Relation between intelligence and religion…

1. Introduction
2. Intelligence and Religious Belief within Nations
2.1 Negative Correlation between Intelligence and Religious Belfief
2.2 Lesser Religious Inclination in the Intellectual Elite
2.3 Decline of Religious Belief with Age
2.4 Decline of the Relgious Belief in the 20th century
3. Mean I.Q of Atheists, Agnostics and Believers
4. Intelligence and Religious Belief accross Nations

5. Discussion
6. Mean I.Q by Religion

Annex: Nations, Nation I.Q and atheists frequence


There is an inverse correlation between intelligence and religious inclination, at both an individual and a national level.

Study conducted by Lynn Richard (1), John Harvey (2) and Helmuth Nyborg (3).

(1) University of Ulster, Coleraine, Northern Ireland (2) Drove Cottages, Rodmell, Lewes, East Sussex, England and (3) University of Aarhus, Denmark.


It is shown that intelligence measured in psychometric g (general intelligence) is negatively related to religious belief. We also examine whether this negative relationship between intelligence and religious belief is present among nations. We find that, in a sample of 137 countries, the correlation between I.Q and atheism is 0.60. At the individual level, the correlation between I.Q and religious inclination is -0.88.

1. Introduction     

Dawkins’ recent book “The god delusion” suggests that it is not smart to believe in the existence of God. In this paper we will examine (1) the proof of this assertion, that is, whether there is a negative relation between intelligence and religious belief; (2) whether the negative relationship between intelligence and religious belief is a difference in psychometric terms; and (3) whether there is a negative relationship between intelligence and religious belief among nations.

2. Intelligence and Religious Belief within Nations

We are far from being the first to suggest the existence of a negative relationship between intelligence and religious belief within nations. This phenomenon was observed in the 1920s by Howells (1928) and Sinclair (1928), both of whom reported studies showing negative correlations between intelligence and religious beliefs among students of -. 27 and -. 29 to -. 36 (using different measures of religious belief). In the 1950s Argyle (1958) concluded that “smart students are much less likely to accept orthodox beliefs, and a little less likely to have pro-religious attitudes”.
Evidence of a negative relationship between intelligence and religious belief within nations comes from four sources: These are (1) negative correlations between intelligence and religious belief, (2) a smaller proportion of religious beliefs among intellectual elites relative to the general population; (3) a decline in religious belief with age in children and adolescents, their cognitive abilities increasing; (4) a decline in religious belief during the twentieth century, as the intelligence of the population has increased.

2.1 Negative Correlation between Intelligence and Religious Belief

A number of studies have found negative correlations between intelligence and religious belief. A review was conducted by Bell (2002): 43 studies, all but four of which found a negative correlation. Added to this is a study in the Netherlands of a nationally representative sample (total N = 1538) which indicated that agnostics have 4 more I.Q points than believers (Verhage, 1964). In a more recent study Kanazawa (2007) analyzed data from the American National Longitudinal Study of Adolescent Health, a national sample first tested for intelligence with PPVT (Peabody Picture Vocabulary Test) (N = 14277) . During this interview, they were asked: “How religious are you?” Responses were coded as “non-religious”, “not religious”, “moderately religious” and “very religious”. The results showed that the “non-religious” obtained the highest I.Q (103.09), followed in descending order by the other three groups (I.Q = 99.34, 98.28, 97.14). The relationship between I.Q and religious belief is very significant (F (3, 14273) = 78.0381, p <.00001).

