I've never quite wanted to go there . . .

But, it looks like we're there anyway so let's talk about it. You may have heard tell of this new paper in Psychological Science, the essential point of which is that lower IQ is associated with prejudice and conservative ideology. I've sorta kinda danced around this in discussing the prevalence of liberalism in academia and the canard about "liberal elites," but it isn't really a very good debate strategy to accuse your interlocutors of not being the brightest bulbs on the tree.

So let's cut to the chase. The association of lower cognitive ability with social conservatism, endorsement of intergroup inequality, and authoritarianism is well known. It is not by any means a new discovery. This is a fact: people with higher measured IQs and better grades in school are more likely to be liberal, tolerant of difference, and open to social change. The authors of this study cite plenty of research going back a decade or more.

What this study adds is actually fairly modest. Using large, longitudinal data sets, they found that British children with lower cognitive ability were more likely to grow up to be adults to be racists; and that this can be explained in large part by their having more endorsement of right-wing authoritarian ideology. A separate analysis of U.S. children had similar findings with regard to anti-homosexual prejudice. "In psychological terms, the relation between g [a hypothesized general intelligence] and prejudice may stem from the propensity of individuals with lower cognitive ability to endorse more right-wing conservative ideologies because such ideologies offer a psychological sense of stability and order."

Put more simply, confronting the real complexity of the world is taxing for many individuals. It is easier for them to contemplate the world in simplistic terms, while they are disturbed by diversity, disorder and change.

While I have no doubt of this, it does not seem to be a finding that can usefully be imported into political discourse. Telling people that they are stupid, or that their beliefs are a marker of limited intelligence, won't win you very many arguments. So I'm not sure what we can really do with this information.