Broad supernatural punishment but not moralizing high gods precede the evolution of political complexity
Supernatural belief presents an explanatory challenge to evolutionary theorists -- it is both costly and prevalent. One influential functional explanation claims that the imagined threat of supernatural punishment can suppress selfishness and enhance cooperation. Specifically, morally concerned supreme deities or 'moralising high gods' have been argued to reduce free-riding in large social groups, enabling believers to build the kind of complex societies that define modern humanity. Previous cross-cultural studies claiming to support the moralising high god hypothesis rely on correlational analyses only and do not correct for the statistical non-independence of sampled cultures. Here we use a Bayesian phylogenetic approach with a sample of 96 Austronesian cultures to test the moralising high god hypothesis as well as an alternative supernatural punishment hypothesis that allows punishment by a broad range of moralising agents. We find evidence that broad supernatural punishment drives political complexity, whereas moralising high gods follow political complexity. This suggests that the concept of moralising high gods diffused as part of a suite of traits arising from cultural exchanges between complex societies. Our results show the power of phylogenetic methods to address long-standing debates about the origins and functions of religion in human society.