Religiosity and intelligence
The debate on religiosity and intelligence explores the link between religiosity and issues related to intelligence and educational level (by country and on the individual level). Religiosity and intelligence are both complex topics that include diverse variables, and the interactions among variables are not always well understood. For instance, intelligence is often defined differently by different researchers  and also all scores from intelligence tests are only estimates of intelligence because concrete measurements, like those of mass or distance, cannot be achieved given the abstract nature of the concept of "intelligence". In terms of religiosity, it involves wide variations of interactions of religious beliefs, practices, behaviors, and affiliations in diverse cultures.
A meta-analysis found a negative correlation between intelligence quotient (IQ) and religiosity for western societies. The correlation was suggested to be a result of nonconformity, more cognitive and less intuitive thinking styles among the less religious, and less of a need for religion as a coping mechanism. Some studies have shown a correlation between national average IQ and levels of atheism in society, although others have questioned whether any correlations are due to a complex range of social, economic and historical factors, which interact with religion and IQ in different ways. Others argue that any differences in national IQ and levels of atheism are not necessarily due to levels of religiosity or nonreligiosity, but are correlated with economic, educational, environmental, and social factors. Less developed and poorer countries tend to be more religious, perhaps because religions play a more active social, moral and cultural role in those countries.
In terms of thinking styles, one study suggests that intuitive thinking may be one out of many sources that affect levels of religiosity and that analytical thinking may be one out of many sources that affect disbelief. However, others who have reviewed studies on analytic thinking and nonbelievers, suggest that analytical thinking does not imply better reflection on religious matters or disbelief.
A global study found that some Western religious traditions and the nonreligious correlate with high levels of education. On the individual level, one study observed that education level is positively correlated with a belief in a god in African countries, and negatively correlated in Western countries. The frequency of church visits is however positively correlated with education level in English-speaking countries as well as in Protestant Europe.
- 1 Definitions and issues
- 2 Studies comparing religious belief and IQ
- 3 Factors that influence IQ
- 4 See also
- 5 References
- 6 Further reading
Definitions and issues
The definitions of intelligence are controversial since at least 70 definitions have been found among diverse fields of research. Some groups of psychologists have suggested the following definitions:
A very general mental capability that, among other things, involves the ability to reason, plan, solve problems, think abstractly, comprehend complex ideas, learn quickly and learn from experience. It is not merely book learning, a narrow academic skill, or test-taking smarts. Rather, it reflects a broader and deeper capability for comprehending our surroundings—"catching on," "making sense" of things, or "figuring out" what to do.
Individuals differ from one another in their ability to understand complex ideas, to adapt effectively to the environment, to learn from experience, to engage in various forms of reasoning, to overcome obstacles by taking thought. Although these individual differences can be substantial, they are never entirely consistent: a given person's intellectual performance will vary on different occasions, in different domains, as judged by different criteria. Concepts of "intelligence" are attempts to clarify and organize this complex set of phenomena. Although considerable clarity has been achieved in some areas, no such conceptualization has yet answered all the important questions, and none commands universal assent. Indeed, when two dozen prominent theorists were recently asked to define intelligence, they gave two dozen, somewhat different, definitions.
Intelligence is a property of the mind that encompasses many related abilities, such as the capacities to reason, to plan, to solve problems, to think abstractly, to comprehend ideas, to use language, and to learn. There are several ways to more specifically define intelligence. In some cases, intelligence may include traits such as creativity, personality, character, knowledge, or wisdom. However, some psychologists prefer not to include these traits in the definition of intelligence.
A widely researched index or classification of intelligence among scientists is intelligence quotient (IQ). IQ is a summary index, calculated by testing individuals' abilities in a variety of tasks and producing a composite score to represent overall ability, e.g., Wechsler Adult Intelligence Scale. It is used to predict educational outcomes and other variables of interest.
Others have attempted to measure intelligence indirectly by looking at individuals' or group's educational attainment, although this risks bias from other demographic factors, such as age, income, gender and cultural background, all of which can affect educational attainment.
