Field of Science

Deep thinkers are more likely to lose their faith

There's always a fair amount of interest in whether atheists are more intelligent than believers. When I've reported on this in the past, I've always been a little sceptical about whether the purported statistical association is meaningful or even real. SO here's a couple of studies that shed an intriguing light on the problem.

The first by psychologists Gary Lewis, Stuart Ritchie, and Timothy Bates at the University of Edinburgh in Scotland has provided some of the most rigorous evidence to date that the link is indeed real. They took data from the large MacArthur Foundation Survey of Midlife Development in the United States and found that high IQ was significantly associated with every one of six different measures of religion.

For the most part, this association still held even after adjusting for factors like education, sex, age and even personality - the only exception with spirituality, the weakest of all indicators of religion. Overall, link between religion and IQ was strongest for the 'fundamentalism' measure.

The authors point out that the effect is very small. And what's more, there's still no reason to suppose that atheists are less religious because of their intelligence. There might be some other factor that they didn't account for that's related to both.

And that's where the second new analysis comes in. Led by Amitai Shenhav, a psychologist at Harvard University, the team looked at cognitive style. Basically, they were interested in whether people make snap decisions based on their gut feelings, or whether they ponder things a bit more deeply.

So they asked the questions like this:

“A bat and a ball cost $1.10 in total. The bat costs $1.00 more than the ball. How much does the ball cost?”

The intuitive answer (10 cents) is the wrong one. Stop and think about it for a while and you'll figure it out! You'll probably take less time than I did...

Anyway, it turned out that intuitive thinkers (who get the wrong answer) are more likely to believe in god and immortal souls. Even more intriguingly, deep-thinkers were also more likely to say that they had lost their belief since childhood.

That seems to fit with other research showing that believers in the paranormal seem to have a bunch of faulty, intuitive beliefs about how the world works.

But maybe you're thinking this isn't really about IQ? Maybe the religious just couldn't figure out the right answers (it took me quite a lot of puzzling before I figured that example question out).

Well, in one study they did measure IQ, and IQ was indeed correlated with 'thinking style' test scores. That means that cleverer people were more likely to get the answer right.

However, even after adjusting for their higher IQ, deep-thinkers were still more likely to be atheists, and to have lost their childhood religion.

Now, you can probably invent explanations for that just as well as anyone. But one implication, it seems to me, is that this might help to explain the apparent link between atheism and IQ.

You see, if cognitive style and IQ are linked, then it might be that IQ is an innocent bystander here - a case of guilt by association. How you think, and whether you take the time to ponder things through, might be all that matters.

ResearchBlogging.orgLewis, G., Ritchie, S., & Bates, T. (2011). The relationship between intelligence and multiple domains of religious belief: Evidence from a large adult US sample Intelligence DOI: 10.1016/j.intell.2011.08.002

Shenhav A, Rand DG, & Greene JD (2011). Divine intuition: Cognitive style influences belief in God. Journal of experimental psychology. General PMID: 21928924

Creative Commons License This article by Tom Rees was first published on Epiphenom. It is licensed under Creative Commons.


  1. "The intuitive answer ($1.00) is the wrong one.

    I think you might have meant "The intuitive answer (10 cents) is the wrong one...

    But interesting post though. And it goes to show I'm not such a deep thinker after all.

  2. And, while correcting the $1.00/10 cents slip, you might look also at "there's still no reason to suppose that atheists are more intelligent because of their intelligence" . . .

    Many thanks for Epiphenom, despite the (rare) typos: it offers some of the best reading on the interwebs, and I recommend it widely.

  3. Well you know the only reason I insert these is to check if anyone is actually reading any of it :) Heh - OK but thanks - all fixed now!

  4. Tom, great post. Thanx

    My son is 11-years-old and in advanced math. Even he fell for the problem in your post. I, on the other hand, got it very quickly without reading ahead.

