Is IQ innate?

In June 2005  Prof Rushton and University of California psychology professor Arthur Jensen published a 60-page study in Psychology, Public Policy and Law in which they concluded: “Neither the existence nor the size of race differences in IQ are a matter of dispute, only their cause”. Rushton revisited Andrew Duffy The Ottawa Citizen October 1, 2005 http://www.canada.com/ottawa/ottawacitizen/news/story.html?id=6c9fe76b-f1 bd-4cfb-baa8-5d006efdf650&page=1

What is the cause? Is it nurture or Nature? That of course is the question that makes the very notion of IQ as a meaningful measure of mental ability anathema to most white liberals, which means most people with power and influence in the West today.

Liberals dislike the idea of IQ tests because it goes against the belief which underpins modern liberalism, namely, that no meaningful distinctions can be made between people as a group.  A liberal may allow that a particular person may be good bad or indifferent in some respect but not the group. Many liberals in practice go beyond the repudiation of group distinctions and apply the idea to the individual, claiming (or at least implying by their behaviour) that if someone is deficient in some quality it is merely a matter of circumstances and upbringing.

The liberal would not necessarily be keen on IQ testing even if IQ could be shown to be entirely the product of the environment, because that which is the consequence of upbringing may be as fixed as that which is innate. Unless it could be shown that IQ could be altered radically at every stage of life the liberal would be left with the awkward problem of what to do with those whose IQ is already fixed. The liberal would have the further problem of how to alter society to prevent future disadvantage due to the environment If some magic genetic engineering bullet or other artificial means such as cybernetic enhancement could not be found do the job, the only plausible means to improve IQ would be to radically reduce the differences in the environments in which children are raised. If it was material differences which mattered that would be difficult enough, but what if it was found that the primary causative agent of the development of IQ was the influence of family and peers? How would the child of parents who lacked intellect or parents who had little interest in their child be compensated for a poor environment? As for material differences, it is noteworthy that modern liberals show very little practical interest in reducing material inequality. Indeed, most have bought into the free trade, free market ideology where property is sacrosanct.

There is a further problem for latter-day liberals: the fact that it is blacks who have the lowest average IQ. Blacks are the ultimate politically correct group for white liberals. If it was whites who had the lowest average IQ it is doubtful that liberals would be so utterly hostile to the idea of IQ as an innate quality. Indeed, it is probable that liberals would use the fact to bolster their claims that on average blacks have poor social outcomes compared with whites and Asians because of racism.

It is not only white liberals who have an emotional problem with IQ as an innate quality. Most of the developing world (essentially everywhere but those countries with Asian populations) has a problem because their national IQs are substantially lower than those of the advanced nations. No people are going to take kindly to the idea that they are as a people innately inferior in some important respect.

What applies to nations applies to any member of a low IQ group anywhere, most particularly blacks because their average IQ is so much lower than any other broad racial group. Such people will naturally resent being categorised as belonging to such a group, regardless of the fact that group IQ says nothing about the individual’s IQ (although a person’s race will increase the probability of what his or her IQ is likely to be.)

The ideologically committed nurturists should reflect on the implications of what they are saying. The only way mind could be divorced from natural selection is if it was not a product of biology. But of course that is not what the nurturists think, for they are generally materialists who are normally more than happy to accept that mind is simply a product of brain. Consequently, what the genetic determined IQ deniers are in effect saying is that natural selection does not operate on the brain, while they allow it operates on all other parts of not only Man but of the Natural World generally.

Interestingly, liberals have no problem with some genetic racial differences. For, example, sickle cell anaemia is happily acknowledged by liberals to be much more common in those of African ancestry and  DNA tests which can predict with a high degree of probability a person’s race pass without comment.

The reason why white liberals normally have, at least ostensibly, no problem with such genetic differences is twofold:(1) they do not say anything about the human being as a human being because they have nothing overtly to do with mind and (2) there is hard scientific evidence to say the differences exist – it would be literally absurd for a liberal to claim that sickle cell anaemia is not more prevalent in blacks.

There are other issues which are not so clear cut. A favourite argument of those who support the idea of racial difference in IQ is to invoke the claim that blacks are on average innately more gifted athletes than whites (there are considerable evidential difficulties with this claim and I examine the difficulties in appendix A “White men can run“) and hence it is not irrational or even unexpected to find other differences between races such as those uncovered by IQ testing. White liberals have a problem with this: they are torn between extolling an area of superiority for blacks and the realisation that if genetic superiority is conceded there the absolutist nurturist argument for IQ is weakened. This being so, they normally attempt to ignore the point, whilst allowing themselves to snigger in exquisite masochistic fashion about how “white men can‘t run“.