Dissatisfaction with traditional IQ tests has led to the development of alternative theories. In 1983, Howard Gardner proposed the theory of multiple intelligences, which broadens the conventional definition of intelligence, to include logical, linguistic, spatial, musical, kinesthetic, naturalist, intrapersonal and interpersonal intelligences. He chose not to include spiritual intelligence amongst his "intelligences" due to the challenge of codifying quantifiable scientific criteria, but suggested an "existential intelligence" as viable.
The term religiosity refers to degrees of religious behaviour, belief, or spirituality. The measurement of religiosity is hampered by the difficulties involved in defining what is meant by the term. Numerous studies have explored the different components of religiosity, with most finding some distinction between religious beliefs/ doctrine, religious practice, and spirituality. Studies can measure religious practice by counting attendance at religious services, religious beliefs/ doctrine by asking a few doctrinal questions, while spirituality can be measured by asking respondents about their sense of oneness with the divine or through detailed standardized measurements. When religiosity is measured, it is important to specify which aspects of religiosity are referred to.
According to Mark Chaves, decades of anthropological, sociological, and psychological research have established that "religious congruence" (the assumption that religious beliefs and values are tightly integrated in an individual's mind or that religious practices and behaviors follow directly from religious beliefs or that religious beliefs are chronologically linear and stable across different contexts) is actually rare. People’s religious ideas, are fragmented, loosely connected, and context dependent; like in all other domains of culture and in life. The beliefs, affiliations, and behaviors of any individual are complex activities that have many sources including culture. As examples of religious incongruence he notes, "Observant Jews may not believe what they say in their Sabbath prayers. Christian ministers may not believe in God. And people who regularly dance for rain don’t do it in the dry season." 
Demographic studies often show wide diversity of religious beliefs, belonging, and practices in both religious and non-religious populations. For instance, out of Americans who are not religious and not seeking religion: 68% believe in God, 12% are atheists, 17% are agnostics; in terms of self-identification of religiosity 18% consider themselves religious, 37% consider themselves as spiritual but not religious, and 42% consider themselves as neither spiritual nor religious; and 21% pray every day and 24% pray once a month. Global studies on religion also show diversity.
Studies comparing religious belief and IQ
In a 2013 meta-analysis of 63 studies, led by Professor Miron Zuckerman, a correlation of -.20 to -.25 between religiosity and IQ of was particularly strong when assessing beliefs (which in their view reflects intrinsic religiosity) but the negative effects were less when comparing with behavior (such as church going). They note limitations on this since viewing intrinsic religiosity as being about religious beliefs represents American Protestantism more than Judaism or Catholicism, both of which see behavior as just as important as religious beliefs. They also noted that the available data did not allow adequate consideration of the role of religion type and of culture in assessing the relationship between religion and intelligence. Most of the studies reviewed were American and 87% participants in those studies were from the United States, Canada, and the United Kingdom. They noted "Clearly, the present results are limited to Western societies." The meta-analysis discussed three possible explanations: First, intelligent people are less likely to conform and, thus, are more likely to resist religious dogma, however this theory was contradicted in mostly atheist societies such as the Scandinavian populations, where the religiosity-IQ relationship still existed. Second, intelligent people tend to adopt an analytic (as opposed to intuitive) thinking style, which has been shown to undermine religious beliefs. Third, Intelligent people may have less need for religious beliefs and practices, as some of the functions of religiosity can be given by intelligence instead. Such functions include the presentation of a sense that the world is orderly and predictable, a sense of personal control and self-regulation and a sense of enhancing self-esteem and belongingness.
Researcher Helmuth Nyborg and Richard Lynn, emeritus professor of psychology at the University of Ulster, compared belief in God and IQs. Using data from a U.S. study of 6,825 adolescents, the authors found that the average IQ of atheists was 6 points higher than the average IQ of non-atheists. The authors also investigated the link between belief in a god and average national IQs 137 countries. (For the purposes of this article, it should be noted that 'belief in a god' does not correlate with 'religiosity'. Some nations have high proportions of people who do not believe in a god, but who may nevertheless be highly religious, following non-theistic belief systems such as Buddhism or Taoism.) The authors reported a correlation of 0.60 between atheism rates and level of intelligence, which was determined to be "highly statistically significant".