    Kids live off their intuitions and we try to train them to stop and think! Thus, childhood is a perfect time to get people into a religion. But those kids who become religious and who think deeply will eventually be tormented later in life with the cognitive dissonance. They must then make some sacrifice.

    I use to be a believer (due to superstitious intuitions) and later (over a few years) started to think "too" deeply. In fact your post inspired me to write a post on that today). I hope my son keeps developing the ability to think too deeply before someone tries to use his false intuitions against him.

  5. This is a really interesting take on the study - I enjoyed the read.

    Now here's where I got a bit uncomfortable: I remember reading an article about intuition in problem solving - I believe this was a 'GEO' article, which is the German equivalent to 'National Geographics'. They tested how well people could choose the best option out of about eight different products using (a) their head (=they were given time to think about the problem) or (b) intuition (=they had to decide quickly). The finding was that for decision with few variables, I believe up to around four, the 'thinkers' came out ahead, but when a few more variables were brought in the 'intuiters' made the better decisions.

    The conclusion was basically: simple problem - use your head; complicated problem - trust your intuition. While the '$1.10-problem' is quite simple, questions about the ultimate purpose of being are rather complicated. This would suggest that the 'intuiters', i.e. the religous, might have come to the more accurate conclusion!

    I am, by the way, a 'thinker' and complete non-believer.

    PS: I found an announcement for that particular issue of 'GEO' (May 2010) here.

  6. I guess it depends on what you mean by 'best'. I've seen studies where if you give people a lot of choices and a lot of time to think about them, thytend to be less satisfied with the choice they make - perhaps because they've had time think about how wonderful all the other options were that they turned down.

    Also seen studies on home buying. Making lists of pros and cons actually makes it harder to make a decision you're happy with. You're better off just walking into the place and going with your gut feeling.

    But these subjective decisions are a different proposition to trying to ascertain an external, objective truth. After all, if gut instinct was a reliable guide to reality we would have no need for all those pesky scientists!

  7. Well said, Tom.
    Also, Intuition can be trained. Build skills until they become reflexive and the become new intuitions. So a trained persons "intuitions" are very different from a naive person's intuition which relies on inborn good-enough-to-reproduce heuristics.

  8. Sabio, that seems to be what Malcolm Gladwell was saying with Blink: Than intuitions of an untrained person isn't that special, but the intuitions of an expert with years upon years of experience was pretty darn good.

  9. This reminds of a study that found a strong correlation between how much anxiety expression over errors and religious belief.

  10. Sorry, but I just don't get the $1.10 / 10c thing at all, what am I missing >_<

    I work with money all the time, how does that question work? This is driving me crazy :(

  11. ball=a

  12. Yeah, I had to explain it to my wife and son twice.
    The numbers without the algebra helped:
    ball + bat = $1.10
    If ball = .10 then bat = $1.10, total = $1.20 (wrong)
    If ball = 0.5 then bat = $1.05, total = $1.10 (right!)

  13. The bat + ball problem is very simple if you think visually: the bat is $1 more, so you put the "more" bit to one side, then divide the rest into two equal "portions". A lot of logical puzzles stop being puzzling if you think visually :)


  14. Thanks for an interesting article, though I'm left wondering if I'm a paradox.

    I couldn't figure out why your 'intuitive' answer was wrong until I read the comments and then had a 'DUH' moment!

    I'm also an atheist who only lost his childhood religious beliefs in his late 40s.

    I guess I'm one of a tiny elite of very thick atheists ... ;)

  15. Well I'm with you in that elite. When I first read the puzzle (in the press release) I assumed the idiot press officer must've made a mistake. Only when I read it in the paper and spent some time pondering it did I figure it out. I'm not very good with trick questions!

  16. @ Anony:
    Take heart. Like many studies, we often just hear of a statistical significant difference between groups but little of the magnitude of the effect. If the sample size is large enough, Atheists may only have 0.05% more deep thinkers than those religious folks (whatever subgroup that was). Thus, Atheists who walk away from this study using it as a talking point may be deceiving themselves concerning its real significance. In medicine we differentiate these things by calling one "clinical significance" and the other "statistical significance".

