Losing faith in the intelligence-religiosity link: New evidence for a decline effect, spatial dependence, and mediation by education and life quality

Research has shown negative intelligence-religiosity associations among both persons (Zuckerman, Silberman, & Hall [Personality and Social Psychology Review 17 (2013) 325-354]) and countries (Lynn, Harvey, & Nyborg [Intelligence 37 (2009) 11-15]). Nevertheless, it remains unclear if these associations are stable over time or explained by education, quality of human conditions (QHC), or spatial dependence. In Study 1, we re-analyzed Zuckerman et al.'s meta-analysis, and after controlling for sample differences, the negative intelligence-religiosity link declined over time. The intelligence-religiosity link was non-significant among samples using men, pre-college participants, grade point average, and those collected after 2010. Education also partially mediated the intelligence-religiosity link. In Study 2, we re-analyzed Lynn et al.'s data from 137 countries and found that QHC positively moderated and partially mediated the positive relation between IQ and disbelief in God; this link became non-significant after controlling for spatial dependence (i.e., the extent to which adjacent countries reflect statistically non-independent observations). Although the negative intelligence-religiosity link appears more robust across people than countries, multiple variables moderate or mediate its strength, and hence, limit its generalizability across time, space, samples, measures, and levels of analysis.