Theres a study going around by Zuckerman, Silberman, and Hall that purports to show an inverse relationship between intelligence and religiosity. Heres the abstract.
A meta-analysis of 63 studies showed a significant negative association between intelligence and religiosity. The association was stronger for college students and the general population than for participants younger than college age; it was also stronger for religious beliefs than religious behavior. For college students and the general population, means of weighted and unweighted correlations between intelligence and the strength of religious beliefs ranged from −.20 to −.25 (mean r = −.24). Three possible interpretations were discussed. First, intelligent people are less likely to conform and, thus, are more likely to resist religious dogma. Second, intelligent people tend to adopt an analytic (as opposed to intuitive) thinking style, which has been shown to undermine religious beliefs. Third, several functions of religiosity, including compensatory control, self-regulation, self-enhancement, and secure attachment, are also conferred by intelligence. Intelligent people may therefore have less need for religious beliefs and practices.
After reading the paper, Im reasonably confident that they processed the data competently. However, Id add a fourth interpretation that they dont take seriously enough: that there was systematic bias in the intelligence studies they analyzed. Im actually personally put off (bias alert!) by any study that attempts to reduce something as complex as intelligence to a simple number amenable to statistical analysis. The various studies measure intelligence by GPA (grade point average), UEE (university entrance exams), Mensa membership, and Intelligence Quotient (IQ) tests. Can you say apples and oranges? Yeah, I thought so. And anyone who has spent any time with Mensa people knows they arent particularly shining examples of crystal clear analytical intelligence, for instance.
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Again, the statistics in the paper seem fine to my casual eye, but it really looks like a case of garbage in, garbage out. Im not at all impressed that we can discern a trend when the floor is defined by people willing to embrace racist bullshit.
I thought the attempts to explain the pattern were quite nice, addressing a number of different hypotheses, and some of them were reasonable in trying to find a broader cause than simply hicks is dumb. But I had a hard time getting past the implicit bias in the study that they were looking at intelligence. I dont think they were. I think you could find that ignorance is associated with religiosity a lot of religions oppose education and insist on keeping certain segments of the population (i.e., women) as uninformed and uneducated as possible, and just that fact is going to skew the results to fit their conclusion. They also note studies that show the higher echelons of academia and educated individuals are less likely to be religious, and I can honestly believe that analytical examination of the claims of religion leads to a loss of faith. But we typically associate intelligence with something intrinsic to the individual, a biological property of their brains, and nothing in this study allows that conclusion to be made. The word is heavily loaded and entirely inappropriate.
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Im more inclined to accept Gregory Pauls thesis that religiosity is coupled to socioeconomic status that if youre poor, youre less likely to get the education that would help you see beyond the delusions of faith, and that also youre going to be more reliant on the social safety net of your church. But its not lack of intelligence that is at the heart of religion, its class and emotional/cultural/historical concerns. Poor performance on IQ tests is simply a side-effect of discrimination and deprivation.
And, I must add, even if the correlation does hold up in studies that arent from racist jerks, its no consolation for you: your intelligence is a property of the individual, and being a member of statistically slightly superior group doesnt confer any special abilities on you, other than the ability to hide behind Richard Feynman and pretend his brilliance somehow rubbed off on you. It didnt, sorry.