    Besides, lots of atheists leave their faith not because they thought deeply because it made them feel more comfortable divorcing their spouse, to stop wasting Sundays when they could be golfing, or maybe something more virtuous like just getting fed up with hypocrisy about them. Those folks may do that without looking at all into theology, philosophy or any such thing. Hell, they just know it ain't for them.

    Blogging Atheists, on the other hand, may be disproportiate in the "deep thinking" category while they may also be disproportionate on certain personality disorders too. :-)

    So don't feel bad about this research.
    :-) Hopefully you see that this was written with 1/3 sarcasm but I am not sure if that is a statistically significant amount of sarcasm.

  17. Tom,
    You should turn off the ability to post here as "anonymous". It makes it so hard to address each other specifically.

  18. Do we all start with the intuitive answer?

    In other words, did any of you get straight to the correct answer without being aware there's a trap?

  19. @Tom: At least you did figure it out! There are some kinds of puzzles I'm not much good at, either (this kind, apparently!). Though I am rather good at - even if I say so myself - puzzles like sudoku, and the more fiendish the better!

    @Sabio: Interesting points on significance, though in my case it may well still be more 'statistical' than 'clinical', as it took almost fifty years until I realised my foolishness ...


  20. I was raised Catholic but was losing my faith growing up - I did think a lot about it and couldn't understand things like how Jesus could be God yet also God's his father - if there's only 1 God, and if God's not a "Species" or anything... etc. I didn't want to be confirmed Catholic at age 14. But I also had the influence of being exposed to differing beliefs including my father being raised Jewish and being agnostic and my brother's best friend being stuck in Jehovah's Witness family, etc. I like to think I was a deep thinker... but that probably about the bat and ball costing $1.10 I could not figure out. Granted I used to be better at math and now I think I just give up too easily. I maybe would have figure it out if I tried harder and actually wrote something down or drew a picture or something. :P

    But I don't know.

  21. I am actually astonished about the number of people that couldn't figure it out... But I guess I might have senn the puzzle before somewhere, so I fell out of this trap rather quickly.
    How about that: if people have inaccurate STARTING information, they can deduce a perfectly logical conclusion that is actually wrong. Given that supernatural thinking is kind of learned (your other post), this is convincing evidence that religious indoctrination should be fought with... Children rely on copying their parents' behaviours, even if they are bull faeces ;). Now I'm not saying that some kind of total control should be introduced, but that critical thinking should be taugh even in kindergarten. That's a way of prevention.

  22. Hey all, Here's another take for you. :) I'm a (hopefully) deep thinker who grew up atheist and is now deeply religious (since my late twenties). And i got the bat/ball pretty quickly. :) I think tho that the definition of 'deep thinker' requires some work....

  23. Emily, this is easy to clear up: Jèsu was the son of man; Emmanuèl was the son of god (well, of gods logho and pneýma); the latter dwelt in the former. Both Testaments along with their commentaries come with at least 18 gods, good and bad, wer and wif, old and new, folk and walsh, under many guises and long-forgotten today.

  24. Tbh I don't think that measures how deeply someone thinks in general. Maths for me is something I am very competitive at so I always try and get answers quickest, and it's just natural instinct u can't stop the answer forming in your brain. In everyday life and issues however I really think and consider, I don't think my competitive maths attitude should mean that I'm not a deep thinker. Maybe whoever does the study should or does use a wider variety of questions to access how deep someone is on different levels.

  25. Don't see the real link, I'll spell it out but don't be too quick to label my worth.

    The trained mind is able to stop and inspect the 'problem' with objectivity used in the bat/ball problem in an analytical way and discover that they are being misled.

    This mind has only trust in science, reason and self. It is quicker to formulate algebraic equation instead of simple subtraction.

    The Trusting mind has yet to be misled and is easily trapped.

