Are Christians Less Intelligent Than Atheists?

Are Christians Less Intelligent Than Atheists? Here’s What All Those Studies REALLY Say

By Natasha Crain

Today I want to shed light on a nasty little “fact” that regularly makes the rounds online:

Studies show that Christians are less intelligent than atheists.

This statement is proudly tossed about by atheists who want to reinforce their claims that religion is for the poor, ignorant, and unintelligent.

And you know what? The statement is true…a number of studies have found a negative relationship between intelligence and religiousness (the more intelligent a person is, the less likely they are to be religious).

Does that mean people can legitimately say, based on these studies, that Christians are less intelligent than atheists? Absolutely not. 

I have an MBA in marketing and statistics and have taught university-level market research, so I’m a professional numbers geek…a numbers geek who dug into all these research studies to find out what they REALLY say. Today I want to set the record straight.

Before we get too far, however, I have to point out what is hopefully obvious: Even if we could reliably measure which group is smarter, the answer wouldn’t tell us anything about the truth of Christianity; intelligence doesn’t equate to always having the right answer.

Theoretically, we could end all conversations on this topic by pointing that out. But if your child asks you one day why Christians aren’t as smart as atheists, do you really just want to reply, “Well, that doesn’t mean Christianity isn’t true”? We owe it to our kids to be able to address the claim itself.

So here we go. Please bookmark this page as a resource that you can link to next time you see someone claim that Christians are less intelligent than atheists!

What 63 Studies on Intelligence and Religiousness Really Say

In 2013, researchers from the University of Rochester and Northeastern University pulled together all past studies conducted on the relationship between religiousness and intelligence at the individual (person) level. Of the 63 studies identified:

  • 35 showed a significant negative relationship between intelligence and religiousness (the more intelligent a person was, the less likely they were to be religious).
  • 2 showed a significant positive relationship between intelligence and religiousness (the more intelligent a person was, the more likely they were to be religious).
  • 26 showed no significant relationship between intelligence and religiousness.

In other words, only about half of the 63 studies suggest that the more intelligent a person is, the less likely they are to be religious. The other half of the studies don’t show that at all. The researchers themselves acknowledged, “The relation between intelligence and religiosity has been examined repeatedly, but so far there is no clear consensus on the direction and/or the magnitude of this association.”

First major takeaway: The common claim that studies have shown repeatedly that religious people are less intelligent is highly misleading. It ignores the results of almost half of the studies conducted. Overall, the results have been very inconclusive.

The goal of the researchers in 2013 was to look at these studies as a group for the first time, in order to better quantify the nature and magnitude of the relationship between intelligence and religiousness. Before we even look at the results, it’s important to note that combining 63 individual studies is very problematic. The studies varied extensively on:

  • Who was studied: Some studied precollege teens, some studied college students, and some studied noncollege adults (people recruited outside an academic context).
  • How many people were studied: Sample sizes ranged from 20 to more than 14,000.
  • When the studies were conducted: The studies were done over an 84-year span of time (the earliest study was conducted in 1928 and the most recent in 2012).
  • What the studies measured: Some studies measured religious behavior (for example, church attendance and/or participation in religious organizations) and some measured religious beliefs (for example, belief in God and the Bible).
  • How the studies measured: Twenty-three different types of tests were used to measure intelligence (for example, university entrance exams, vocabulary tests, scientific literacy tests, etc.). Details weren’t provided on how exactly each study measured religious behavior and beliefs, but that surely varied extensively as well.

Generally speaking, combining such disparate studies is a statistical disaster.

Cornell statistics professor William M. Briggs summarized the problem, saying, “Data of every flavor was observed, data that should not be mixed without an idea of how to combine the uncertainty inherent in each study and in how, say, kinds of IQ measurements map to other kinds of IQ measurements. In other words, they mixed data which should not be mixed, because nobody has any idea how to make these corrections.”

Methodological concerns aside, let’s pretend for a moment that it’s valid to combine the results of these 63 studies. Ultimately, there were two factors researchers found to be significant in the relationship between intelligence and religiousness. The first was the life stage of who they studied (precollege, college, or non-college). The second was the measure of religiousness(behavior or belief). The results suggested:

  • Religious behavior, such as church membership, has almost no relationship with intelligence at any life stage.
  • Religious belief has almost no relationship with intelligence in the precollege years (presumably because beliefs are more influenced by parents).
  • Religious belief has a very weak negative relationship with intelligence for college and noncollege adults (the higher the intelligence, the less likely a person is to have religious beliefs; the weak relationship is a -0.17 correlation between intelligence and religious beliefs for the college studies and a -0.20 correlation for the noncollege studies).

