There is considerable philosophical dispute about what it takes for an action to be evil. The methodological assumption underlying this dispute is that there is a single, shared folk conception of evil action deployed amongst culturally similar people. Empirical research we undertook suggests that this assumption is false. There exist, amongst the folk, numerous conceptions of evil action. Hence, we argue, philosophical research is most profitably spent in two endeavours. First, in determining which (if any) conception of evil action we (...) have prudential or moral (or both) reason to deploy, and second, in determining whether we could feasibly come to adopt that conception as the single shared conception given our psychological make-up and the content of the conceptions currently deployed. (shrink)