Religion and Intelligence

By Vexen Crabtree 2007

Like this page:

Share this page:

#anti-religion #astronomy #atheism #belief #buddhism #christianity #education #god #intelligence #japan #korea,_south #religion #science #singapore #stupidity #taoism #theism #UK #USA

The historical battles between religious institutions and science, such as those in physics, astronomy and biology, indicate there is something wrong with the religious approach to the study of reality. The underlying problem extends to negative effects on the individual intelligence of believers, and a related negative effect on educational achievements. Hardly any of the several-hundred Nobel Prize winning scientists have been Christians. Only 3.3% of the Members of the Royal Society in the UK and 7% the National Academy of Sciences in the USA, believe in a personal God. The more senior and learnéd the scientist, the less likely they are to believe in God. The children of highly religious parents suffer diminished IQs - averaging 7 to 10 points lower compared to their non-religious counterparts in similar socio-economic groups. As you would expect from these results, multiple studies have also shown that IQ is opposed to the strength of religious belief. 39 studies since 1927 (out of 43) have found that the more educated a person is, and the higher one's intelligence, the less likely someone is to hold religious beliefs - "religion declines in proportion to the rise in education and personal income"1. This correlation isn't new and was also observed in ancient Greece by Polybius (200-118BCE)2.

The effect extends beyond individual countries and is visible inter-nationally. Countries with a higher rate of belief in God have lower average intelligence. All countries with high average intelligence have low national levels of belief in God. For countries where belief in God is over 80%, the average national IQ is 83 points. For those countries where stated disbelief in God (atheism) is greater than 20%, the national average IQ is 98 points. Instead of belief in God, countries with the highest IQs adhere to Far-Eastern belief systems such as Buddhism, Taoism and Shintoism. It is not just intelligence and education that is inversely correlated with religion - it has also been found that the more you know about religion itself, the less likely you are to be religious3.

1. Religion and Science

1.1. Bias When Searching for Truth

#christianity #greece

If you think you have the answers, you are less likely to search for the truth. If you are an engineer in ancient Greece who thinks that the microscope has proven that neurones work through hydraulic pressure, you are not likely to question this truth without very convincing evidence: your search has largely ended. Your background belief (as an engineer in this example) has primed you, and biased you towards accepting the hydraulic neurone theory. Those who believe that "God works in mysterious ways" and believe in miracles, magic and prayer, and that God makes the planets orbit the sun, are less likely to have enquiring minds about how such things work.

Scientists had to suffer torture, silencing, imprisonment and death at the hands of Christians who didn't agree with newly discovered facts about the world. Christianity lost the first battle with astronomers who realized that, contrary to what Christians asserted, the Sun did not orbit the Earth, and that the Universe doesn't seem to be designed specifically for humankind. Copernicus (1473-1543), Kepler (1571-1630), Galileo (1564-1642), Newton (1643-1727) and Laplace (1749-1827) all fought battles against the Church when they published scientific papers challenging religious orthodoxy. Bible verses were all the theories Christians needed; and Joshua 10:12-13, 2 Kings 20:11, Psalms 93:1, 104:5, Ecclesiastes 1:5, Isaiah 30:26, Isaiah 38:8, 1 Thessalonians 4:16-18 and Habakkuk 3:10-11 all contradicted astronomers. But through intelligence and clever politics, truth gradually won out over dogma, and the Church retreated... only to go on to fight similar ignorant battles, and violently impose dogmatic errors, in the arenas of physics, biology and philosophy.

Without such interference from theists, science would have been more than a thousand years more advanced! Kepler in the 17th century only revived Greek astronomical knowledge that was condemned and hidden by Christians (Ptolemy et al) in the second century.