Second major takeaway: The results suggest a negative relationship specifically between intelligence and religious belief for adults, but the mathematical magnitude of that relationship is very small. Almost all variation in religious belief amongst individuals is explained by (unidentified) factors other than intelligence.

In review, here’s what you need to know next time you see someone make this claim:

Over the last 80+ years, many studies have been done on the relationship between intelligence and religiousness. In 2013, researchers pulled together all the ones that quantified that relationship. Of the 63 studies they identified, roughly half showed no relationship at all. The other half showed at least some kind of negative relationship (the more intelligent you are, the less likely you are to be religious). That said, statistically speaking, it’s not very helpful to simply know there is “some kind” of relationship. You have to know how strong the relationship is to know if it matters. Researchers combined the results of all these individual studies to evaluate that question overall and found the strength of relationship to be very weak.

What do I mean by very weak? A -.17 or -.20 correlation is considered to be a trivial or negligiblerelationship by most statisticians. In other words, hardly worth mentioning.

Now you have the whole story. But one last note. Please do not share the following article when you see an atheist make claims about Christians being less intelligent: Of 10 Highest IQ’s on earth, at least 8 are Theists, at least 6 are Christians. I regularly see Christians replying to atheists with that link and it makes me cringe every time. It doesn’t matter if the 50 or even 1000 most intelligent people on Earth are theists or Christians—that doesn’t statistically mean anything about the relative intelligence of Christians as a group. Engage instead on the studies underlying the atheists’ claims by sharing this analysis.

Any questions?

Are Christians Less Intelligent Than Atheists?

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33 replies
  1. Dakota says:

    I would flip the tables on the subject and do a study on the amount of apologetic information in reference to the Christian faith that the atheist has accumulated over time; more than likely they’ve merely learned a certain philosophy of knowledge through a post-modern worldview. How do you judge in this study with the curriculum being so vast? Certainly things are skewed. Can an atheist defend the facts of Jesus’ resurrection?

  2. Jason Klohs says:

    “Haughty eyes and a proud heart— the unplowed field of the wicked—produce sin.”
    ‭‭Proverbs‬ ‭21:4‬ ‭NIV‬‬

    This topic has been on my mind of late. Though I have the minimum of statistical training and conducted no actual studies, I metaphorically liken it to a rich man and a camel verse. It appears pride, like riches, are hard to keep properly prioritized.

    A man of faculty should be under control; “don’t need help!”. Surender to someone knowing truth other than what he “knows” to be true; no chance.

    I’m actually wouldn’t be surprised and might be a little disappointed if the population of Christians, as a whole, isn’t a bit lower on the IQ scale. Child like faith (trust) is a biblical quality encouraged by Jesus. Perhaps a little easier for the simple man than a free thinking person of reason.

  3. Neil Currie says:

    I am a practicing Roman Catholic with 5 university degrees including a Doctorate in Musical Arts from UBC (Vancouver) and a Maters in ClinicalPsychology, also from UBC. I believe because of what has been revealed to me.

  4. Randy says:

    How did they determine “intelligence”? Simply agreeing with and having more info in your brain is not a good thing if that info is false — such as evolution, global warming and such. To borrow and tweak a quote from Reagan: The trouble with our atheist friends is not that they’re ignorant. It’s just that they know so much that isn’t so.
    Wisdom is the true test — how well someone uses the knowledge they possess. Intelligence is knowing a tomato is a fruit. Wisdom is not putting it in a fruit salad. Given the gender confusion and political correctedness of the secular progressives today, wisdom is more necessary and seems to be in short supply.

    • Kyle says:

      I’d be extremely curious where you get this notion that evolution and global warming is false from. I was actually under the impression apologists understood and accepted both.

      • Louie says:

        You were under the wrong impression. Perhaps the world is warming, perhaps its cooling, and perhaps it isn’t stable and always changing. Either way, I am not convinced it is humans that are the culprit of the cooling or warming. If the data were a knockout punch, then we would not find instances of people manipulating it to push through an agenda. Evolution, same deal, when you have people that are taking bones and filing them down and trying create missing links, it does not help the case for evolution. I know we have some skeletons that show signs of evolution, but when you dig into them, and find out that the entire skeleton was generated from a tooth and toenail, it looses a lot of credibility. I find the world I live in is best explained by creation, not evolution.

