Information, relevance, and social decisionmaking: some principles and results of decision-theoretic semantics

I propose to treat natural language semantics as a branch of pragmatics, identified in the way of C.S. Peirce, F.P. Ramsey, and R. Carnap as decision-theory. The notion of relevance plays a key role. It is explicated traditionally, distinguished from a recent homophone, and applied in its natural framework of issue-based communication. Empirical emphasis is on implicature and presupposition. Several theorems are stated and made use of. Items analyzed include ‘or’, ‘not’, ‘but’, ‘even’, and ‘also’. I conclude on parts of mind. This paper submits an approach to meaning, with a focus on broadly nontruth-conditional aspects of natural language. Semantics is treated as a branch of pragmatics, identified as decision-theory in the way of C.S. Peirce, F.P. Ramsey, and of Rudolf Carnap in his later work. A key theoretical notion, distinguishable from, but intelligibly related to, information is the positive or negative relevance of a proposition or sentence to another. It is explicated in the probabilistic way familiar from Carnap and traditional in the philosophies of science and rational action. This makes it a representation of local epistemic context-change potential that is directional in a precisely specifiable sense and naturally related to utterers’ instrumental intentions. Relevance so defined is proposed as an explicans for Oswald Ducrot’s insightful ‘valeur argumentative’. In view of possible confusion among some students of language, it is contrasted with a more recent and idiosyncratic pretender to the appellation, due to Dan Sperber and Deirdre Wilson. The latter proposal turns out, at best, to paraphrase H.P. Grice’s non-directional concepts of ‘informativeness’ and ‘perspicuity’. (More informative designations are suggested for it, and for the eponymous linguistic doctrine emanating from parts of CNRS Paris and of UC London.)