Religion is a set of beliefs which people use to guide them through life. They may involve beliefs about life’s origins, about how one should live one’s life, and about what happens after death.
Beliefs are not proofs, though holders of such beliefs may imagine them to be so. They may begin as assumptions, evolve into rules for living, and embody wishful thinking and deeply held desires.
In those senses, religions are attempts to solve the problems of living. They provide a story, a rationale, a guide and a reassurance. A very human need, and a comfort in adversity.
Intelligence is negatively correlated with religious belief. Correlation is often misunderstood, because most correlations are less than unity (-0.7 between intelligence and religious belief). Real world correlations usually indicate a tendency, not a certainty. They hint at a cause, but do not prove it. Correlation is not a disproof of a causal link, and is often the first identification of a causal link, but it is merely the first step, not a proof. Correlation is not always causation, but may be a first step to identifying a cause.
The negative correlation often provokes believers, by way of disproof, to give an example of a well-known, very clever person who is also religious. Bertrand Russell was right when he made his weary observation “popular induction depends upon the emotional interest of the instances, not upon their number” (The Validity of Inference, Chp 23, Basic Writings, 1961).
Cribari-Neto and Souza have published a recent overview “Religious belief and intelligence: Worldwide evidence”
They know that intelligence positively correlates with atheism, but go on to show that intelligence impacts atheism even when they account for economic development. Religious beliefs lose strength, on average, as a country becomes richer. In most African countries the percentage of nonbelievers does not exceed 1% (Zuckerman, 2007) whereas in Sweden it reaches 64%. Kanazawa (2009) found that “each point in national IQ decreases the proportion of the population who believes in God by more than a percentage point”. Lewis, Ritchie, and Bates (2011) have shown that lower intelligence is most strongly associated with higher levels of religious fundamentalism. They also show openness negatively correlates with religious fundamentalism.Cribari-Neto and Souza then go on to construct impact curves of intelligence on religious disbelief. This argument using beta regression models is quite complex, but to put it in plain language, once an average national IQ of 105 is achieved (global IQ is about 93) there is a strong impact on religious belief. Further increases in national IQ lead to significant drops in belief, but less strongly so. A coarse view would be that by IQ 105 the population “see through” religious explanations, and if they continue to hold on to them, it is not because of intellectual limitations.
Despite these findings, some people argue that the correlation may be influenced by cultural effects taking place at the family level, namely that some households are religious and others are not, and that somehow this explains away or reduces any conclusions which can be drawn on the basis of the correlation.
So, it is with particular interest that one turns to the issue of religious belief within families. All siblings are subjected to the same parental beliefs as part of their upbringing. Will there be difference between siblings in terms of religious belief as a consequence of differences in their intelligence?
Yoav Ganzach and Chemi Gotlibovski “Intelligence and religiosity: Within families and over time” http://www.sciencedirect.com.libproxy.ucl.ac.uk/science/article/pii/S0160289613000962
They studied the 1997 cohort of the National Longitudinal Survey of Youth (NLSY97). The NLSY97 is a probability sample of 8984 Americans (with over sampling of Afro-Americans, Hispanics and economically disadvantaged whites) born between 1980 and 1984. About 35% were Catholic, 26% Baptists, 29% other Protestants, and the rest from small denominations and religions. The participants came from 6819 households, 1862 of them included more than one participant. As a result 3192 of the participants came from households that included two participants and 835 came from households that included 3 or more participants (as 96% of the same household participants were siblings, they use the term “siblings” rather than the “same household members”). They find that differences in religiosity between siblings are determined by intelligence.
They say: “The current results provide strong empirical evidence for a causal link between intelligence and religiosity. The cross-sectional analysis suggests that intelligence influenced cross-sectional differences in religiosity, and that this effect cannot be explained by background correlates of intelligence. The longitudinal analysis, which focused on changes on religiosity (and therefore did not examine the effect of intelligence on levels of religiosity) suggests that intelligence drove changes in religiosity in that the more intelligent were primarily those that became less religious.”
“Our analysis also provided some insight into the process by which intelligence affected changes in religiosity over time. It suggests that when growing up, the more intelligent became less religious because of two, perhaps even three, reasons. First, they obtained more education, which in turn negatively affected their religiosity. Second, controlling for changes in education, they were more influenced by the processes of growing up than the less intelligent. And third, education tended to have a stronger effect on their religiosity than on the religiosity of the less intelligent, although the evidence for this effect is weak.”
In summary, the relationship between intelligence and the absence of religious belief looks pretty strong.
Bertrand Russell thought it “odd that modern men, who are aware of what science has done in the way of bringing new knowledge and altering the conditions of social life, should still be willing to accept the authority of texts embodying the outlook of very ancient and very ignorant pastoral or agricultural tribes.”
Of course, we should not consider it odd, merely that it is part of human frailty to pray for good things and hope for the best, including even the life everlasting. Fingers crossed may be silly, but according to Pascal’s Wager a little silliness does no harm if it is low cost, and might conceivably prevent a great harm.
May all your gods and your comforts go with you.