        • Andy Ryan says:

          Louie, I think your view is shaped by you being unaware of the mountains of evidence for both Man-caused Climate Change and evolution. With the latter it’s not just about bones. Many biologists say that even if we had no bones/fossils at all, DNA evidence alone is sufficient to support evolution.

          As for ‘manipulated data’, you’re swallowing denialist propaganda.

          • Louie says:

            Andy, I think your view is shaped by you being unaware of the mountains of evidence for both Naturally-caused Climate Change and creation. With the latter it’s not just about bones. Many biologists say that even if we had no bones/fossils at all, the complexity of life alone is sufficient to support creation.

            As for ‘climate change data’, you’re swallowing agenda pushing propaganda.

          • Andy Ryan says:

            No Louie, I’m following the scientific consensus.

            “Many biologists say that even if we had no bones/fossils at all, the complexity of life alone is sufficient to support creation”

            If by ‘many’ you mean ‘a tiny proportion’, then sure. Could you name some of these biologists for me?

            “the mountains of evidence for both Naturally-caused Climate Change”

            Go ahead Louie and present some of this evidence to me.

        • Kyle says:

          There is no “perhaps” about the global temperature. It is warming. It is warming faster than it has ever done in the past that we know about. Yes there have been periods of warming and cooling in the past, but they were over much longer time periods. This is leading to climate change on a massive scale. The only instances of people manipulating the data in any way that I have seen has come from the denialist camp like oil companies and conservative politicians. The data is a knockout punch if you take your head out of the sand.

          Evolution isn’t just about bones and bone structure. LIke Andy said, “DNA evidence alone is sufficient to support evolution”. Check out the E. coli long-term evolution experiment from Michigan State University. They are literally watching evolution happen.

          There is tons of evidence to support both global warming/climate change or whatever you want to call it and evolution. All you’ve provided in rebuttal is you don’t like some of the evidence you have been presented from what we can only assume were denialists of both.

          What is your version of creation that you feel is a better explanation?

          • Louie says:

            I don’t have or need a version of creation any different than that of the biblical account. I’m sorry about the climate change nerve I have hit. Has the planet experienced warming? Sure it has. Has the planet experienced cooling? Sure it has. Will it continue to experience both? Sure it will. Will the rates of change differ? Sure they will. The planet is always changing temperatures, it is an awesome biological system. But to say man made CO2 is the culprit, sorry, not buying it. Temperature changes due to solar flares and volcanic eruptions and the like, yes, I am in. But to honestly believe that the man made 3% of the total 0.03% of CO2 in the atmospheric make up is to blame… Not buying it. And neither do many scientists, so now they are changing their minds and pointing to methane, since the CO2 thing didn’t take as well as they wanted. Then they’ll find something else after new technology spoils that theory. By that time, perhaps it will be cooling, and we’ll have to blame man for that as well.

          • Kyle says:

            Does your version of creation include 6 literal days? An earth that doesn’t move? Firmament? You seem to have absolutely missed the point of global warming. No one is denying that the earth has warmed and cooled in the past. The argument is that it is in a period of warming at a rate much faster than has ever been seen before. Unless you have some relevant background or degree you’ve been hiding, you “not buying it” means nothing. You have offered nothing to show that there are non-negligible amount of legitimate scientists that deny global warming. When over 97% of the scientific community agrees on this, you are on the wrong side. When institutions like the National Center for Science Education, headed by some of the most brilliant minds on this planet, flatly refute such notions that you are proffering, you are on the wrong side. When all your arguments stem from a complete lack of understanding of the issues, you are on the wrong side. Again, all we have heard from you is unsubstantiated claims and refutations that only demonstrate you do not understand the issues. Can we get something concrete from you?

  5. Andrew says:

    I have always thought if somebody is able to remember large volumes of data, recall it quickly, find correlations in large data sets but is constantly coming to the wrong conclusion, are they intelligent? Especially if they are coming to the wrong conclusion on life’s biggest questions.

    I love these verses

    1 Corinthians
    18 For the message of the cross is foolishness to those who are perishing, but to us who are being saved it is the power of God. 19 For it is written:

    “I will destroy the wisdom of the wise;
    the intelligence of the intelligent I will frustrate.”[c]
    20 Where is the wise person? Where is the teacher of the law? Where is the philosopher of this age? Has not God made foolish the wisdom of the world?

