This is the fifth and final installment of my series on what we know (and don’t know) about intelligence and religion. These were inspired by questions about and challenges to a video I was in, particularly questions about my statement that the religious are not more or less intelligent than the non-religious. In part one, I introduced the series by briefly discussing some of the very diverse areas of one’s life that are impacted by your religious belief system. Part two focused on the relationship between religion and educational attainment. The religious beliefs of scientists were examined in part three, while part four focused on what we know, based on research studies, about level of intelligence and religiosity. The purpose of this last piece is to put a TL;DR on the series by giving a summary of the total literature I have reviewed and a road map for where researchers need to go next in order to more definitively provide an an answer to the question “Who’s more intelligent, theists or non-theists?”
In part two, early studies analyzing religious belief and educational attainment showed that greater church attendance often correlates with obtaining a slightly higher level of education, although later studies found the opposite. When religious devotees are identified as fundamentalist or liberal, however, amount of church attendance becomes less significant and level of fundamentalism becomes the major determinant of educational attainment. Commitment to religious fundamentalism and attainment of higher education appear to be almost mutually exclusive. Fundamentalists are less likely to enroll in college preparatory classes than are their liberal counterparts, and they typically terminate their educational pursuits at a lower level. In addition, religious beliefs tend to become slightly more liberal during college. The literature appears to support the idea that people who hold fundamentalist religious beliefs are at an educational disadvantage.
Results from the studies reviewed in part three suggest that scientists are more likely to hold agnostic, atheistic, or liberal religious beliefs than they are to hold fundamentalist or orthodox beliefs. Scientists also appear to be significantly less religious than the general population, and those who are members of a church tend to be members of a liberal denomination. The decision to enter a scientific field of study, especially the natural and social sciences, appears to be somewhat guided by religious beliefs, but scientists report that their religious beliefs are not influenced by their chosen profession. Also, those scientists who are at the top of their chosen field appear to be much less religious than the “average” scientist.
Findings in studies correlating religious beliefs and intelligence are mixed and unclear. As seen in part four, there is a clear correlation between lower religiosity and higher intelligence in the studies on a group of 1930s adolescent Jewish boys and for highly intelligent adults, but no relationship found in a more recent studies of adolescent Christian boys or college students. Methodological problems plague some of the major, large scale studies in this area, casting doubt on whether or not they were even measuring religiosity and/or intelligence. Some studies found higher college entrance exam scores for those who were lower measures of religiosity, while others found no relationship between the two. The extreme range of these studies’ measures, variables of interest, subjects, and publication dates makes synthesis of the literature difficult. Well-controlled, modern studies that use reliable and valid measures of both intelligence and various aspects of religiosity have shown either no relationship between the two or a very small relationship. More research on this subject is sorely needed with various populations in order to sort out potential mediating variables.
Synthesizing the above information allows us to hypothesize about the relationships among the studied variables. It seems clear that, at least in the U.S., fundamentalist religious beliefs hamper someone’s ability to obtain an education, particularly at the collegiate level. This could be via choice (e.g., your church’s teaching dismiss the “worldly” institutions of higher learning and leaders discourage attendance) or via a lack of skills necessary to succeed in higher education (e.g., you may have been home schooled in a way that discouraged development of – or purposefully avoided – math or science skills that become highly important in college entrance exams). This combined with a negative attitude towards scientific findings that may contradict the teaching of the Christian Bible if it is taken literally, seems to be at least partially the cause of so few of those engaged in scientific careers. These differences in education could also be partially the blame for the slightly lower overall intelligence among the religious found in some research, although this is very inconsistent.
My assertion, based on the above data and hypotheses, is that any intelligence differences seen between religious and non-religious persons is the result of educational and socioeconomic differences, not the result of some innate difference in intelligence. Therefore, if groups of theists and non-theists of the same educational and socioeconomic levels were compared on standard, individually administered intelligence tests, I think that there would be no group differences. This is, of course, just a hypothesis as of yet…but I will begin large-scale data collection this fall to test it out. For science!
Someone is born into a religious family, and then later deconverts and becomes a non-theist. At what point did their intelligence increase? Was it with their deconversion? Did he/she became an atheist and get smarter? Did he/she get smarter suddenly, which then caused the deconversion?
Obviously, this is a ludicrous question. It is especially odd given that we know people’s IQ scores are relatively stable from age five to adulthood (at least on standardized intelligence tests). Something else must be driving any noted intelligence differences. While I think that it is education, there are other variables in some of the reviewed studies (the personality factor of openness, for example) that must also be account for in any model. My upcoming research project will examine a host of demographic, religious, cognitive, and personality variables to find out which (alone or in combination) are most predictive of intelligence. You’ll find the results out here first…in about a year or so.
(Many thanks to Julie White for allow the adaptation of her thesis – which I supervised – into this series.)