For those who are not hardline nurturists the question is how large a role genetics plays in IQ. Most psychologists who accept that there is a genetic component to IQ estimate it at anything between 40 per cent and 80 per cent. There are good reasons to believe it is at the upper end of those estimates, even plausibly above 80 per cent.

A child born in the most fortunate circumstances with every advantage of material advantage, health and education may have an IQ of 80: a child from the bottom of the social heap living without such advantages may have an IQ of 160. That this disparity between environment and IQ can happen – and of course it happens less dramatically all through the IQ distribution – points to IQ being largely genetically determined, perhaps even entirely determined by genetics, for why should high IQs be found amongst the poor and low IQs amongst the rich if this was not the case?

There are plenty of examples of men and women with little social advantage excelling in demanding jobs. Take the case of James Brindley. Brindley was the eighteenth century engineer who built the first great canal in England for the Duke of Bridgewater. The man was barely literate and came from a most unpromising background. Notwithstanding that he solved many utterly daunting engineering problems, problems which he had to solve from the bottom up because they were engineering challenges no one in England had previously solved. Clearly he was a man with a very healthy IQ, yet he had very little by way of education and none by social advantage. In fact many of the engineers of the Industrial Revolution were men of rudimentary education and poor backgrounds, men such as John Harrison the watch and clock maker and George Stephenson of railway fame.

The great variation of IQ amongst any population is in itself a powerful argument against IQ being wholly or largely culturally/environmentally determined. IQ is distributed within racial groups in a good approximation to the bell curve. Why should this be if the cultural/environmental element is dominant in determining IQ? Surely if it was dominant, the distribution of IQ would vary erratically according to the various circumstances of individuals, not merely differences in wealth but also the propensity of parents to drive children intellectually. Of course, there is a correlation between class and IQ but the average difference between the classes is not massive. The fact that such variability does exist and that the distribution of IQ (although not IQ scores) has remained broadly constant over the century in which it has been measured strongly suggests that  IQ is overwhelmingly determined by the genes.

That IQ distribution varies not only between the broad racial groups but within each racial population can be fitted into both the genetic and nuturist arguments. Sub-populations of the same race which are reasonably discrete would be expected to vary because natural selection would operate differentially on each sub-population, not least because societies will differ in the mental demands they place on their members. For instance, a genetic explanation for urban dwellers scoring better than rural dwellers could simply be that those who migrate to towns are both selecting themselves by making the decision to move (with the implication that they may be those with a higher IQ will self select themselves disproportionately) and then when they get to the town being further selected by their differentially successful breeding in their new circumstances.

More generally, if IQ is wholly or predominantly culturally determined, the sophistication of a society would be the cause of varying IQ distributions within and between races and any advance in social complexity would be not the result of increasing IQ but simply an emergent property of the organic structural development of a society, a Lamarkian rather than Darwinian process, that is, people would be able to do more intellectually demanding things because society demanded them and IQ would be improved. because they were forced to do them. (The Lamarkian anaology breaks down at the point of inheritance).

Although halfway plausible nuturist explanations can be produced for IQ differences generally, they cannot be found for racial differences. If IQ is predominantly the consequence of nurture it is very difficult to see how a nurturist explanation could be given for why racial IQ difference is, broadly speaking, stable regardless of the nature of the society in which a race lives. For example, why should South Koreans, who were living in a pre-industrial society until very recently, have a similar IQ profile to those of Korean parentage born and raised in the USA? There really is not any plausible non-genetic explanation for such uniformity. Indeed, it would be difficult to construct any nurturist argument, plausible or otherwise, to explain it because the differences of the two societies are so great. The best the nurturist could do is construct a wildly improbable scenario whereby different social pressures produced the same result.

If IQ was really radically changeable by improving social circumstances and by direct attempts to improve IQ test scores, the gains should be large not a few points, nor should they be seemingly temporary. Yet that is precisely what is found in the considerable number of attempts to bolster children’s IQ by placing those from poor families in materially and culturally superior circumstances. Even the gains claimed by the enthusiastic supporters of programmes such as Head Start in the USA (mostly in the range of 4-10 IQ points) are significant but not startling. Nor do the gains normally last but are subject to “fade out” after the initial uplift, until a few years down the line nothing is left of the improvement. Those who are interested in the detail of both attempts to raise IQ and sustain the improvement will find a review of the academic literature at chapter 17 of The Bell Curve.

