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When people discover that I am a Reader (Associate Professor) of Sociology at a school of social science they often ask me (or wonder to themselves, if they are more polite) how come I am doing what I am doing now? In other words, how did someone who started out in sociology (notorious for its bio-phobia and society-explains-everything dogma) end up proposing one of the most provocatively genetically-determinist theories: one about how, to quote the sub-title of my book, genes set the balance between autism and schizophrenia?
One of the most startling discoveries of modern longitudinal twin studies to which I have alluded before in these postings is that identical twins’ psychometrics—and IQ particularly—converge as they age. Indeed, a recent study of 11,000 twin pairs found that genes account for 41% of IQ in childhood, 55% in adolescence, and 66% in young adulthood. This is the exact opposite of what the sociologists would predict because it reveals that people do not show the cumulative effects of their environment, happenstance, and individual experiences as they get older. On the contrary, it suggests that as people age their genetic make-up becomes more prominent.
Furthermore, it figures if you think about it. For a start, younger organisms are inevitably more vulnerable to the environment and to disturbances in development than are older, mature ones. We can’t choose our parents, our early environment is inflicted on us, and brain maturation is not complete until the early 20s. However, the individual’s genome stays constant as the environment varies, and individuals usually seek out surroundings that suit their genetic endowment, thereby reinforcing its effect. We can select our friends and partners, and our adult life-style can often be mainly of our own choosing. People naturally gravitate to occupations, interests, and situations which they enjoy and feel they can succeed in, and in this way their genome shapes their later life in a way it seldom does their youth. In my own case, for example, I am convinced that more or less however I had started out—certainly in the academic world—I would have ended up doing something very similar to what (at the advanced age of 63) I am doing now.
Indeed, according to the imprinted brain theory, genes determine a lot more than IQ, and although the balance between what I would call mentalistic and mechanistic cognition is weakly affected by education, culture, and historical happenstance, its eventual configuration is likely to be mainly genetically-determined. In my case this effect was pretty striking, because nothing in my professional environment could possibly account for my eventual evolution into the originator of such a provocatively counter-cultural theory, however you interpret that term (and the culture of my profession certainly was contrary to my theory in just about every respect).
My personal constitution, on the other had, was more mechanistic—even somewhat autistic in certain respects. Indeed, I would certainly plead guilty to the charge of having an “extreme male brain.” (Although, according to the imprinted brain theory, this should more accurately be called an extreme paternal brain, it comes to much the same thing in the end and is certainly a major stigma in a profession whose dominant ideology is multi-cultural feminism and whose favourite scapegoat is the white male!). Inevitably I rebelled against the top-down, centrally-far-too-coherent holism of sociology and evolved a more factual, down-to-earth, bottom-up and reductionistic approach based on science rather than on ideology. This explains why I ended up as I did, doing what I am doing.
