It is difficult to characterize “religion” as a form of knowledge because the set of practices with which the term is normally associated share little more than the capacity to maintain complex social relations over large chunks of space and time without a need for the modern nation state. In this respect, religions are the original non-governmental organizations (NGOs). As for the existence of some unique religious experience, William James had already put paid to that idea in 1902 by demonstrating that suitably “numinous” experience could be reliably induced by pharmaceutical means. (Given the cross-cultural prevalence of drug use, the so-called “world religions” would then seem to cover social practices that valorize the drug-free induction of numinous experience.) As for a belief in God, some religions, like Buddhism, are formally atheistic, while others, like Hinduism, treat God and nature as coextensive. (See naturalism.)

Not surprisingly, then, the canonical list of world religions came into being in the second half of the nineteenth century, as sociologists and anthropologists sought criteria to mark the transition from traditional to modern society. Perhaps the least prejudicial definition of religion – one that neither demeans nor mystifies its cognitive character – is that it is the systematic social embodiment of a metaphysical worldview. In this respect, any set of beliefs becomes a religion once they constitute the medium through which people live their lives.