The Lynn et al. paper findings were discussed by Professor Gordon Lynch, from London's Birkbeck College, who expressed concern that the study failed to take into account a complex range of social, economic and historical factors, each of which has been shown to interact with religion and IQ in different ways. Gallup surveys, for example, have found that the world's poorest countries are consistently the most religious, perhaps because religion plays a more functional role (helping people cope) in poorer nations. Even at the scale of the individual, IQ may not directly cause more disbelief in gods. Dr. David Hardman of London Metropolitan University says: "It is very difficult to conduct true experiments that would explicate a causal relationship between IQ and religious belief." He adds that other studies do nevertheless correlate IQ with being willing or able to question beliefs.
Other correlations between national IQs and other factors are available, Richard Lynn and Vanhanen claimed that national IQs are correlated with per capita income at a correlation of .73. However, when long GDP (1975 – 2003) were used, the correlations increased to .82 for 81 nations. Further study confirmed the results for 185 countries (r =.65) and for 152 countries (r =.76).
According to biopsychologist Nigel Barber, the differences in national IQ between and levels of religiosity or atheism are better explained by social, environmental, and wealth conditions than by levels of religiosity. He acknowledges that highly intelligent people have been both religious and nonreligious. He notes that countries with more wealth and better resources tend to have higher levels of non-theists and countries that have less wealth and resources tend to have less non-theists. For instance, countries that have poverty, low urbanization, lower levels of education, less exposure to electronic media that increase intelligence, experience diseases that impair brain function, low birth weights, child malnutrition, poor control of pollutants like lead, have more issues that reduce brain and IQ development than do wealthier or more developed countries.
Researcher Gregory S. Paul suggests that economic development has a closer relationship with religiosity. He argues that once any "nation's population becomes prosperous and secure, for example through economic security and universal health care, much of the population loses interest in seeking the aid and protection of supernatural entities." Other studies have shown that increased wealth is correlated with a decline in religious beliefs. Indeed, the majority of the nations that showed a strong relationship between low religiosity and high IQ in the 2008 study were developed nations.
Studies examining theistic and atheistic cognitive style
The idea that analytical thinking makes one less likely to be religious is an idea held by some studies on this issue, including a report from Harvard University. First of all, the Harvard researchers found evidence suggesting that all religious beliefs become more confident when participants are thinking intuitively (atheists and theists each become more convinced). Thus reflective thinking generally tends to create more qualified, doubted belief.
Furthermore, the Harvard study found that participants who tended to think more reflectively were less likely to believe in a god. Reflective thinking was further correlated with greater changes in beliefs since childhood: these changes were towards atheism for the most reflective participants, and towards greater belief in a god for the most intuitive thinkers. The study controlled for personality differences and cognitive ability, suggesting the differences were due to thinking styles – not simply IQ or raw cognitive ability. An experiment in the study found that participants moved towards greater belief in a god, after writing essays about how intuition yielded a right answer or reflection yielded a wrong answer (and conversely, towards atheism if primed to think about either a failure of intuition or success of reflection). The authors say it is all evidence that a relevant factor in religious belief is thinking style. The authors add that, even if intuitive thinking tends to increase belief in a god, "it does not follow that reliance on intuition is always irrational or unjustified."
A study by Gervais and Norenzayan reached similar conclusions that intuitive thinking tended to increase belief in intrinsic religiosity, intuitive religious belief and belief in supernatural entities. They also added a causative element, finding that subtly triggering analytic thinking can increase religious disbelief. They concluded that "Combined, these studies indicate that analytic processing is one factor (presumably among several) that promotes religious disbelief." While these studies linked religious disbelief to analytical rather than intuitive thinking, they urged caution in the interpretation of these results, noting that they were not judging the relative merits of analytic and intuitive thinking in promoting optimal decision making, or the merits or validity of religiosity as a whole.
Reviewing psychological studies on atheists, Miguel Farias, noted that studies concluding that analytical thinking leads to lower religious belief "do not imply that that atheists are more conscious or reflective of their own beliefs, or that atheism is the outcome of a conscious refutation of previously held religious beliefs" since they too have variant beliefs such as in conspiracy theories of the naturalistic variety. He notes that studies on deconversion indicate that a greater proportion of people who leave religion, do so for motivational rather than rational reasons and the majority of deconversions occur in adolescence and young adulthood when one is emotionally volatile. Furthermore, he notes that atheists are indistinguishable from New Age individuals or Gnostics since there are commonalities such as being individualistic, non-conformist, liberal, and valuing hedonism and sensation.