2.2  There is a lower percentage of believers in intellectual elites than in the general population

In the corroboration of these studies, intelligence and religious belief were found to be negatively correlated by comparing the percentage of believers among the elites in relation to the general population. This was shown in 1921 in a survey of the religious beliefs of eminent scientists and American researchers found that 39% said they believed in God (with a range from 48% for historians to 24% among psychologists ) (Leuba, 1921). It was reported by Roe (1965) that among a group of 64 prominent scientists, 61 were indifferent to religion, “which leaves about 4.8% believers. This is much lower than the percentage of believers in the population of which 95.5% in the United States declared that they believed in God in 1948 Gallup Poll (Argyle, 1958). In the 1990s, a study of members of the American National Academy of Sciences reported that 7% believed in the existence of God, compared to about 90% in a poll of the general population (Larsen and Witham 1998). In Britain, it was reported that 3.3% of fellows of the Royal Society believed in the existence of God, while 78.8% do not believe (the rest were undecided) (Dawkins, 2006). At the same time, a survey revealed that 68.5% of the total population believes in the existence of God.

2.3  Decline in Religious Belief with Age in Children and Adolescents

Decline in religious belief during adolescence and adulthood as cognitive ability increases. This was found in the United States for the age group of 12-18 by Kuhlen and Arnold (1944) who reported that among 12-year-olds 94% agree with the statement “I believe there is a God “, while among 18 years it had dropped to 78%. Similarly, in England, Francis (1989) found a decline in religious belief in the 5-16 age group. The religious belief was measured by a scale including questions such as “God means a lot to me” and “I think people who pray are stupid”, etc., and scores on the scale are shown in abbreviated form in the Table 1. The fact that girls get higher scores (they believe more) that boys were often found (see, for example, Argyle, 1958) In another study, 12-15 years in a Protestant school in Northern Ireland, we find that attitudes favorable to religion continue to fall significantly (p <.001), each year by about 0.75 standard deviation over 4 years, while the correlations between a pro-religionist attitude and IQ become increasingly negative and significant (p <.001) (Turner, 1980) These results are summarized in Table 2. (These trends are less clear for a Catholic Roman school).

Table 1. Decline in percentage holding religious belief, with age (Francis,1989)

Age N Boys Girls
5-6 400 87.9 96.0
11-12 400 79.6 84.1
15-16 400 55.7 70.4

Table 2. Declining belief Correlates with Age (sd =15.6)(Turner,1980)

Age N Belief


R: Non-belief x IQ
12 50   69.54   0.183
13 50   66.10   0.110
14 50   59.86  -0.113
15 50   57.94  -0.354*

* significant at p<.01

2.4  Decline of Religious Belief in the Twentieth Century, as the Intelligence of the Population Has Increased

There is evidence of a decline in religious belief over the last 150 years or at the same time the intelligence of the population has increased. The increase in intelligence is a well-documented phenomenon that has become known as the Flynn effect. The decline of religious belief has been demonstrated by attendance statistics of the church and belief in God recorded in opinion polls. For example, in England, church attendance declined from 40% of the population in 1850 to 35% in 1900, to 20% in 1950, to 10% in 1990 (Giddens, 1997, p.460). Attendance at The Church of England Easter week declined from 9% of the population in 1900 to 5% in 1970 (Argyle and Beit-Hallahmi, 1975), participation of children on Sunday declined from 30% of the child population in 1900 to 13% in 1960 (Goldman, 1965). Gallup polls show that 72% of the population in 1950 claimed to believe in God (Argyle, 1958), but by 2004 it had dropped to 58.5% (Zuckerman, 2006).
There has also been some decline in religious belief in the last century in the United States. Hoge (1974) examined several studies that found a decline in religious belief in college students. For example, Bryn Mawr students were asked if they believed in a God who answered prayer. Positive responses were given by 42% of students in 1894, 31% in 1933, and 19% in 1968. Students who enroll at the University of Michigan were asked to mention whether or not they were believers. In 1896, 86% of students claimed to believe in God. In 1930 70%, and in 1968 44%. At Harvard, Radcliffe, Williams, and Los Angeles City College, the percentages of student believers in God, praying daily or fairly often, and attending church about once a week, all declined from 1946 to 1966. Heath ( 1969) also reported a decline in belief in God among students from 79% in 1948 to 58% in 1968. Among the general population, Gallup polls revealed that 95.5% believed in God in 1948 (Argyle, 1958 ), compared to 89.5% in 2004 (Zuckerman, 2006).

