Are We Getting Smarter? Rising IQ in the Twenty First Century.

Dutton, Edward

Are We Getting Smarter? Rising IQ in the Twenty First Century

James Flynn

Cambridge University Press. 2012

Political scientist James Flynn's 'Flynn Effect' has potentially huge implications. Highlighted by Flynn in 1984, the Flynn Effect refers to Flynn's observation that scores on Intelligence (IQ) tests in Western countries have been rising since at least the 1930s. On assorted different tests, when a new cohort has taken the test, they have scored significantly higher than the previous cohort. Thus, for the average IQ to remain at 100 (the benchmark by which IQ comparisons are made) the scoring of the test had to be adjusted. Flynn found that Western IQs have increased by an average of 3 points per decade since the 1930s. The biggest gains are on 'shapes' (as opposed to arithmetic or verbal reasoning), usually considered the most 'culture free' part of the test. This is the part of the test believed to be closest to g, the general intelligence factor on which verbal, non-verbal and spatial intelligence are thought to develop, and which is responsible for the positive correlations among these abilities. The implications of Flynn's finding, explored in this book, are dramatic. Modern society may be making us more intelligent. But more likely, because the gains are only dramatic on shapes and IQ test measures things other than intelligence, it is making us better able to think in an abstract way. This, as Flynn argues, should be a paralleled by more complex TV programmes, more sophisticated political debate, and, simply, an ever more complex society. And, he notes, if we're not aware of then we may even end up executing mentally retarded criminals due to their IQ being established on an out-of-date test.

In this new book, Flynn updates the body of research presented in his earlier book What is Intelligence? (Flynn, 2007), provides substantial appendices with all the relevant data, presents the nature of the Flynn effect in a clear manner with the educated layman in mind, and examines some sensational implications of failing to take the effect seriously. Most importantly, US states will not execute murderers if they are found to be 'retarded' (with an IQ of below 70). But if the prisoner's IQ test, whenever he took it, had not been revised for a long time then he might come out with an IQ higher than 70, even if his IQ were lower by today's norms, and so get executed. Flynn provides some surprising examples on the way in which the US justice system has executed people on the basis of higher IQ scores gained on highly questionable tests.

But, in general, there are serious problems with this book. Flynn ignores evidence that contradicts his theories. He cites the Dutch scholar Jelte Wicherts when discussing 'factorial invariance' of IQ tests. Flynn explains that this term refers to the way in which the three main forms of intelligence (verbal, non-verbal, spatial) have not risen at similar rates, as spatial (shapes) has risen much faster. But this is not what Wicherts argued. Wicherts claims that specific IQ tests given to different cohorts are not 'factorially invariant' over time, meaning they are not measuring exactly the same thing, and latent variables may explain the secular gains. This has the potential to render the tests incomparable and undermine the Flynn effect (Wicherts et al., 2004). Later, Flynn claims that there is no evidence that black-white differences in intelligence are genetic, but completely ignores interracial adoption studies (e.g. Weinberg et al., 1992; Frydman & Lynn, 1989; Winnick et al., 1975) and probability analyses (Levin, 2005, pp.125-126) strongly implying that they are.

For Flynn, 'intelligence' is not simply 'what IQ tests measure.' Intelligence is a general capacity to solve problems and absorb knowledge (p.7). IQ tests are very good at measuring this, but they are not perfect, meaning that other factors can contribute to a person's IQ score apart from their general intelligence. Flynn argues that the differential rise on different parts of the IQ test implies that it is not 'intelligence' that is rising, and thus, he suggests, g may no longer be that useful. He argues that we should instead concentrate on specific abilities which correlate with though are not entirely underpinned by g, as it is probably these that explain the Flynn effect. Flynn maintains that, since around the 1920s, we have increasingly donned 'scientific spectacles' by thinking in a more analytical way, and he gives some intriguing examples of how differently Russian peasants responded to analytical questions in the 1920s. Flynn suggests that this new way of thinking is exercising a specific part of the brain, making us better at certain kinds of thinking even if 'intelligence' is not rising or may even be declining.

However, he seems to go too far in suggesting that we should cease to focus on g. This is because it is 'intelligence' (g) which has predictive validity with regard to educational success, socio-economic success, law-abidingness and numerous other important issues. Flynn suggests that our 'scientific spectacles' have real world consequences, such as more complex TV programmes, but he can only really speculate on this and provides little solid data to prove that 'scientific spectacles' are more important than 'g.' Surprisingly, he does not take the opportunity to argue that technological progress over the last century can be explained by 'scientific spectacles,' though this seems to be implied.

