I know of no data comparing the IQ’s of psychologists and mathematicians, so what I am about to say is pure conjecture and opinion based on my work in both subject areas. (I have doctorates in pure mathematics and in education, so I have a “skin in both games” and can make the claim that I’m unbiased.) I would guess that mathematicians, as a group, would significantly outperform psychologists on IQ tests. Of course, this is a generalization and does not apply at the individual level: there are probably some psychologists who would outperform many mathematicians in IQ tests and conversely. Yet, I have based my conjecture, in favor of mathematicians, on the fact that becoming a professional mathematician requires an IQ that is significantly higher than average. The IQ tests such as the Raven’s Progressive Matrices measure precisely the kinds of skills in pattern identification, problem solving, and generalization that are required in mathematics. It would be difficult for someone who could not do well on such IQ tests to perform well in mathematics. (The mathematicians with whom I worked in my doctoral studies were very high IQ people.)
Some branches of psychology, such as test theory do require mathematics and rigorous objective thinking, but the field of psychology has some specializations in which an exceptional capacity for abstract thinking and the search for disconfirming evidence is not paramount. This deficiency is evident in the lack of rigor in some research where unsubstantiated opinion and ideology sometimes substitute for objective scientific investigation. Some people who are below the level of very high IQ are attracted to such fields where doctorates are more easily acquired. Such people bring down the average IQ of psychologists taken as a group. Psychology is a very important field because it analyzes many concepts that are highly relevant to our lives, and I hope that we can encourage many of our best and brightest young people to enter this very exciting discipline!
