Where is the justificatory boundary between a true belief’s not being knowledge and its being knowledge? Even if we put to one side the Gettier problem, this remains a fundamental epistemological question, concerning as it does the matter of whether we can provide some significant defence of the usual epistemological assumption that a belief is knowledge only if it is well justified. But can that question be answered non-arbitrarily? BonJour believes that it cannot be – and that epistemology should therefore abandon the concept of knowledge. More optimistically, this paper does attempt to answer that question, by applying – and thereby refining – a non-absolutist theory of knowledge.