Though one might commend this book for a refreshingly witty and personal style, it does appear to be rather emotionally motivated. Flynn seems to use fallacious and manipulative methods to win us round. Focussing on 'scientific spectacles' will 'break the steel chain of ideas' and if you are not persuaded to come on board then, 'I believe some feel that way, which is sad. They will always view the history of cognition through one window.' This 'one window' is 'g' and, as noted, Flynn suggests that 'scientific spectacles' are much more important than 'g,' a case that he does not appear to convincingly make because he does not show that 'scientific spectacles' are more important than 'g' in relation to life history.

Straw-man arguments abound. Flynn dismisses the hypothesis that cold environments selected in favour of intelligence by noting that some civilizations developed in hotter places before colder places. But nobody is suggesting that intelligence alone is behind the development of civilization; the question is whether there is a general trend for people evolved to colder climates (regardless of where they subsequently move to) to have higher intelligence. He dismisses the theory that better nutrition amongst the working class might explain part of the Flynn effect, noting that it would imply that their diet got worse around 2001--'What an up-and-down roller-coaster ride for the diet of the lower classes!' he mocks. But it is at least conceivable that this happened, as the rise in obesity attests.

Flynn rails against evidence that women have a slightly lower IQ than men arguing that the meta-analysis that proved this lumped together representative samples with convenience samples such as students. However, consulting the analysis in question reveals that it specifically ruled out convenience samples. This being so, Flynn's entire chapter trying to argue that women are more intelligent than men is speculative and has no foundation. Flynn finds two studies, from Argentina and Estonia, which back up his case, but the samples are not huge, he gives us no detail on gender differences on different parts of the test, and it contradicts two meta-analyses based on tests from all over the world (Irwing & Lynn, 2005, Lynn & Irwing, 2004) meaning it is not especially persuasive.

Flynn's style is also rather problematic. From the beginning, he seems to patronize his readers--'You must understand ...,' 'trust me . ..'. When unable to argue his case logically, he turns to rhetoric. This is best exemplified in the last paragraph. 'Read John Stuart Mill. When you suppress an idea you suppress every debate it may inspire for all time. Step forward those who believe they have the omniscience to censor the content of the intellectual history of humankind.' This kind of polemic is not conducive to the reasoned academic atmosphere necessary for the sharing of ideas and the improved understanding of 'intelligence' or anything else. This is a shame because Flynn is a man who, despite involvement in 'left-wing' political causes, risks provoking the fury of those very people with whom he sympathizes by defending IQ tests and highlighting -though not in this book--dysgenics (New Zealand Herald, 8 July 2007). Flynn seems to be passionate about creating a better public understanding of the 'Flynn Effect,' and hopefully he will at some point produce a more objective book that does just that.

References

Flynn, J. R. (2007) What is Intelligence? Beyond the Flynn Effect. Cambridge: Cambridge University Press.

Frydman, M. & Lynn, R. (1989) The intelligence of Korean children adopted in Belgium. Personality and Individual Differences, 10: 1323-1326.

Irwing, P. & Lynn, R. (2005) Sex differences in means and variability on the progressive matrices in university students: A meta-analysis. British Journal of Psychology, 96: 505-524.

Levin, M. (2005) Why Race Matters: Race Differences and What They Mean. Oakton, VA: New Century Foundation.

Lynn, R. & Irwing, P. (2004) Sex differences on the progressive matrices: A meta-analysis. Intelligence, 32: 481-498.

New Zealand Herald. (8 July 2007) Brainier mums needed to maintain future generations' intelligence, says professor.

Weinberg, R., Scarr, S. & Waldman, I. (1992) The Minnesota trans-racial adoption study: A follow-up of IQ test performance at adolescence. Intelligence, 16: 117-135.

Wicherts, J. M., Dolan, C. Hessen, D. et al. (2004) Are intelligence tests measurement invariant over time? Investigating the nature of the Flynn Effect. Intelligence, 32: 509-537.

Winnick, M., Meyer, K. & Harris, R. (1975) Malnutrition and environmental enrichment by early adoption. Science, 190: 1173-1175.

Dr. Edward Dutton's book Religion and Intelligence: An Evolutionary Analysis is published with the Ulster Institute for Social Research.