    I believe God really has made foolish the wisdom of the world. You have to daily wake and commit intellectual suicide over and over to believe that nothing made everything as opposed to something created everything.

  6. Larry erb says:

    Only a fool believes here is no God. Forget about iQ. Remarkably one of the most profound question every person has is, what happens to me after this body of mine dies? This question is ansewed unsatisfactory the most by an atheist.

    • Andy Ryan says:

      “This question is ansewed unsatisfactory the most by an atheist”

      You mean atheists give the answer you like the least?

      “Only a fool believes here is no God”

      Who says? The Bible. And how do you know the Bible is true? Because there is a God. And how do you know there is a God? Because only a fool wouldn’t believe there is one.

      Great circular argument!

      “Remarkably one of the most profound question every person has is, what happens to me after this body of mine dies?”

      Perhaps it’s more profound to concentrate on living a good life in the one life we KNOW we have.

      • Mark says:

        The word “fool” in the original Hebrew does not mean idiot, stupid, unintelligent, etc.

        It means “moral rebel.”

      • TGM says:

        That’s an interesting take Mark. And some quick research lends some credence to your notion. ‘Fool’ in some contexts was apparently an epithet as well. So if you are correct, I have to wonder why every bible translation shown on biblehub, including KJV, referring to psalm 14:1 (The fool says in his heart, “There is no God.”) uses the word ‘fool’. Why don’t any bible translations elect ‘rebel’ and instead say “The rebel says in his heart, ‘There is no God.'”?

        The word ‘fool’ has been in use since at least the 13th century, with older roots in French and Latin. And the word ‘rebel’, with similar roots, has been around at least as long. One would think the translators would have eventually worked this out and used the more appropriate term to reflect modern usage.

        So what gives? Well… ‘fool’ is a better word for rhetorical purposes. History is littered with great rebels, but not so many great fools. If I was looking to dissuade apostasy, I would probably address non-believers as ‘fools’ too. A nifty literary two-step and a fine example in the deceptive use of language by biblical scholars. More reason to distrust biblical authors & content. Nice work Mark.

        • Mark says:

          It is not my “take”, TGM.

          It is what the word means in the original Hebrew.

          And it does not mean “rebel”.

          It means “MORAL rebel”.

        • TGM says:

          Rebel or Moral rebel. It does not matter which phrase you use in the passage. The important question is why do all of the surveyed translations use the deceptive and inaccurate translation? You, yourself, are admitting they’ve all got it wrong. I’m happy to agree with you.

          • . Mark says:

            My point is simple: according to this verse, people who profess atheism are not dumb, stupid, unintelligent, etc.
            Rather, it is saying that SOME times SOME people’s motivation in denying the existence of God is to avoid moral accountability.
            That is all.

      • Richard Jude Woerner says:

        Andy asks, “And how do you know the Bible is true?”

        What theory of truth do you hold Andy?

        The next question is, is truth objective or subjective?

  7. Mark says:

    My point is simply this: this verse is not saying that atheists are foolish, dumb, unintelligent, etc. for not believing in God.
    Rather, it is saying that SOME times SOME people deny God’s existence in order to avoid moral accountability.

    That is all.

    • Andy Ryan says:

      “it is saying that SOME times SOME people deny God’s existence in order to avoid moral accountability”

      I’m not sure I see that meaning in the verse. Seems an odd thing to allege, anyway. If anything it seems the other way around to me – people quote a religious belief to EXCUSE bad behaviour rather. People can cite religion as a reason to refuse to serve someone or to keep slaves. There’s no atheist equivalent of that.

      • Mark says:

        Good point Andy. I suppose someone could say “God told me to kill you because you’re an infidel,” just as easily as they could say “There is no God, there is no heaven, and we may do as we wish.” Survivors of the Holocaust said the Nazi torturers in the camps said precisely the latter as they were beating their victims.

  8. says:

    Moral Rebels are foolish… To deny God is to deny hope, and a more optimistic outtake on life. It is wise to imagine that a holy God exists in order to be more motivated to be noble. I.e. if your dad is always there behind you, you act differently. God makes you think in a more personal “right vs. wrong” way, which leads to more positive social behavior.

  9. Narnian says:

    Studies show that people with tertiary qualifications are more likely to attend church. While the overall figure for a bachelor degree is 12% in Australia, Anglicans and Baptists are 34% and Catholics 22%. So church goers have 2-3 times higher education than average. What do you say to this?


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