Religious belief has often been labelled as “irrational belief”; however, in The rationality of heuristic religious belief, Wood (2012) proposed that religion could be understood as a set of heuristic devices that brings sub-optimal solutions to a complex and uncertain world. Wood’s philosophical argument successfully reframed rationality from an adaptive perspective, evaluating whether or not such belief increase adaptability in a natural or social environment; however, since his arguments focused on philosophical issues, there is a need for further investigation with empirical studies and theoretical modeling. In the last few decades, studies in the cognitive and evolutionary science of religion have further accumulated findings to support the view of ‘religion as a set of adaptive heuristic devices.’ Here, we review both the empirical and theoretical literature on religion that could support the adaptive rationality of religious beliefs, specifically focusing on three topics: the adaptive aspects of superstitions, belief in supernatural agents, and rituals. Collectively, findings from these areas support Wood’s view that religion can be rational in a sense of adaptation to ecological and social environments. We also discuss ongoing debates over the replicability of findings in the field and encourage further studies to perform more robust tests of the hypothesis.