3. Mean I.Q of Atheists, Agnostics and Believers

Religion intelligence

To determine whether there is a negative relationship between religious belief and Psychometric g (the general intelligence factor), data from the National Longitudinal Survey of Youth (NLSY97) were analyzed. NLSY97, a national sample, is selected to represent approximately 15 million American adolescents in the 12-17 age group in 1997. Subjects (N = 6825) were asked about their religious inclination and also tested by the Armed Services Vocational Aptitude Battery (CAT-ASVAB97). This test consists of twelve scales. These were analyzed in terms of Raschian probabilistic modeling and the dimensions of a correlation scale .992 (Psychometric R) with general information, g, (main axis factor analysis (t (N-2) = 662 , 62, p <.000).

Atheists earned 6 more Q.I points than all subjects in the group professing either of a large number of different religions. The difference in intelligence between atheists and believers was important even without the help of weighted data (t (1, 6.893) = 2.87, p = .004).

4. Intelligence and Religious Belief accross Nations

pays religion intelligence

To study the relationship between intelligence and religious belief among nations, we took the nation I.Qs in Vanhanen and Lynn (2006) IQ and global inequality. This source indicates that these national IQs have a high level of reliability, as shown by the correlation of ,92 of the different measures, and validity, as shown by the correlation of ,83 of IQ and the level of education. The high reliability and validity of these national I.Qs has been confirmed by Rindermann (2007). We took the figures of Zuckerman’s (2007) belief in God, which gives data for 137 countries, representing just over 95% of the world’s population. These data were collected primarily from surveys conducted in 2004, although in a few countries, surveys were a year or two earlier. These data were collected from a number of surveys to provide results as up-to-date as possible. There is more than one survey for a given country. Zuckerman draws attention to four issues related to this dataset: low response rates, weaknesses in random sample selection, diet or peer pressure that influence responses, and problems with terminological variation between cultures on terms such as “religious” or “secular”. Despite these possible sources of error however Zuckerman quotes Robert Putnam “we must do with the imperfection of evidence that we can find, not just lamenting its shortcomings.”
The data for I.Q and the percentages claiming to believe in God for the 137 countries are given in the appendix. Only 17% of countries (23 out of 137) find that the proportion of people who do not believe in God is above 20%. These are virtually all of I.Q’s highest countries.

Correlations between the national I.Q and atheism are given in Table 3. Line 1 gives a correlation of 0.60 for the total sample and is statistically significant (p <.001). We also divided the countries into two groups those with an average I.Q between 64-86 and those of I.Q average between 87-108. Line 2 presents the data for the 69 countries with I.Q between 64-86. In this group, only 1.95% of the population is non-believers. Line 3 gives the data for 68 countries with I.Q between 87-108. In this group 16.99% of the population are non-believers

Table 3. Correlations between the National IQs and Religious Disbelief

IQs N.Countries Non-Believers Range Non-Believers R: Non-belief x IQ
64-108  137  10.69%  <1% to 81%  +0.60
64-86   69   1.95%  <1% to 40%  +0.16
87-108   68  16.99%  <1% to 81%  +0.54

5. Discussion

The results raise four points of interest.

First, the hypothesis with which we began this study is that there is a negative correlation between I.Q and religious belief. Second, we have shown that the negative relationship between intelligence and religious belief is a difference in Psychometric g. Third, we have extended this assumption to the question of whether a negative correlation between I.Q and religious belief is present between countries. Using data from 137 countries, we found a correlation of 0.60 between I.Q and unbelief in God. The measure used for analysis between the countries was unbelief in God rather than believing in God. We believe that one can reasonably assume that god’s disbelief is very (negatively) correlated with belief in god. Therefore, we conclude that the negative correlation between I.Q and the religious belief that has been found in many studies within nations is also present between nations.

