Negative Correlation Between Religion and IQ

Friendly Atheist with a claim that researchers Have Once Again Found A Negative Correlation Between Religion and IQ.

By Hemant Mehta

Atheists love to pose this question as if the answer is meaningful: Is there a correlation between godlessness and intelligence?

Image via Shutterstock

It’s a silly question for a number of reasons. There are brilliant religious people; there are dumb atheists. “Intelligence” is a vague term and IQ is only one of many ways to measure it. How do you even accurately test such a thing? And supposed it were true: So what?

In 2013, a team of psychologists including Miron Zuckerman (of the University of Rochester) and Judith Hall (of Northeastern University) published a paper in Personality and Social Psychology Review that aggregated the results from 63 studies on the issue done between 1928 and 2012.

Their meta-analysis found that, yes, there was a “significant negative association between intelligence and religiosity.” Countries with a higher average IQ were found to be less religious.

While acknowledging the caveats, the researchers attributed that to the fact that intelligent people are less likely to conform and more analytical in their thinking — obstacles to traditional religion, no doubt — and less inclined to adopt religious behaviors.

In case you’re wondering, 53 of those 63 studies had that negative correlation, with 35 of them having a significant negative correlation. The other 10 showed a positive link (i.e. more intelligence was associated with more religiosity).

There were some reasons to be skeptical of the study, though. The 63 studies were all written in English (with a couple of translated ones), so they didn’t look at many studies conducted and published in foreign countries. Most participants were from the United States, U.K., and Canada — which are obviously dominated by Protestantism. In short, despite the number of studies, the researchers were looking at similar groups of people influenced by similar environments.

As you can imagine, there was a lot of controversy and discussion when that first report came out. And now Zuckerman and Hall are back at it, joined by Chen Li (of the University of Rochester) and Shengxin Lin (of the University of Chicago).

In a paper recently published in the Personality and Social Psychology Bulletin, they looked at 83 studies about religion and IQ — updating their data set with newer information — and found that religiosity and intelligence still have a negative correlation.

They included 61 of the studies they used last time, an additional 22 done between 2012 and 2018, and found that their 2013 results had not changed in any meaningful way. Zuckerman told PsyPost:

The evidence that there is a negative relation between intelligence and religiosity is very strong. But the effect size of the relation is small. This means that there are factors besides intelligence that explain why people are or are not religious. It also means that although more intelligent people tend to be less religious on the average, predicting religiosity from intelligence for individuals is fallible.

The new study is still heavy on Western countries (so Christianity is over-represented compared to Hinduism, Buddhism, or Islam), and there are still all those caveats about what intelligence actually means.

So I wouldn’t read too much into these numbers. I certainly wouldn’t get cocky about it. But if you were looking for evidence that intelligence and religiosity don’t always go together, this may be the most academic piece of evidence you’ll ever find.