    The link is higher-education, we're turning atheists out of every area of study and they are much smarter at not being tricked into playing the game with that mean old god.

  26. Sorry I'm late to the party here, I just came across this post. It seems on the face it it odd that we even ask this question of whether IQ is correlated with religious belief vs. non-belief.

    The very idea of it seems to assume that religous belief in general is simply some sort of blatant problem solving error that should be picked up by more efficiently holding the right information in mind at the same time. I guess I've come to think of that as way off base, and religious belief as a result of a specific kind of cognitive schema rather than an outright error that would be recognized with greater ability to handle complexity.

    Still, since we have asked the question, now we've gotten a small but real effect to explain.

    To me the fact that the effect increases with the arbitrariness of the belief seems to tell us as much about the range of religious beliefs as it does about what is unique about religion.

    I would expect intelligence and reflectiveness to also be correlated with the arbitariness of other (non-religious) kinds of beliefs as well. That is, just as we have a variance from spiritual beliefs (high affect, low doctrinaire arbitrariness) to "fundamentalism" (low affect, high doctrinaire arbitrariness) might be not have a variation in beliefs about nature that range from less to more doctrinaire?

    Has this comparison been done to your knowledge?

  27. Why should a person be considered less intelligent because they are religious? Figuring out that the answer is 5 cents only after knowing that the answer is not 10 cents. Why does the answer have to be 5 cents, why can't it be 10 cents? Think about it, you assume the answer is wrong because someone told you....... Why can't it be right? Something to ponder?

  28. “A bat and a ball cost $1.10 in total. The bat costs $1.00 more than the ball. How much does the ball cost?”

    I see no other answer but 10 cents so I am assuming it was a typo because logically it can't be any other answer unless we want to throw in David Hume's philosophy or say that we are merely using "play money" or change the meanings of "ball" and "bat" as code for something totally different and then say "gotcha". I am an Atheist and I am a former Christian. There are plenty of smart Christians out there, but there are far more less intelligent Christians than there are really smart Christians(the smart Christians usually let there mind sleep under the guise of being obedient to "the lord" since questioning the Bible is allowed but only through lip service. We aren't supposed to judge the Bible and call a contradiction a contradiction, it is supposed to judge us. I am such a deep thinker that I intimidate people without meaning to. I have been condemned by tons of religious people telling me that my intellect is my worst enemy, then they lay on the guilt trip. I explained my deterministic view of reality which proves to my satisfaction that a deity CAN'T exist(unless a person was talking about Deism) to a seemingly smart Christian friend of mine at school and he couldn't wrap his mind around it. I explained how self will is an illusion, cut and dried, simple and straight forward. Thinking about "the will of god" or whatever always looked to me to be SCARY, I needed to understand it and figure it out. I think at the end of the day, if a person is not intelligent, they most likely won't become an Atheist. The smarter a person is the odds of them becoming an Atheist go up. In other words, being brilliant is not going to automatically turn a person Atheist, but a high IQ almost seems a pre-requisite to becoming an Atheist.

  29. One other thing now that I think about it. Was "the intuitive answer is the wrong one" referring here to 10 cents, was a blatant logic fallacy like it being done on purpose to see who was a follower and who was independent? Same type of thing as if a person saw a contradiction in the Bible, they are merely mindless sheep(either by lack of intelligence or by choice) and their pastor and friends ALL deny the blatant contradiction and explain it away using irrational explanations that are insulting and patronizing, so the good little sheep agrees with the group think despite knowing the right answer. You tell people that the obvious right answer is not the right answer(even though it is) and then see who agrees with you. If that is the case then you are correct in one respect, the intuitive answer is not the right answer because it was a test for gullibility as opposed to independence.

  30. @David: That was a lot of text to demonstrate that you didn't read the post, didn't understand the problem and didn't find the correct answer; I'll just copy Sabio Lantz's answer from above (with a fixed typo):
    The numbers without the algebra helped:
    ball + bat = $1.10
    If ball = .10 then bat = $1.10, total = $1.20 (wrong)
    If ball = 0.05 then bat = $1.05, total = $1.10 (right!)

