Muddying the waters

Nick Miller interviewed a pink-haired Jesse Prinz in a Manhattan cafe about a new book which the City University of New York philosopher has written challenging the supposed orthodoxy of genetic determinism. But the current consensus on the old nature versus nurture question is not genetic determinism: it is a view which recognizes the complex interactions between human genes and the environment. Prinz is also arguing against the idea that our brains are, as it were, primed for language. And he tries to undermine the credibility of the studies of identical twins which underlie current mainstream views.

There is something going on here. Such overweening intellectual ambition and contrarianism can't be driven solely by a dispassionate reassessment of the evidence. Fortunately, Professor Prinz is very upfront about the ideological motivations of his ideas. Like his CUNY colleague, Massimo Pigliucci, his intellectual work is inextricably bound up with his passionate commitment to progressive causes. The trouble is, mixing ideology and science is at best a distraction, a muddying of the waters, and at worst positively dangerous.

For his article, Miller also interviewed Geoffrey Miller of the University of New Mexico who effectively undermined the line which Prinz was taking by confirming what anyone with even a passing interest in these matters already knows: that studies of identical twins over the past two decades have demonstrated conclusively that virtually every aspect of personality is heritable (to a significant extent).

Steven Pinker, who has written on what he calls our language instinct as well as on broader issues of evolutionary psychology, is the most prominent public spokesman for the mainstream position which Prinz is setting out to attack. The following passage is from Pinker's book, The Blank Slate:

Identical twins, whether separated at birth or not, are eerily alike in just about any trait one can measure - verbal, mathematical and general intelligence, in their degree of life satisfaction, personality traits such as introversion, agreeableness, neuroticism, conscientiousness and openness to experience. They have similar attitudes towards controversial issues such as the death penalty, religion and modern music. They resemble each other in gambling, divorce, committing crimes, getting into accidents and watching television. They even boast dozens of shared idiosyncrasies such as giggling incessantly, giving interminable answers to simple questions, dipping buttered toast in coffee and writing indistinguishable syndicated advice columns.

If we want to improve our lives, the first step surely is to understand as best we can the situation we are in and this involves a recognition of the truly surprising power and influence of our genes.

Do genetic and environmental factors determine political orientation?

So often we see the truth of something, even talk or write about it, but don't fully realize the implications. And for me the implications of an idea which I have accepted for quite some time are finally, I think, sinking in. I'm talking about the idea that our - for want of a better word - ideological propensities (and perhaps values in general) are in large part determined by genetic and environmental factors.

Late last year and earlier this year there was a lot of publicity about a particular study (associated with the actor Colin Firth) concerning correlations between brain structure and political orientation. A paper detailing the results was published in April 2011 in Current Biology, and I had been meaning to have a close look at it, and perhaps to trace reactions and interpretations with a view to forming my own opinion on what it all might mean.

The study found that the gray matter volume of the anterior cingulate cortex was generally greater amongst university students identifying as liberal or left wing, while the right amygdala was larger in those who identified as conservative or right wing.

Predictably, a lot of nonsense was written by journalists and bloggers on the significance and implications of this piece of research - much of it along the lines that conservatives are less evolved!

It goes without saying that our knowledge of how brain structure and brain activity relate to thought and behavior is very limited. Research into these areas is at a very early stage and this study is a small piece of a very large and largely incomplete jigsaw puzzle. What the study does do, however, is to provide evidence that our political propensities are correlated to brain structures, which in itself is a profoundly important result. What it does not do is to validate value judgements about specific political propensities.

As the authors of the study point out, their research extends previous findings which related certain kinds of brain activity to political attitudes. Reference is also made to a study of twins which indicates that genetics plays a significant role in determining political views, and to other studies which have focused on the interaction between genetics and the social environment. "For example," the authors write, "political orientation in early adulthood is influenced by an interaction between a variant of a dopamine receptor gene linked with novelty seeking and an environmental factor of friendship."

Though not mentioned by the authors, research on birth order has thrown significant light on these issues. As I noted in a post last year, first-borns have been found to score higher on conservatism, conscientiousness and achievement orientation; later-borns on rebelliousness, openness and agreeableness. But, apparently, this pattern holds only within (rather than across) families because genetic effects are stronger than birth-order effects.

All in all, it is becoming increasingly clear that genetic and environmental factors play a big role in determining an individual's political orientation - and this is a hugely significant fact. When we engage in political (or similar kinds of) discussion and debate, we can no longer assume that we are dealing with people who - at least potentially - think like us. We all know from experience that such debate is usually (always?) futile, and at last, perhaps, we are beginning to understand why.

It is all very depressing for anyone who has been committed to the value of discussion and debate about values and politics. I want to face the implications of these findings head on. What consequences flow from them? Is ideological discussion a waste of time?

I'm still thinking about it.