Second, this conclusion raises the question of why there is a negative correlation between I.Q and belief in god. Many rationalists will no doubt accept the argument advanced by Frazer (1922, p.712) in The Golden Bough that in developed civilizations “the quick-witted states the theory of religious nature insufficient … religion, considered an explanation of nature, is replaced by science “. Others have implicitly or explicitly assumed that more intelligent people are more likely to question religious dogmas. For example, Kuhlen and Arnold (1944) suggest that “greater intellectual maturity may increase religious skepticism.” Inglehart and Welzel (2005, p.27) suggest that in the preindustrial world, humans have little control over nature, so they seek to compensate for their lack of physical control by appealing to the powers of metaphysics that seem to control the world: worship is seen as a means of influencing its fate, and it is easier to to accept his helplessness if one knows that the result is in the hands of an all-powerful being, whose benevolence can not be won by following rigid and predictable rules of contact … a reason for the decline of beliefs Traditional nuns in industrial societies is that the growing sense of technology allows control over nature and diminishes the need to rely on supernatural powers. ”

Third, there are some exceptions to the general rule of linear relationship between I.Q and unbelief in God across nations. Two of the most abnormal are Cuba and Vietnam, which have higher percentages of unbelievers in God (40% and 81%, respectively) than their Q.Is of 85 and 96 (respectively) would predict. This is probably due to communism and strong atheist propaganda against religious belief. In addition, it has sometimes been suggested that communism is itself a form of religion in which Das Capital is the sacred text, Lenin was the Messiah who came to bring paradise to earth, while Stalin, Mao, Castro, and others were his disciples, who came to spread the message in different countries.

Fourth, the United States has a very low percentage of unbelievers in God (10.5%) for a high average I.Q. The percentage of disbelievers in God in the United States is much lower than in northwestern and central Europe (for example, Belgium, 43%, Netherlands, 42%, Denmark, 48% France, 44%, United Kingdom, 41.5%). One factor that might provide a possible explanation for this is that many Americans are Catholic, and the percentage of believers in Catholic countries in Europe is generally much higher than in Protestant countries (eg Italy, 6% of atheists, Ireland, 5%, Poland, 3%, Portugal 4%, Spain 15%). Another possible contribution is the immigration of those with strong religious beliefs. Another possible factor might be that a number of emigrants from Europe went to the United States because of their strong religious beliefs, so these beliefs were passed on as a cultural entity and even as genetic inheritance to succeeding generations. The Parent-Child correlation of religious beliefs is quite high: 0.64 (father-son) and 0.69 (mother-daughters) (Newcomb and Svehla, 1937). It has been found that religious belief has a heritability of about 0.40 – 0.50 (Koenig, McGrue, Krueger and Bouchard, 2005), it is possible that a number of religious emigrants from Europe had the genetics of religious belief, which has been transmitted to most of the current population

6. Mean I.Q by Religion

The table below shows the various American religious movements and their classification (atheist, agnostic, liberal and dogmatic).

Jews (Ashkenazim in America) have the highest proportion of individuals with high IQ, 33% of American Jews have an average IQ greater than 120. They are followed by Anglicans, atheists and agnostics with 29, 25 and 19% respectively of individuals with an IQ greater than 120.

Dogmatic religions attract lower IQs. Muslims have the lowest proportion of gifted individuals (4%) followed in ascending order by Baptists (8%), Pentecostists (9%) and Mormons (11%) . The racial factor is obviously to be taken into account. Ashkenazi Jews have an higher I.Q genetically while Middle Easterners and North Africans, on the other hand, have a lower intelligence and constitute the majority of Muslims. Baptists and Pentecotists have a large proportion of African-Americans.

high intelligence religion

Among White (European) Americans, atheists have an average I.Q slightly higher than agnostics, followed by liberal religious and then by dogmatic religious who have the lowest intelligence (Table 5).

I.Q atheism religion

Religion obviously has no direct impact on intelligence, which is a physiological parameter of the brain essentially determined by genes. It is a previously lower average IQ that will attract some to a more dogmatic religion (pre-rational, with magical thoughts, fixed rules of behavior, emphasis on sins, need for atonement …), while the more high IQs will prefer rational explanations and atheism (even more liberal religions for reflection and interpretation, whose followers have an intermediate IQ).