  31. David: You are a dolt. $1.00 does not mean $1.00 more than, there are no illusions but delusions, a person is not a they, and every keystroke is a týpo but a misstroke is a dýstýpo.

  32. If you really want to get deep, you could talk about how David Hume would speak about this kind of question. Better yet, how would Quantum Psychology approach this? ANY equation exists ONLY in my mind, as a function of my central nervous system, therefore, ALL answers are wrong since they don't really exist. The answer may be correct now, it may have been correct for the entirety of time that the "rules" that make up the math behind the equation have existed, but that doesn't mean that next time the rules won't change since we haven't experienced eternity, only the here and now.

  33. athiests want to be 'free thinkers' they want to know that they are not following tradition blindly; which is their skewed stance on religion. In fact, i am not sure whether anyone realises this but it is ridiculously more difficult to be a catholic in this world than it is to be atheist.
    There is so much of a majority of non religious people; and so much hatred and anger that is pointed at religious people from the media as well as society, that infact to say that most religious people follow religion without having thought through is presumptuous... why would anyone 'go along' with being continually shot down?
    Consequently i think it is so very much easier for people to lose their religion due to pressure from society than it is for people to follow a religion due to tradition. Perhaps it is this cohort that is not using their brains..but going along with the majority as to avoid judgement from others of being a 'nutty religious'?

  34. "Deep thinking" is a kind of misnomer here. In cognitive psychology, it has become accepted to distinguish two systems of thinking, System 2 analytic, working memory analysis, correlates with IQ and System 1 a large and open array of thought processes about which little is known, that involves unconscious processes and conscious outcomes, and relies on both innate thought and the accumulated conclusions of a lifetime of experiences.
    The distinction is presented in Nobel laureate Kahneman's recent book. The task in question (bottle and cap) is part of a quick and dirty method to assess System 2 processing.
    Hard to say which is deeper. Harder yet to determine which is the way to go, when coming to an entire worldview. To allow System 2 to get a handle on the issue, one must basically reduce the question of belief in God to something akin to a scientific hypothesis, and some religious folks do endorse this approach. To me, this is a kind of secular version of what religion is about.

  35. It's a fair point to make that neither system should be considered to be 'better'. They each have pros and cons, depending on the situation.

    Another point is that it may simply be that, culturally, these subjects associated analytical thinking with non-religion, and intuitive thinking with non-religion. So when they are primed accordingly, they shift their responses.

  36. You error - and that of the rather simple study - is hypothesising (unconsciously, obviously) that the relationship is linear.

    We encourage (and teach) analytical thinking skills. Those who are good at it score highly on tests for g, the general measure of intelligence.

    We do not enable people to learn how to use their intuition and emotions to evaluate situations. These pattern recognition processes are what enable us to live, to walk, see and be without ever having to resort to our pathetic analytical thinking skills.

    Once you're intelligent enough (in a far deeper sense than analytically) to realise that, you develop wisdom.

    And once you develop genuine wisdom you are open to possibilities our puny intellects dismiss.

    Go to thy bosom, knock, and ask they heart what it doth know.

    Clever people will point out the heart is a pump and know nothing. Wise people are with Shakespeare on the matter.

  37. This study changes not a thing.

    Intelligence is a person's capacity to (1) acquire knowledge (i.e. learn and understand), (2) apply knowledge (solve problems), and (3) engage in abstract reasoning. It is the power of one's intellect, and as such is clearly a very important aspect of one's overall well-being. Psychologists have attempted to measure it for well over a century.

    Intelligence Quotient (IQ) is the score you get on an intelligence test. Originally, it was a quotient (a ratio): IQ= MA/CA x 100 [MA is mental age, CA is chronological age]. Today, scores are calibrated against norms of actual population scores.