Concerning the cognitive science studies on atheists, Johnathan Lanman notes that there are implicit and explicit beliefs which vary among individuals. An individual's atheism and theism may be related to the amount of "credibility enhancing displays" (CRED) one experiences in that those who are exposed more to theistic CRED will likely be theist and those who have less exposure to theistic CRED will likely be atheists.
Neurological research on mechanisms of belief and non-belief, using Christians and atheists as subjects, by Harris et al. have shown that the brain processes beliefs and facts the same way no matter what the content is. In other words, there is no difference, from the view point of the brain, between a theistic belief/unbelief, atheistic belief/unbelief, or any other mundane belief/unbelief even when believers and nonbelievers accepted and rejected diametrically opposite statements. The same neural networks were active in both Christians and Atheists even when dealing with "blasphemous statements" to each other's worldviews. Furthermore, it supports the reality that "intuition" and "reason" are not two separate and segregated activities but are intertwined in both theists and atheists when they come to any personal conclusions or convictions.
Studies examining religiosity and emotional intelligence
A small 2004 study by Ellen Paek examined the extent to which religiosity (in which only Christians were surveyed), operationalized as religious orientation and religious behaviour, is related to the controversial idea of emotional intelligence (EI). The study examined the extent to which religious orientation and behavior were related to self-reported (EI) in 148 church attending adult Christians. (non-religious individuals were not part of the study). The study found that the individuals' self-reported religious orientation was positively correlated with their perceiving themselves to have greater EI. While the number of religious group activities was positively associated with perceived EI, number of years of church attendance was unrelated. Significant positive correlations were also found between level of religious commitment and perceived EI. Thus, the Christian volunteers were more likely to consider themselves emotionally intelligent if they spent more time in group activities and had more commitment to their beliefs.
Tischler, Biberman and McKeage warn that there is still ambiguity in the above concepts. In their 2002 article, entitled "Linking emotional intelligence, spirituality and workplace performance: Definitions, models and ideas for research", they reviewed literature on both EI and various aspect of spirituality. They found that both EI and spirituality appear to lead to similar attitudes, behaviors and skills, and that there often seems to be confusion, intersection and linking between the two constructs.
Recently, Łowicki and Zajenkowski investigated the potential associations between various aspects of religious belief and ability and trait EI. In their first study they found that ability EI was positively correlated with general level of belief in God/Higher Power. Next study conducted among Polish Christians replicated the previous result, as well as revealed that both trait and ability EI were negatively related to extrinsic religious orientation and negative religious coping.
Studies exploring religiosity and educational attainment
The relationship between the level of religiosity and one's level of education has been a philosophical, as well as a scientific and political concern since the second half of the 20th century.
The parameters in this field are slightly different compared to those brought forward above: if the "level of religiosity" remains a concept which is difficult to determine scientifically, on the contrary, the "level of education" is, indeed, easy to compile, official data on this topic being publicly accessible to anyone in most countries.
Different studies available show contrasting conclusions. An analysis of World Values Survey data showed that in most countries, there is no significant relationship between education and religious attendance, with some differences between "western" countries and former socialist countries, which they attribute to historical/ political/ economic factors (not intelligence). Other studies have noted a positive relationship.
A 2016 Pew Center global study on religion and education around the world ranked Jews as the most educated (13.4 years of schooling) followed by Christians (9.3 years of schooling). The religiously unaffiliated—a category which includes atheists, agnostics and those who describe their religion as “nothing in particular”—ranked overall as the third most educated religious group (8.8 years of schooling) followed by Buddhists (7.9 years of schooling), Muslims (5.6 years of schooling), and Hindus (5.6 years of schooling). In the youngest age (25-34) group surveyed, and Jews averaged 13.8 years of schooling, the unaffiliated group averaged 10.3 years of schooling, Christians averaged 9.9 years of schooling, Buddhists averaged 9.7 years of schooling, Hindus averaged 7.1 years of schooling, and Muslims averaged 6.7 years of schooling. 61% of Jews, 20% of Christians, 16% of the unaffiliated, 12% of Buddhists, 10% of Hindus, and 8% of Muslims have graduate and post-graduate degrees. The study observed that the probability of having a college degree in the U.S. is higher for all religious minorities surveyed (due to selective immigration policies that favor highly skilled applicants), including the unaffiliated group which ranks in the fifth place, being higher than the national average of 39%.
