Conventional implicatures , a distinguished class of meanings ∗

The history of conventional implicatures is rocky, their current status uncertain. It seems wise to return to their source and start fresh, with an open-minded reading of the original definition (Grice, 1975) and an eye open for novel support. Suppose the textbook examples (therefore, even, but and synonyms) disappeared. Where would conventional implicatures be then? This paper argues that they would still be widely attested, and moreover that if we move a few years forward from their genesis, we find in Karttunen and Peters’ (1979) multidimensional semantics the basis for an ideal description logic. Conventional implicatures were born into neglect. Early in ‘Logic and conversation’, Grice advances the term and a definition, but primarily to set such meanings aside. The pragmatic theory of Grice 1975 takes the form of an overarching cooperative principle and a set of maxims. Together, these help to shape both linguistic and nonlinguistic social interactions. The theory is thus tailored to describing conversational implicatures, a class of nonlexical meanings whose presence and nature are contextually determined and negotiable. In contrast, conventional implicatures trace back to individual lexical items and have the force of entailments. General principles of cooperative social interaction are of little