The chapter focuses on the interpretation of a group of expressions which the authors Axel Barceló and Robert Stainton term ‘quasi-factives’, an area in which the recurring issue of the relative contributions of linguistically encoded meaning and pragmatic inference is especially striking. In line with Deirdre Wilson’s early work on presupposition (Wilson 1975), they argue that the factive conclusions which these expressions seem to support are not to be explained semantically. Rather, they are components of the speaker’s meaning and their derivation by the addressee depends on the kind of cost–benefit trade-off that is central to relevance theory.