According to a 2016 Pew Center study, there is correlation between education and income in the United States. About 77% of Hindus have a graduate and post-graduate degree, 67% to less than the national average (depending on the size of denominational groups) of Christians, 59% of Jews, 47% of Buddhists, 43% of Atheists, 42% of Agnostics, 39% of Muslims, and 24% of those who say their religion is “nothing in particular”; have a graduate and post-graduate degree.
Factors that influence IQ
Micronutrients and vitamin deficiencies
Micronutrient deficiencies (e.g. in iodine and iron) influence the development of intelligence and remain a problem in the developing world. For example, iodine deficiency causes a fall, on average, of 12 IQ points.
Heritability is defined as the proportion of variance in a trait which is attributable to genotype within a defined population in a specific environment. A number of points must be considered when interpreting heritability. The general figure for the heritability of IQ, according to an authoritative American Psychological Association report, is 0.45 for children, and rises to around 0.75 for late adolescents and adults. It may seem reasonable to expect genetic influences on traits like IQ to become less important as one gains experiences with age. However, the opposite occurs. Heritability measures in infancy are as low as 0.2, around 0.4 in middle childhood, and as high as 0.8 in adulthood. One proposed explanation is that people with different genes tend to reinforce the effects of those genes, for example by seeking out different environments.
Family members have aspects of environments in common (for example, characteristics of the home). This shared family environment accounts for 0.25–0.35 of the variation in IQ in childhood. By late adolescence, it is quite low (zero in some studies). The effect for several other psychological traits is similar. These studies have not looked at the effects of extreme environments, such as in abusive families.
David Rowe reported an interaction of genetic effects with socioeconomic status, such that the heritability was high in high-SES families, but much lower in low-SES families. In the US, this has been replicated in infants, children, adolescents, and adults. Outside the US, studies show no link between heritability and SES. Some effects may even reverse sign outside the US.
Dickens and Flynn (2001) have argued that genes for high IQ initiate an environment-shaping feedback cycle, with genetic effects causing bright children to seek out more stimulating environments that then further increase their IQ. In Dickens' model, environment effects are modeled as decaying over time. In this model, the Flynn effect can be explained by an increase in environmental stimulation independent of it being sought out by individuals. The authors suggest that programs aiming to increase IQ would be most likely to produce long-term IQ gains if they enduringly raised children's drive to seek out cognitively demanding experiences.
- Neisser, Ulrich; Boodoo, Gwyneth; Bouchard, Thomas J.; Boykin, A. Wade; Brody, Nathan; Ceci, Stephen J.; Halpern, Diane F.; Loehlin, John C.; Perloff, Robert; Sternberg, Robert J.; Urbina, Susana (1996). "Intelligence: Knowns and unknowns" (PDF). American Psychologist. 51: 77–101. doi:10.1037/0003-066x.51.2.77. ISSN 0003-066X. Retrieved 9 October 2014.
- Haier, Richard. The Neuroscience of Intelligence. Cambridge University Press. pp. 18–19. ISBN 9781107461437.
- Holdcroft, Barbara (September 2006). "What is Religiosity?". Catholic Education: A Journal of Inquiry and Practice. 10 (1): 89–103.
- Zuckerman, Miron; Silberman, Jordan; Hall, Judith A. (2013). "The Relation Between Intelligence and Religiosity: A Meta-Analysis and Some Proposed Explanations". Personality and Social Psychology Review. 17: 325–354. doi:10.1177/1088868313497266.
- Lynn, Richard; John Harvey; Helmuth Nyborg (2009). "Average intelligence predicts atheism rates across 137 nations". Intelligence. 37: 11–15. doi:10.1016/j.intell.2008.03.004. Retrieved 2015-05-25.
