New Study Says Atheists are Smarter Than Christians, but What Does That Mean?

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I felt a great disturbance in the Force, as if millions of Redditors suddenly cried out in ecstasy and then came in their pants. So I checked and yep, it’s a study saying that atheists are smarter than Christians. Time to jerk that circle, everybody!

As an atheist myself, I know I need to be very, very careful when talking about a study like this. Why? Because it’s really, really easy to believe anything that you want to be true. As much as I get annoyed by “organized” atheists, I gotta admit that if something is proving that either atheists are theists are smarter, I’m gonna hope it’s atheists. Because I am one.

And this isn’t like studies that might find that one race or one sex are smarter than another, because your religious outlook is malleable. It’s not based on unchanging genetics or biology we have no control over, really: it’s a conclusion you come to. So why wouldn’t I want scientists to tell me that the fact that I came to this particular conclusion means that I’m more likely to be smarter than someone who did not come to this conclusion? It would be like scientists finding that people who decide to dye their hair unnatural colors are more likely to be intelligent. Why yes, thank you, I agree with your scientific analysis.

But is the science sound? Let’s take a look at the data! 

First of all, this isn’t just one study — it’s a meta-analysis of 83 different studies that all looked at intelligence and religiosity. I’ve talked about this before: meta-analyses are great because they allow scientists to look at a large amount of data that shows us more of a scientific consensus on a subject, rather than just what one particular study may have found, which may be at odds with what 50 studies found prior. 

The trouble with meta-analyses is that you need to be very careful with what studies you choose to include and what studies you don’t include. Ideally, scientists pick and choose studies based on the quality of the data and relevance to the hypothesis being studied, but a less upstanding researcher could just cherrypick studies that find what they want to find, and ignore studies that contradict them.

In this case, Miron Zuckerman, a psychologist at University of Rochester, was really just building on a previous meta-analysis he conducted back in 2013. That one included 63 studies and also found a link between intelligence and (less) religiosity, but due to heavy skepticism in the media at the time, he wanted to either confirm or challenge his previous conclusions with an extra 20 studies that have been conducted since the initial meta-analysis. Sure enough, the new data mostly confirmed the early conclusion: people who were less religious tended to have higher intelligence.

One major issue with this meta-analysis is how they choose to define “religiosity” and “intelligence.” In this case, “religiosity” was defined by belief, not behavior: so if you believe in God but you don’t go to church every Sunday, you’re still defined by this meta-analysis as being religious. In the first analysis they looked at both and found that the correlation was stronger for belief, so in this one they stuck with that for consistency and, probably, to get the strongest possible result. Also note by “religious” they actually specifically mean “Christian,” as all these studies were conducted in Christian-majority populations. This meta-analysis says absolutely nothing about non-Christian religions.

Next, what do they mean by “intelligence?” That’s pretty much always going to be a sticky issue, because scientists are constantly improving how they measure “intelligence” and what it means, exactly. In this case, it absolutely does not mean “educated.” The results were the same for people with college degrees and those who had never attended college. Instead, the correlation works for people who took a variety of IQ tests, like Wordsum, a simple vocabulary test, and the Wechsler Adult Intelligence Scale, the most common IQ test in the world.

And can we say for sure that what these tests measure is “intelligence?” Well, yeah, but it is hard to say what that means for “intelligence” besides the recursive view that “intelligent” means “you were able to do well on this test.” And that’s one issue that Zucerkman points out in his meta-analysis: less religious people tended to have higher intelligence, but they also tended to be more analytical thinkers. He says that maybe intelligence tests are really just testing analytical thinking, as opposed to intuitive thinking, and so maybe all he is really saying is that religious people tend to not be as analytical as non-religious people, which isn’t nearly as fun a headline as “religious people are dumber than atheists.”

Also, it’s worth pointing out how big the effect is: not very. Don’t get me wrong, it’s a very clear, very strong result in that yes, there is little doubt that less religious people are more intelligent than religious people, but how much more intelligent? Not very. It’s so small, in fact, that scientists would not be able to predict intelligence based upon how religious a person is. Think of it like the difference between the height of men and women. American men are 5’9 on average, while women are 5’4. If I told you one person is 5’5 and another person is 5’7 you’d rightfully tell me you have no idea which is the man and which is the woman because the overlap is so large. The link between religiosity and intelligence is much, much smaller than that.

So with all that said, why are non-religious people ever so slightly more intelligent than religious people on average? This study doesn’t say, though Zuckerman has some guesses. He hypothesizes that perhaps religion offers benefits like raising your self-esteem, and giving you a better feeling of control over yourself and your circumstance, and more intelligent people already possess those things and so have no need for religion to give it to them.

Maybe! Or maybe the more analytical you are, the easier it is to see that the natural world has no need or even room for an all-powerful deity whether you want one or not. Because when I read Zuckerman’s conjecture, I realized that I absolutely could use some more self-esteem and feeling of control over myself and my environment. I spent a large portion of my early 20s wishing I could believe in a god because things were so much happier when I could imagine an afterlife for me and my loved ones. But I can’t, because it just makes no sense to me. It sounds like a fairytale. But maybe I’m just not smart enough to get all those benefits of intelligence and I just happen to be one of the dumber atheists dragging down the effect size for everyone else. Sorry, guys.

Rebecca Watson

Rebecca is a writer, speaker, YouTube personality, and unrepentant science nerd. In addition to founding and continuing to run Skepchick, she hosts Quiz-o-Tron, a monthly science-themed quiz show and podcast that pits comedians against nerds. There is an asteroid named in her honor. Twitter @rebeccawatson Mastodon Instagram @actuallyrebeccawatson TikTok @actuallyrebeccawatson YouTube @rebeccawatson BlueSky

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One Comment

  1. I forgive you for bringing down the effect size because A) you don’t bring it down nearly as much as some the atheists I work with, and, B) being an idiot doesn’t necessarily make you a bad person. :-)

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