H. Nyborg (2009) The intelligence–religiosity nexus: a representative study of white adolescent americans H. Nyborg Intelligence 37, 81–93.

Nations, National I.Q and Atheists Frequency

Country IQ % Not believing in God
Afghanistan 84 0.5
Albania 90 8
Algeria 83 0.5
Angola 68 1.5
Argentina 93 4
Armenia 94 14
Australia 98 25
Austria 100 18
Azerbaijan 87 0.5
Bangladesh 82 0.5
Belarus 97 17
Belgium 99 43
Benin 70 0.5
Bolivia 87 1
Botswana 70 0.5
Brazil 87 1
Brunei 91 0.5
Bulgaria 93 34
Burkina Faso 68 0.5
Burundi 69 0.5
Cambodia 91 7
Cameroon 64 0.5
Canada 99 22
Central African Rep. 64 1.5
Chad 68 0.5
Chile 90 2
China 105 12
Colombia 84 1
Congo: Rep of (Brazz) 64 2.7
Costa Rica 89 1
Cote d’Ivoire 69 0.5
Croatia 90 7
Cuba 85 40
Czech Republic 98 61
Denmark 98 48
Dominican Republic 82 7
Ecuador 88 1
Egypt 81 0.5
El Salvador 80 1
Estonia 99 49
Ethiopia 64 0.5
Finland 99 28
France 98 44
Gambia 66 0.5
Georgia 94 4
Germany 99 42
Ghana 71 0.5
Greece 92 16
Guatemala 79 1
Guinea 67 0.5
Haiti 67 0.5
Honduras 81 1
Hungary 98 32
Iceland 101 16
India 82 3
Indonesia 87 1.5
Iran 84 4.5
Iraq 87 0.5
Ireland 92 5
Israel 95 15
Italy 102 6
Jamaica 71 3
Japan 105 65
Jordan 84 0.5
Kazakhstan 94 12
Kenya 72 0.5
Kuwait 86 0.5
Kyrgyzstan 90 7
Laos 89 5
Latvia 98 20
Lebanon 82 3
Liberia 67 0.5
Libya 83 0.5
Lithuania 91 13
Madagascar 82 0.5
Malawi 69 0.5
Malaysia 92 0.5
Mali 69 0.5
Mauritania 76 0.5
Mexico 88 4.5
Moldova 96 6
Mongolia 101 20
Morocco 84 0.5
Mozambique 64 5
Namibia 70 4
Nepal 78 0.5
Netherlands 100 42
New Zealand 99 22
Nicaragua 81 1
Niger 69 0.5
Nigeria 69 0.5
Norway 100 31
Oman 83 0.5
Pakistan 84 0.5
Panama 84 1
Paraguay 84 1
Peru 85 1
Philippines 86 0.5
Poland 99 3
Portugal 95 4
Romania 94 4
Russia 97 27
Rwanda 70 0.5
Saudi Arabia 84 0.5
Senegal 66 0.5
Sierra Leone 64 0.5
Singapore 108 13
Slovakia 96 17
Slovenia 96 35
Somalia 68 0.5
South Africa 72 1
South Korea 106 30
Spain 98 15
Sri Lanka 79 0.5
Sweden 99 64
Switzerland 101 17
Syria 83 0.5
Taiwan 105 24
Tajikistan 87 2
Tanzania 72 0.5
Thailand 91 0.5
Togo 70 0.5
Trinidad & Tobago 85 9
Tunisia 83 0.5
Turkmenistan 87 2
Uganda 73 0.5
Ukraine 97 20
United Arab Emirates 84 0.5
United Kingdom 100 41.5
United States 98 10.5
Uruguay 96 12
Uzbekistan 87 4
Venezuela 84 1
Vietnam 94 81
Yemen 85 0.5
Zambia 71 0.5
Zimbabwe 66 4


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