- Graeme, Paton (11 June 2008). "Intelligent people 'less likely to believe in God'". The Telegraph.
- Barber, Nigel (May 4, 2010). "The Real Reason Atheists Have Higher IQs: Is Atheism a Sign of Intelligence?". Psychology Today.
- Crabtree, Steve; Pelham, Brett (6 March 2009). "Religion Provides Emotional Boost to World's Poor". Gallup Poll.
- Gervais, W. M.; Norenzayan, A. (26 April 2012). "Analytic Thinking Promotes Religious Disbelief" (PDF). Science. 336 (6080): 493–496. doi:10.1126/science.1215647. PMID 22539725. Retrieved 24 January 2016.
- Farias, Miguel (2013). "30. Psychology of Atheism". In Bullivant, Stephen; Ruse, Michael. The Oxford Handbook of Atheism. Oxford: Oxford Univ. Press. ISBN 0199644659.
- "Religion and Education Around the World" (PDF). Pew Research Center. December 19, 2011. Retrieved December 13, 2016.
- S. Legg; M. Hutter. "A Collection of Definitions of Intelligence". 157: 17–24.
- Gottfredson 1997777, pp. 17–20
- Gottfredson, Linda S. (1997). "Mainstream Science on Intelligence (editorial)" (PDF). Intelligence. 24: 13–23. doi:10.1016/s0160-2896(97)90011-8. ISSN 0160-2896.
- Gardner, Howard. Multiple Intelligences. ISBN 0-465-04768-8.
- Gardner, Howard (January 2000). "A Case Against Spiritual Intelligence". The International Journal for the Psychology of Religion. 10 (1): 27–34. doi:10.1207/S15327582IJPR1001_3.
- Gardner, Howard (1999). Intelligence reframed: multiple intelligences for the 21st century. Basic Books. p. 53.
- Chaves, Mark (March 2010). "SSSR Presidential Address Rain Dances in the Dry Season: Overcoming the Religious Congruence Fallacy". Journal for the Scientific Study of Religion. 49 (1): 1–14. doi:10.1111/j.1468-5906.2009.01489.x.
- "American Nones: The Profile of the No Religion Population" (PDF). American Religious Identification Survey. 2008. Retrieved 2014-01-30.
- "Religion and the Unaffiliated". "Nones" on the Rise. Pew Research Center: Religion & Public Life. October 9, 2012.
- "Most of the Religiously Unaffiliated Still Keep Belief in God". Pew Research Center. November 15, 2012.
- "The Global Religious Landscape". Pew Research Center.
- Meisenberg, G. (2004). "Talent, character and the dimensions of national culture". Mankind Quarterly. 45: 123–169.
- Whetzel, Deborah L.; McDaniel, Michael A. (September 2006). "Prediction of national wealth". Intelligence. 34 (5): 449–458. doi:10.1016/j.intell.2006.02.003.
- MORSE, STEPHEN (September 2008). "The geography of tyranny and despair: development indicators and the hypothesis of genetic inevitability of national inequality". Geographical Journal. 174 (3): 195–206. doi:10.1111/j.1475-4959.2008.00296.x.
- Paul, G.S. (2009). "The Chronic Dependence of Popular Religiosity upon Dysfunctional Psychosociological Conditions" (PDF). Evolutionary Psychology. 7 (3): 398–441.
- "Religion & Wealth: Less Religious Countries are More Wealthy". Atheism.about.com. Retrieved 2013-03-05.
- Survey Reports. "World Publics Welcome Global Trade — But Not Immigration | Pew Global Attitudes Project". Pew Research Center. Retrieved 2013-03-05.
- "Analytic thinking can decrease religious belief, study shows". Science Daily. 26 April 2012.
- Shenhav, Amitai; Rand, David G.; Greene, Joshua D. (2011). "Divine Intuition: Cognitive Style Influences Belief in God, by Amitai Shenhav, David G. Rand, and Joshua D. Greene at Harvard University" (PDF).
- Lanman, Johnatahn (2013). "31. Atheism and Cognitive Science". In Bullivant, Stephen; Ruse, Michael. The Oxford Handbook of Atheism. Oxford: Oxford Univ. Press. ISBN 0199644659.
