IQ on the basis of race.
Ok, I hope you found this helpful, if so, please like the video and subscribe to the channel for more. Thanks for watching!