"Christianity v. Astronomy: The Earth Orbits the Sun!: 8. Conclusions" by Vexen Crabtree (2006)

American scientists are less religious than the American public generally [and] the most distinguished scientists are the least religious of all

"The God Delusion" by Prof. Richard Dawkins (2006)4

Not only did their religion prevent them from thinking in the correct terms about basic physics, biology and astronomy, and not only did their atheist counterparts continue to search for truth while they did not, but their beliefs gave them a false confidence to actively punish those that disagreed. The whole series of battles between religion and science (which science has always won) shows us empirically and historically that religion suppresses science.

The stubborn stance against science and real-world knowledge in Christianity stems from the very founders of that religion. Take Tertullian, one of the great and powerful Christian speakers of very early Christianity, who in 200CE was defending Christianity against its critics. 'Before he closes his defense, Tertullian renews an assertion which, carried into practice, as it subsequently was, affected the intellectual development of all Europe. He declares that the Holy Scriptures are a treasure from which all the true wisdom in the world has been drawn; that every philosopher and every poet is indebted to them. He labors to show that they are the standard and measure of all truth, and that whatever is inconsistent with them must necessarily be false'5. And what a terrible legacy became of that mode of thought: it is only true if it says so in the Bible. The hallmark of ignorant, dangerous barbarianism and fundamentalism.

Thankfully for the study of truth, the process of secularisation has diminished the strength of religion across the West, and since the Enlightenment, when religious institutions started to lose control of public life, education continues to act as an anti-religion force in the world: the more educated a person is, the less likely they are to be religious. Education is the key to leading successful, happy and above all, a meaningful life devoid of nonsense. The future looks bright for many. Although Europe excels (in a patchy way) in all-faiths education where religions cannot stamp their particular dogmas over science education, this is not the case in much of the rest of the world, so there is much work yet to do in combatting anti-science religiosity.

1.2. Non-Religious People Can Become Better Scientists


Richard Dawkins (2006) summarizes on the religious beliefs of Nobel-Prize winners, the members of the top scientific organisations in the USA and the UK, and finds that only a small percent believe in a personal God, even in countries where god-belief is extensive. Because those who do not subscribe easily to dogmatic lines of thought are naturally more inquisitive, they are the ones more likely to discover new facts about the world. This is perhaps why most scientists are atheists. A large survey confirmed that becoming a scientist does not lead to a loss of religious conviction6; but, those who are free from it are simply more likely to want to study the world objectively, and therefore to become good scientists. The less religious they are, the better they become at science.

Book CoverThe only website I could find that claimed to list 'Nobel Prize-winning Christians' came up with six, out of a total of several hundred scientific Nobelists. Of these six, it turned out that four were not Nobel Prize-winners at all; and at least one, to my certain knowledge, is a non-believer who attends church for purely social reasons. A more systematic study by Benjamin Beit-Hallahmi 'found that among Nobel Prize laureates in the sciences, as well as those in literature, there was a remarkable degree of irreligiosity, as compared to the populations they came from.'52

A study in the leading journal Nature by Larson and Witham in 1998 showed that of those American scientists considered eminent enough by their peers to have been elected to the National Academy of Sciences (equivalent to being a fellow of the Royal Society in Britain) only about 7 per cent believe in a personal God53. This overwhelming preponderance of atheists is almost the exact opposite of the profile of the American population at large, of whom more than 90 per cent are believers in some sort of super-natural being. [...] It is completely as I would expect that American scientists are less religious than the American public generally, and that the most distinguished scientists are the least religious of all. [...]

The overwhelming majority of [fellows of the Royal Society], like the overwhelming majority of US Academicians, are atheists. Only 3.3 per cent of the Fellows agreed strongly with the statement that a personal god exists [...] while 78.8 per cent strongly disagreed [...]. There were a massive 213 unbelievers and a mere 12 believers.

"The God Delusion" by Prof. Richard Dawkins (2006)7
References 52 and 53 are duplicated at the bottom of this page.

Studies have found that a general "connectedness with god" is associated with lower levels of education8. Prof. Kyung reports the findings of many studies into religion and intelligence, and the chart on the right is my reproduction of the first chart on one of his pages, taken from data in a Scientific American article (1999)9. Many of these studies are probably mentioned below by Dawkins. 39 studies since 1927 have found that the more educated a person is, and the higher one's intelligence, the less likely someone is to hold religious beliefs. It shows that those with a degree in science are less than half as likely to believe in God as the general populace, and eminent scientists are nine times less likely.