- Harris, Sam; Kaplan, Jonas T.; Curiel, Ashley; Bookheimer, Susan Y.; Iacoboni, Marco; Cohen, Mark S.; Sporns, Olaf (1 October 2009). "The Neural Correlates of Religious and Nonreligious Belief". PLoS ONE. 4 (10): e7272. doi:10.1371/journal.pone.0007272. PMC . PMID 19794914.
- Miller, Lisa (September 30, 2009). "THE BRAIN PROCESSES FACTS AND BELIEFS THE SAME WAY". Newsweek.
- Eysenck, H.J. (2000). Intelligence: A New Look. ISBN 0-7658-0707-6.
- Locke, E.A. (2005). "Why emotional intelligence is an invalid concept". Journal of Organizational Behavior. 26 (4): 425–431. doi:10.1002/job.318.
- Mattiuzzi, Paul G. "Emotional Intelligence? I'm not feeling it.". EverydayPsychology.com.
- Paek, Ellen (2006). "Religiosity and perceived emotional intelligence among Christians". Personality and Individual Differences. International Society for the Study of Individual Differences. 41 (3): 479–490. doi:10.1016/j.paid.2006.01.016. ISSN 0191-8869.
- Tischler, L; Biberman, J.; McKeage, R. (2002). "Linking emotional intelligence, spirituality and workplace performance: Definitions, models and ideas for research". Journal of Managerial Psychology. Emerald Group Publishing Limited. 17 (3): 203–218. doi:10.1108/02683940210423114. ISSN 0268-3946. Retrieved 2008-10-18.
- Łowicki, Paweł; Zajenkowski, Marcin. "Divine Emotions: On the Link Between Emotional Intelligence and Religious Belief". Journal of Religion and Health. doi:10.1007/s10943-016-0335-3.
- Sacerdote, Bruce; Glaeser, Edward L. "Education and Religion" (PDF). Harvard Institute of Economic Research. p. 29. Retrieved 6 January 2012.
- Norris, Pippa; Ronald Inglehart (2011). Sacred and Secular: Religion and Politics Worldwide (2nd ed.). Cambridge University Press. pp. 267–268. ISBN 978-1-107-64837-1.
The effects of income become insignificant, however, the impact of education actually reverses in the United States: it is the more educated who attend church most frequently. It therefore appears that the typical socioeconomic profile of churchgoing is indeed somewhat distinctive in the United States when compared with other wealthy countries.
- "Education and occupation profile of attenders". NCLS Research. 2004.
- "The most and least educated U.S. religious group". Pew Research Center. 2016-10-16.
- Tucker-Drob, Elliot M; Briley, Daniel A (2014), "Continuity of Genetic and Environmental Influences on Cognition across the Life Span: A Meta-Analysis of Longitudinal Twin and Adoption Studies", Psychological Bulletin, 140 (4): 949–979, doi:10.1037/a0035893, PMC , PMID 24611582
- Qian M, Wang D, Watkins WE, et al. (2005). "The effects of iodine on intelligence in children: a meta-analysis of studies conducted in China". Asia Pacific Journal of Clinical Nutrition. 14 (1): 32–42. PMID 15734706.
- International Journal of Epidemiology, Volume 35, Issue 3, June 2006. See reprint of Leowontin's 1974 article "The analysis of variance and the analysis of causes" and 2006 commentaries: http://ije.oxfordjournals.org/content/35/3.toc
- Aguiar, Sebastian (31 October 2014). "Intelligence: The History of Psychometrics". http://ieet.org. Instititute for Ethics and Emerging Technologies. Retrieved 9 November 2015. External link in
- Neisser, Ulric; Boodoo, Gwyneth; Bouchard, Thomas J. Jr.; Boykin, A. Wade; Brody, Nathan; Ceci, Stephen J.; Halpern, Diane F.; Loehlin, John C.; et al. (1996). "Intelligence: Knowns and unknowns". American Psychologist. 51 (2): 77–101. doi:10.1037/0003-066X.51.2.77.
- Bouchard, Thomas J. (2013). "The Wilson Effect: The Increase in Heritability of IQ With Age". Twin Research and Human Genetics. 16 (05): 923–930. doi:10.1017/thg.2013.54. ISSN 1832-4274. PMID 23919982.
