While working on my previous article, Are you a Stupid Christian?, I realized I should probably address the actual scientific evidence regarding intelligence and belief. This was made all the more apparent when I came across some anti-scientific statements by several Christians on this very same topic (ironically, it was by people who lament the anti-intellectualism in the church). Ultimately, there’s no reason for Christians to fear this topic or be concerned with any science that seems to reflect poorly on Christianity and I will explain why this is the case.
Generally speaking, the scientific data reveals what many Christians fear: religious believers are not as intelligent as atheists. On average, they have less education, lower IQs, less scientific literacy, less verbal ability, and lower scores on analytical thinking (which means higher scores on intuitive thinking). On the one hand, most of the research does not distinguish between different religions so it may not reflect Christians. However, most of the research is done on primarily Christian populations and the few studies looking specifically at Christians have similar results. Therefore, it seems most reasonable to conclude that Christians, at least those in WEIRD (Western, Educated, Industrialized, Rich, and Democratic) countries, are less intelligent than atheists.
The first inclination for many Christians is to reject the science by trying to explain it away, but we don’t need to do this. For one, it makes us sound anti-science and anti-intellectual, which only confirms these results. Two, there are just too many studies from too many different areas (for example, scientists also tend to be more atheistic than the general population) which supports the same conclusion. This is called convergent validity and when present, especially with such high consensus, the results are pretty hard to refute. Finally, we can’t fix a problem we don’t think exists, so this type of research can actually help the church become stronger.
Let’s be honest, anyone who’s into apologetics has experienced extreme frustration with the rest of the church on this very issue. Why ignore this because perceived outsiders are saying what we’ve known is true since the First Great Awakening (late 1700s). The best approach is to embrace the science and take the time to understand what it actually means (and doesn’t mean) so that we overcome the issues.
The reason Christians initially feel the urge to reject this science is because it gives the sense that if Christians aren’t as smart, then we’re more likely to be fooled about our religious beliefs. While this could be true, there are a couple reasons I don’t think it is. On the one hand, it seems like smarter people are more likely to reach correct conclusions, but on the other hand, they are just as prone to bias, so they’re not necessarily better able to reach correct conclusions (see bias blind spot). The takeaway isn’t that we should ignore experts. I would still trust them over non-experts in almost all cases. Instead, we should carefully evaluate evidence and even question the experts on our own side.
The other reason comes down to understanding group data and effect sizes. When scores for a bunch of people are all averaged together, we can only make inferences about the group. So even though atheists as a group tend to be smarter, we don’t know if this is true for any particular person. Once we consider effect sizes (see chart), the problem becomes even more complex. Most of the studies have a small to medium effect size, which means there is a huge overlap between atheists and Christians on measures of IQ. In other words, if you choose an atheist and a Christian at random, it’s more likely the atheist will be smarter, but there will be a lot of times that the Christian will be smarter.
On a similar note, the difference in populations among groups means there are way more Christians or theists at every intelligence level than there are atheists. So if we were only to consider as valid the opinion of smart people or only people with a super high IQ, then Christians and theists would be in the majority and we should accept their opinion.
Finally, the differences between groups are pretty small. This means that the average atheist’s IQ is only a couple points more than the average Christian. If you met an atheist and a Christian with average intelligence for their group, you wouldn’t be able to tell who’s smarter without doing a series of rigorously controlled tests. So if someone wants to make the claim that Christians or theists are dumb, they need to make the same claim about non-theists.
While I maintain this research is valid and useful, it also doesn’t reveal a causal link, or at least the mechanism through which causality works. Religion could be causing people to turn off their brains, people with lower IQ may be more drawn to religion, more intelligent people may be more likely to disagree with cultural practices, and lots of other factors may explain the relationship (being a religious minority, personality factors such as openness to experience, lack of apologetics training, wealth, education, purpose, etc.), or some combination of these things.
In fact, much of the research uses education as a measure of intelligence. There’s a high correlation between education and IQ so this is a valid method that we have no reason to reject, especially because it helps at the individual level. For example, professional and aspiring apologists typically have substantially more education than the people they debate or argue with, which means in most of those cases, the Christian is likely the smarter person. This doesn’t mean the Christian is correct, but it shows that even if atheists are generally smarter, it’s not always the case.
I’ve spent my entire professional life working with highly educated people in academia or other research centers. Generally speaking, most of them are oblivious to the intellectual side of Christianity, including the smart Christians. I think it was Richard Dawkins who said that most of the scientists he knows don’t really even think about God even if they do believe (I’m trying to find the exact quote so if you know it, please let me know).
The fact that atheists tend to be a little smarter than religious believers is somewhere between irrelevant and a very very minor point in favor of atheism. I wouldn’t ever use this as an argument if I were an atheist because it doesn’t actually deal with the arguments, ignores the research showing intelligent people are just as biased, and shows a misunderstanding of what intelligence actually is. This claim lobbied against theists is just a distraction away from the content of the arguments, especially when considering that many intellectuals have never seriously investigated Christianity or sophisticated arguments for God (as opposed to dogmas or strawman arguments).
Thankfully, this is a problem that can be fixed. Intelligence is a composite of two factors, crystallized and fluid intelligence. Crystalized intelligence is our knowledge and it grows over the lifespan whereas fluid intelligence is our thinking ability and is generally stable over the lifespan. This means the church can educate believers, or at least encourage more education, which will lead to increased intelligence among believers.
As the church reconnects with its intellectual roots, it will also be more attractive to intelligent people. Incidentally, getting the church to engage more with their minds will help Christians be more well-rounded humans who are just as capable of loving God with their minds and they are with their hearts.
Apologetics is an obvious way to do this, but it’s not the only way. Encouraging deeper study of theology and biblical studies will also do the trick, as will studying science, philosophy, and the humanities.
“The heart of the discerning acquires knowledge, for the ears of the wise seek it out.” Proverbs 18:15
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