This correlation isn't new. A historian of ancient Greece, Polybius (200-118BCE) says that in his time, educated and enlightened men knew as "a matter of course that all this talk about the gods and the underworld is a myth which nobody among the better classes takes seriously" and that in political circles there was an active attempt to curb belief in gods2.

2. Religion and General Intelligence

2.1. The More Religious the Parents, the Less Intelligent the Children (Persisting Into Adulthood)

There is a reason why god-believing adults rarely become scientists, and almost never become top scientists. Not only does theology and dogmatic religious assertions interfere with correct scientific thought, but, children of religious parents have on average, lower intelligence. This common-sense finding is not a one-off statistic, but part of an entire trend. The stricter the religious beliefs of the parent, the less the average intelligence of the child.

Sociologist Zena Blau of the University of Houston recently conducted a study of more than a thousand children in Chicago. [...] In 1981 Blau reported that IQs were lowest among children whose mothers have overly strict religious beliefs. Children whose mothers were from a non-denominational or non-religious background had the highest average IQs - 110 for whites, 109 for blacks. Children whose mothers belonged to "fundamentalist" religious groups tended to have IQs that were 7 to 10 points lower. According to Blau, these religion-IQ differences hold even when you take into account the mother's social class, current occupational status, and education.

"Understanding Human Behavior" by James V. McConnel (1986)10

This has a resultant effect on educational attainment:

A 2005 Gallup International study called "Voice of the People" surveyed fifty thousand people in more than sixty-five countries and found that people with secondary or high-level education are less religious than people with no education or only a basic education.

"50 Reasons People Give for Believing in a God" by Guy Harrison (2008)11

Several research studies have been published on the statistical relationship between religiosity and educational level, or religiosity and IQ. Michael Shermer, in How We Believe: The Search for God in an Age of Science, describes a large survey of randomly chosen Americans that he and his colleague Frank Sulloway carried out. [...] Religiosity is indeed negatively correlated with education (more highly educated people are less likely to be religious). Religiosity is also negatively correlated with interest in science. [...]

[Paul Bell in Mensa Magazine, 2002, reviewed all studies taken of religion and IQ. He concluded:]

"Of 43 studies carried out since 1927 on the relationship between religious belief and one's intelligence and/or educational level, all but four found an inverse connection. That is, the higher one's intelligence or education level, the less one is likely to be religious or hold "beliefs" of any kind."

"The God Delusion" by Prof. Richard Dawkins (2006)12

It is easy to see how a cycle may emerge: If some people are prompted to adopt some religious beliefs, their children will have less IQ. They will therefore be more likely to take up religious beliefs more strictly. If they do so, their children will have even less average intelligence, and perhaps adopt even stricter religious behaviours. A cycle. This cycle would be most readily shaken by education imposed from without, on a national scale. Public education is a good defence against communities cycling into la-la land. Also, sometimes such as during the enlightenment, a general changing in culture can break the hold of specific forms of religious inhibition, and break the cycle. In the West, a gradual counter-cycle of individualism ended the dark ages and allowed the West's cultural ascent.

2.2. Religious Countries Have a Lower Average IQ

#atheism #christianity

All the studies so far have concentrated on individual measurements of IQ, and how they correlate with religiosity. In the West, this largely correlates with Christian religiosity. Because most of these studies are performed in the West, it is possible that secularism and atheism is correlated with higher intelligence simply because Christianity has a particularly negative effect on intelligence. To explore this further, we need to see if these trends exist in various cultures, where the background religion is not Christianity.

