To suggest that low belief in religion is due simply to high intelligence is to oversimplify a complex causation that includes, as all behaviour does, inherited and environmental factors. Among the latter is education, which is of course correlated with intelligence. In general, the higher the level of education, the less frequent and less dogmatic are religious beliefs. But intelligence cannot be the only factor, as there are significant differences between disciplines, with psychologists least religious of all (US figures). I would not suggest that we are more intelligent than our colleagues.
John Radford, Emeritus professor of psychology, University of East London.