    Now this is why I think assuming that people with high IQ will not be believers is wrong: 1: acquire knowledge capacity--how fast you acquire knowledge.

    Everything past that besides an increase in ability to understand what you are working with is nothing special.

    Apply knowledge capacity--if you do not know how to make use of the knowledge, then you do not have the knowledge to make the most out of the current knowledge you have. Abstract reasoning--using what you know as reference to come a conclusion about what has not yet technically been applied. In other words reasoning: "a" applied to "b" produced "c". So based on what I know about "a, b, and c", "a" combined with "g" should produce "k". You are still using what you already know, what you have witnessed in "real-time" to deduce what is not occurring in "real-time".

    So to sum it up, all a high IQ really deals with is how fast you learn things and helps to have a good memory otherwise that doesn't do much for you in the long run. Even with understanding: many people did not get the baseball and bat question, however, once it was explained to them they now do. Furthermore, they know why and how. In the future, they will refer to the lesson learned. Pace of learning different, the IQ whiz's brains put things together a bit faster, but they still learned in due time. The answer to the question remains unchanged, as is the reason why the answer is correct--unchanged. So this is insinuating basically that once you reach a certain knowledge level then you realize there is no God. The reason why children who have high IQ realize this sooner is because they learn faster and so reach this amount of knowledge on the subject sooner.

    However, all that is saying is that based on the evidence there must be no God. In other words there is still a possibility of new evidence being presented to prove that there is a God. This is not to say you should go "well that means distrust all reasoning for fear of new evidence changing everything". No, human beings because we cannot see the future (for the future never ends) have no choice but to use what we know in order to live and make decisions. If you have no reason to believe in God, you shouldn't. What I am saying is if you reach that point where God seems like God is not real, you have an option to keep looking for evidence in the other direction if God means that much to you; you may find it BECAUSE the future is no written in stone. Doesn't take much abstract reasoning to come to that conclusion.

  38. Finally, four more things that effect people even with high IQ: level of sanity, emotional limiters, whether or not you choose to believe certain information even after it is proven with all your logic that is is true (you can still deny it and alter your perception of what you already knew just so you do not have to accept it), and finally definition. We say God, which god? Buddha, New Ageism, Christian, some Pagan God? Cthulhu? Is it a person, an animal? A mass of energy? An infinitely powerful bowel of Ramen noodles? A giant egg with a chicken's head and appendages? You, the person, define God--not a book, not your friend, not science, you. Then you decide whether you want to believe in God, and whether you give up on God in the future. God is a name, what that name means is up to you. Maturity to me: knowing who you are and taking full ownership of your life and your choices. High IQ does not equate to maturity.

    In conclusion: this study was just another waste of the time in the scientific community that changes nothing.

  39. You grow up as a child with a high IQ, when you become an adult you have to learn that your IQ does not define you, YOU are you and you must USE your IQ--determine how you will apply the applier and that actually depends on intuition. If you don't care about life, chances are even though you may know all there is to know about everything--you won't do jack. Because you do not care, the intuitive response of "this is important to you" is not present. Intuition/Instinct (as they go hand in hand) can in fact be manipulated with consciously willed logic, even reprogrammed with given time. But if you cut it out completely you have no instincts, no drive, no greater sense of purpose. I've seen a lot of smart people revealed to be indecisive--when given multiple equal answers to a question their stress eats at them. Cowardly--they live in fear of being wrong, and so eventually start limiting their own movement and constantly under stress. That stress prolonged starts effecting their ability to think and before long they crumble whereas if they said "I can be wrong sometimes, that is okay". They'd be wrong less in the long run. Childish--they say "I must", "I had no choice", "I need", "I can't". No, it should be "I will", "I will not", "I want", "I have a choice", "I can". It should be "I'm right as far as I know, and that is enough, what is important is do I know enough to get what I want done?" It should be when given equal answers to which you have no stronger preference..."this is an opportunity to add a new dimension to me, so who do I want to be?"--preference gained.


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