While 'belief' as an interiorized, propositional capacity may be universal, when discussing the domain of 'religion' it must be viewed as a trope, that is, as a particular and historically specific Western cultural idiom for expressing people's relationship to tradition. This idiom emphasizes the interiority of ethno-religious identity. Drawing on ethnographic material from the Akha of Northern Thailand and some other Asian societies, it is argued that while 'belief' as an interiorizing notion is relevant in some contexts, it is not at all relevant to Akha cultural discourse on the relationship to tradition. There, ethno-religious identity takes an exteriorized form. This finding is used to expose the assumption of interiority in the various anthropological approaches to religious belief, and its implications for discussions of scepticism and critical thought are explored.