Scattergraph of national average IQ and national belief in god

Source: Lynn, Harvey & Nyborg (2009)13

A study of data for belief in God and intelligence across 137 countries was undertaken by Lynn, Harvey & Nyborg (2009)13, with the latest comprehensive sets of data available, which were mostly from 2004. The data shows conclusively that countries with a higher average IQ have less belief in God - they state that "in only 17% of the countries (23 out of 137) does the proportion of the population who disbelieve in God rise above 20%. These are virtually all the higher IQ countries".

For countries where belief in God is over 80%, the average national IQ is 83.0 points. For those countries where stated disbelief in God is greater than 20%, the national average IQ is 98.0 points.

Many of the highest-IQ countries are historically, and currently, associated with Buddhism, Shintoism and Taosim. Nearly half of the population of Singapore, which has the highest-recorded average national IQ, follow either Buddhism or Taoism. The next highest countries, Japan and S. Korea, have similar cultures to Singapore, although nowadays 50% of those in Japan do not state that they any religion at all.

Some of the least theistic countries are communist, or ex-communist, states where religion has been actively suppressed by government, and in these countries low belief in God does not exist alongside high national IQ, but, aside from those, most countries with low rates of belief in God have the best range of national average IQ.

2.3. The Exceptions of Minority Religions14

#buddhism #UK #wicca

Book CoverThere are exceptions to the general rule that religion is linked with lower intelligence. Some esoteric or obscure religions attract particularly educated fans. Sometimes this results from an anti-establishment source amongst students or adults, sometimes it is because a particular style of religion gains a very positive image. Buddhism in the UK once attained this status and a wide range of intellectuals flocked to newly formed Buddhist societies and the like. These were later criticized for misrepresenting Buddhism, in particular by omitting irrational and societal elements of it. A survey in 1998 found that nearly 75% of the followers of the Friends of the Western Buddhist Order (one of the largest UK Buddhist groups) had a first degree, compared to 11% of the rest of the population. A third of them also had higher degrees.15.

Wiccans tend to be much better educated than average. A UK survey by Pearson (2000) found "half of the Wiccans were university educated, seven had a masters degree, nine had doctorates, and one was studying for a doctorate. [...] Only one person was seeking employment"16. Needless to say, other authors have noted the same. The historian Ronald Hutton states that Wiccans display "a higher than usual love of reading and commitment to constant self-education" (1999)17 and J.B. Russell also notes that "most witches are relatively well educated" (1991)18.

Some minority religions attract a disproportionately intelligent following because they are hard to engage with, therefore, those that attach themselves to the religion are the types of people who commit strongly to their interests in life. In all cases, as such movements gain in numbers and diversify to include more types of followers, this initial trend diminishes.

3. The Benefits and Side-Effects of Questioning Beliefs19

Philosophy is questions that may never be answered. Religion is answers that may never be questioned.

-- Anon.

There is a constant need for us to question our own beliefs, and the beliefs of those around us. It creates a healthy atmosphere of skepticism and intelligence, and prevents people from coming to unreasonable conclusions. The way our brains work mean that we frequently misinterpret events and data, and in particular, we always think there is more rationality and evidence for our beliefs than there is. This all matters because when beliefs become unquestioned, a community can become increasingly divorced from reality. This is especially true when individual leaders or belief-based authorities claim to be acting in accord with a divine principle, such as God's will. When it comes to disputes, religionists can come to deny any chance of compromise. In the adult world of democratic politics, compromise in disputes is what keeps things from breaking down: you give a little in one area, but have to give up in another. However arguments based on differences in religion or belief often contain parties that believe the issue has universal, absolute and cosmic significance. They will not compromise on their position, and many ordinary believers state that they think that religious beliefs should be somehow beyond question20. Malise Ruthven in his book on fundamentalism warns that this is particularly dangerous21. It is how religious cults are formed. In extreme cases this leads to complete social rejection and the possibility of suicide cults, as has been seen many times in history for example with Charles Manson's followers and the 900 who died when the People's Temple suicided. These groups always start out with borderline, but common, beliefs and slowly become more delusional over time. In all cases followers lacked an instinct to ask questions about the beliefs. It is religion that gains most when people cease asking deep questions about beliefs, and it is truth that suffers most. Thomas Paine famously remarked that "it is error only, and not truth, that shrinks from inquiry"22. In the name of truth and common sense, do not let even trivial-seeming beliefs take hold without double-checking them, because once beliefs are trivialised, a slippery slope can take you down into madness!