It is also true that apparent gains in IQ from enhancement programmes occur at the lower end of the IQ distribution. Why is it that those who start with an IQ of 150 do not make similar gains to those with IQs of 90? The same applies to the “Flynn Effect” which charts apparent rises in IQ generally throughout the century in which IQ tests have been used. The overall IQ increases but most of the increase is found at the lower end of the IQ scale. The most probable explanations for the Flynn Effect is that whatever cultural bias that existed in earlier tests has been gradually squeezed out, secondary school education has become the norm at least in the West and the diet and health of the poor has radically improved.

It will be interesting to see whether the Flynn Effect continues in advanced countries now that the material circumstances of the vast majority of the population are sufficient to remove the possibility of inadequate diet or healthcare being one of the reasons for depressed IQ and the vast majority of people in such societies live in urban circumstances. (There are already some suggestions from Scandinavia – “A long term rise and recent decline in intelligence tests performance: the Flynn Effect in reverse” Teasdale and Owen – that the rise in IQ scores is diminishing or may even have already ended.)

Tellingly, the proportionate IQ differences between races have also remained broadly similar despite the “Flynn Effect”, The black psychologist Thomas Sowell has attempted to explain away the black/white difference by pointing out that ostensibly the black IQ scores of today are equivalent to the white scores of 50 years ago and by referring to the similar gap between whites from poor rural backgrounds and urban whites when IQs were measured fifty years ago. Sowell’s attempt fails because the black/white gap has proportionately remained as great. As black scores have risen, so have white scores. Consequently, it is difficult to see how the rise of black scores can be attributed to changes in culture or the environment. I emailed Prof Sowell and had this exchange with him:

“Dear Professor Sowell

I have come across your thesis that the black/white gap of one standard deviation is not abnormal there being other examples within a race, for example, between white rural communities and white urban communities. You also point out that black scores have risen over the past 50 years or so to that of whites of 50 years ago. “I see a problem with this argument: the black/white gap has remained the same over the period, i.e., white scores have improved proportionately. If the lower black IQ is only a cultural/environmental phenomenon, why should that be?”

Prof Sowell replied:

“As to changing IQs over time, James R. Flynn has written a number of things on that. As to how the black-white gap could remain the same if the difference is cultural, that seems less difficult to explain than substantial changes in IQ over time if IQs are hereditary. Incidentally, Professor Flynn has a book coming out on all this in the summer. The title doesn’t come to mind immediately but it will be published by Cambridge University Press.”

Frankly, his response to the problem is no answer at all. What the rise in  black and white scores does suggest is that the “Flynn Effect” either does not exist but rather is, as mentioned above, simply a product of the changing nature of IQ tests etc. – the modern concentration on culture-free tests could be responsible for almost all of the Flynn Effect IQ gain is on the visiospatial tests – or else all races are being subject to the same selective pressures which raise their IQs by a similar proportion, a proposition which is on the outer edges of improbability.

Finally, here is a commonsense reason to disbelieve the nurturist argument. If it was possible to radically improve IQ by changing the environment or through training, as sure as eggs are eggs the rich would have long ago availed them of such knowledge to ensure that their children had high IQs. The mass media and internet would be as full of adverts for IQ enhancement as for diets and cures for baldness. That this has not happened means there is no such magic IQ bullet or that at least no magic bullet which is known.

The primary evidence for some environmental influence is the fact that those from the same racial group tend to score less well on IQ tests if they come from a rural environment than those from urban environments, although that may be simply the consequence of inferior diet, healthcare and generally harsher physical conditions of life.

Personally I would be delighted if it could be shown that IQ is entirely or predominantly the result of nurture and could be enhanced through improving a person’s circumstances. Genetic engineering, surgery the use of cybernetics or drugs to enhance IQ is another matter, because they would almost certainly produce populations with radically different IQ distributions. This could be dangerous.

A population with IQs genetically or surgically enhanced to a high level – say, everyone had an IQ of 150 or better and the breadth of the IQ distribution was between 150 and 200 – could carry the seeds of its own destruction. After all who would do all the menial jobs in a society in which everyone had a healthy IQ? Would most people with such  high IQs even  are able to tolerate fewer menials but still relatively intellectually undemanding jobs such as technicians and junior white collar posts? A wide distribution of IQ is probably necessary for any human society to function.

 Cybernetic enhancement is less clear cut. It is possible to imagine a world in which people simply plugged into cybernetic intelligence boosters only when the person needed to perform higher functions. However, it is unlikely that cybernetic use would be restricted to such modest and utilitarian purposes. More probably, cybernetics would be used to permanently assist mental performance, not least because an individual would have to lead a schizophrenic existence otherwise: bright in one part of their lives, not so bright in another. A similar scenario would exist with drug enhancement.