How normative is implicature

In Implicature, I explained H.P. Grice's term “implicature,” and illustrated the practical and theoretical importance of the phenomenon it denotes. I then argued that the Gricean theory designed to explain and predict conversational implicatures, and describe how they are understood, is a near complete failure. In particular, I argued that implicatures are never derivable from conversational principles in the way Grice required, and do not exist in virtue of the satisfaction of Grice's cooperative presumption, determinacy, or mutual knowledge conditions. The root of the problem, I argued, is the intentionality of speaker implicature and the conventionality of sentence implicature.Jennifer Saul and Mitchell Green have suggested that my objections missed their target because Grice's conception of implicature was normative in crucial ways. Their suggestions are attractive and potentially fruitful. Nevertheless, I will present evidence that Grice did conceive of speaker implicature as a form of speaker meaning, and therefore as a matter of speaker intention. More importantly, I will argue that making Grice's theory normative in the ways Saul and Green suggest would not enable it evade the most serious problems I raised.