"Why Question Beliefs? Dangers of Placing Ideas Beyond Doubt, and Advantages of Freethought: 4. Conclusion" by Vexen Crabtree (2009)

4. Religious People Know Least About Religion23

#agnosticism #atheism #christianity #education #religious_studies #USA

Following on from the idea that questioning ideas is the hallmark of good education, good intelligence, and an anti-religious attitude, it has been found that the non-religious are some of the most educated about religion. A Pew Forum poll in 2010 found that educational level is the biggest predictor of knowledge of basics facts about Christianity and world religion in the USA, but in addition, that those who know most are also atheists and agnostics3. In other words - the more you know about religion, the less likely you are to be religious.

Current edition: 2007 Jan 01
Last Modified: 2017 Jan 11
Parent page: Human Religions

Social Media

References: (What's this?)

Book Cover

Book Cover

Book Cover

Book Cover

Book Cover

Book Cover

Skeptical Inquirer. Magazine. Published by Committee for Skeptical Inquiry, NY, USA. Pro-science magazine published bimonthly.

The Bible (NIV). The NIV is the best translation for accuracy whilst maintaining readability. Multiple authors, a compendium of multiple previously published books. I prefer to take quotes from the NIV but where I quote the Bible en masse I must quote from the KJV because it is not copyrighted, whilst the NIV is. Book Review.

Beckerlegge, Gwilym
(2001, Ed.) From Sacred Text to Internet. Paperback book. Published by Ashgate Publishing Ltd, Aldershot, UK, in association with The Open University, Milton Keynes, UK. This was a course book for the OU module "Religion Today: Traditional, Modernity and Change" which ran until 2011.

Crabtree, Vexen
(2006) "Christianity v. Astronomy: The Earth Orbits the Sun!" (2006). Accessed 2017 Mar 10.
(2014) "What is Science and the Scientific Method?" (2014). Accessed 2017 Mar 10.

Dawkins, Prof. Richard
(2006) The God Delusion. Hardback book. Published by Bantam Press, Transworld Publishers, Uxbridge Road, London, UK.

52: Beit-Hallahmi, Benjamin & Argyle, M. (1997). The Psychology of Religious Behaviour, Belief and Experience. London: Routledge.
53: E. J. Larson and L. Witham, 'Leading scientists still reject God', Nature 394, 1998, 313.

Drachmann, Anders Björn. (1860-1935) Professor of Classical Philology in the University of Copenhagen.
(1922) Atheism in Pagan Antiquity. E-book. Gutenberg Project ebook. Originally published 1919 in Danish, Kjoebenhavns Universitets Festskrift. Translated by Ingeborg Andersen.

Draper, John William. (1811-1882)
(1881) History of the Conflict Between Religion and Science. E-book. 8th (Amazon Kindle digital edition) edition. Published by D. Appleston and Co, New York, USA.

Eliade, Mircea
(1987, Ed.) The Encyclopedia of Religion. Hardback book. Published by Macmillan Publishing Company, New York, USA. 16 huge volumes. Eliade is editor-in-chief. Entries are alphabetical, so, no page numbers are given in references, just article titles.

Harrison, Guy P.
(2008) 50 Reasons People Give for Believing in a God. E-book. Amazon Kindle digital edition. Published by Prometheus Books, New York, USA.

Hutton, Ronald
(1999) The Triumph of the Moon: A History of Modern Pagan Witchcraft. Paperback book. 2001 edition. Published by Oxford University Press, Oxford, UK.

IHEU. International Humanist and Ethical Union.
(2012) Freedom of Thought. A copy can be found on of Thought 2012.pdf, accessed 2013 Oct 28.