- Panizzon, Matthew S.; Vuoksimaa, Eero; Spoon, Kelly M.; Jacobson, Kristen C.; Lyons, Michael J.; Franz, Carol E.; Xian, Hong; Vasilopoulos, Terrie; Kremen, William S. (2014). "Genetic and environmental influences on general cognitive ability: Is g a valid latent construct?". Intelligence. 43: 65–76. doi:10.1016/j.intell.2014.01.008. ISSN 0160-2896.
- Neisser, Ulrich; Boodoo, Gwyneth; Bouchard, Thomas J.; Boykin, A. Wade; Brody, Nathan; Ceci, Stephen J.; Halpern, Diane F.; Loehlin, John C.; Perloff, Robert; Sternberg, Robert J.; Urbina, Susana (1996). "Intelligence: Knowns and unknowns" (PDF). American Psychologist. 51: 77–101. doi:10.1037/0003-066x.51.2.77. ISSN 0003-066X. Retrieved 9 October 2014.
- Bouchard Jr, TJ (1998). "Genetic and environmental influences on adult intelligence and special mental abilities.". Human biology; an international record of research. 70 (2): 257–79. PMID 9549239.
- Plomin, R; Asbury, K; Dunn, J (2001). "Why are children in the same family so different? Nonshared environment a decade later.". Canadian Journal of Psychiatry. 46 (3): 225–33. PMID 11320676.
- (Harris 2009)
- Rowe, D. C.; Jacobson, K. C. (1999). "Genetic and environmental influences on vocabulary IQ: parental education level as moderator". Child Development. 70 (5): 1151–62. doi:10.1111/1467-8624.00084.
- Tucker-Drob, E. M.; Rhemtulla, M.; Harden, K. P.; Turkheimer, E.; Fask, D. (2011). "Emergence of a Gene x Socioeconomic Status Interaction on Infant Mental Ability Between 10 Months and 2 Years". Psychological Science. 22: 125–33. doi:10.1177/0956797610392926. PMC . PMID 21169524.
- Turkheimer, E.; Haley, A.; Waldron, M.; D'Onofrio, B.; Gottesman, I. I. (2003). "Socioeconomic status modifies heritability of IQ in young children". Psychological Science. 14 (6): 623–628. doi:10.1046/j.0956-7976.2003.psci_1475.x. PMID 14629696.
- Harden, K. P.; Turkheimer, E.; Loehlin, J. C. (2005). "Genotype environment interaction in adolescents' cognitive ability". Behavior Genetics. 35: 804–804.
- Bates, Timothy C.; Lewis, Gary J.; Weiss, Alexander (2013-10-01). "Childhood Socioeconomic Status Amplifies Genetic Effects on Adult Intelligence". Psychological Science. 24 (10): 2111–2116. doi:10.1177/0956797613488394. ISSN 0956-7976. PMID 24002887.
- Tucker-Drob, Elliot M.; Bates, Timothy C. (2015-12-15). "Large Cross-National Differences in Gene × Socioeconomic Status Interaction on Intelligence". Psychological Science: 0956797615612727. doi:10.1177/0956797615612727. ISSN 0956-7976. PMID 26671911.
- Hanscombe, K. B.; Trzaskowski, M.; Haworth, C. M.; Davis, O. S.; Dale, P. S.; Plomin, R. (2012). "Socioeconomic Status (SES) and Children's Intelligence (IQ): In a UK-Representative Sample SES Moderates the Environmental, Not Genetic, Effect on IQ.". PLoS ONE. 7 (2): e30320. doi:10.1371/journal.pone.0030320. PMC . PMID 22312423.
- Dickens, William T.; Flynn, James R. (2001). "Heritability estimates versus large environmental effects: The IQ paradox resolved.". Psychological Review. 108 (2): 346–69. doi:10.1037/0033-295X.108.2.346. PMID 11381833.
- Dickens, William T.; Flynn, James R. (2002). "The IQ Paradox: Still Resolved" (PDF). Psychological Review. 109 (4): 764–771. doi:10.1037/0033-295x.109.4.764.