McConnel, James V.
(1986) Understanding Human Behavior. Hardback book. 5th edition. Originally published 1974. Current version published by CBS College Publishing, Holt Rinehart and Winston, New York, USA.

NSS. The National Secular Society, London, UK.
Newsline. Weekly news letter. See: "Secularism" by Vexen Crabtree (2011).

Pearson, Joanne
(2002, Ed.) Belief Beyond Boundaries: Wicca, Celtic Spirituality and the New Age. Paperback book. Published by Ashgate Publishing Ltd, Aldershot, UK, in association with The Open University, Milton Keynes, UK.

Russell, J.B.
(1991) A History of Witchcraft: Sorcerers, Heretics and Pagans. First published 1980. Published by Thames & Hudson, London, UK. In "Belief Beyond Boundaries: Wicca, Celtic Spirituality and the New Age" by Joanne Pearson (2002).

Ruthven, Malise
(2007) Fundamentalism. Originally published 2005. Current version published by Oxford University Press, Oxford, UK. New edition now published as part of the “Very Short Introduction” series.


  1. IHEU (2012) p9. Added to this page on 2015 Jan 10.^
  2. Drachmann (1922) chapter 5. Added to this page on 2017 Jan 11.^^
  3. Pew Forum on Religion and Public Life research results "U.S. Religious Knowledge Survey" (2010 Sep 28). From a poll conducted in May and June 2010 involving 3412 American adults.^^
  4. Dawkins (2006) p101.^
  5. Draper (1881) p45.^
  6. National Secular Society, Newsline (2007 Jul 06) . Added to this page on 2007 Nov 03.^
  7. Dawkins (2006) p100-103.^
  8. Schieman et al. (2006). Journal for the Scientific Study of Religion (2006) 45(4):529-549. Scott Schieman is professor of sociology at the University of Toronto, USA.^
  9. Scientific American 1999 Sep, article "Scientists and Religion in America", reported on Prof. Kyung's website at, accessed 2007 Jan 01. Eliade Mircea (1987) in the entry in Volume 8 on Leuba, James (1868-1946), says he is an "American psychologist and one of the leading figures of the early phase of the American psychology of religion movement. [...] Leuba was responsible for the classic study on religious beliefs among scientists and psychologists. He found that the more eminent the scientist, the less likely he was to profess religious beilefs. The same finding held for psychologists".^
  10. McConnel (1986) p555-6.^
  11. Harrison (2008) chapter 45 "Atheism is a negative and empty philosophy" digital location 3231. Added to this page on 2017 Jan 10.^
  12. Dawkins (2006) p102-103.^
  13. Richard Lynn, John Harvey and Helmuth Nyborg article "Average intelligence predicts atheism rates across 137 nations" in Intelligence (2009 Jan/Feb) vol. 37 issue 1 pages 11-15. Online at, accessed 2009 Sep 15. The graph is produced from the data by Vexen Crabtree. Added to this page 2009 Sep 13.^
  14. Added to this page on 2011 Jun 08.^
  15. Helen Waterhouse "Representing western Buddhism: a United Kingdom focus", chapter 3 in "From Sacred Text to Internet" by Gwilym Beckerlegge (2001) p149.^
  16. Pearson (2002) Chapter 4, p145.^
  17. Hutton (1999) p402.^
  18. Russell (1991) p171.^
  19. Added to this page on 2012 Aug 17.^
  20. Harrison (2008) chapter 1: "My god is obvious".^
  21. Ruthven (2007) Chapter 6 "Fundamentalism and Nationalism II" p98-103.^
  22. Skeptical Inquirer (2012 Sep/Oct) p10. The quote comprises part of an advert for the Center for Inquiry, a skeptical think-tank.^
  23. Added to this page on 2014 Mar 12.^
  24. 2013 Apr 12: I have re-made the chart in Religious Countries Have a Lower Average IQ and slightly updated the text, adding comments on the highest-IQ countries.

© 2017 Vexen Crabtree. All rights reserved.