We review Potts’ influential book on the semantics of conventional implicature (CI), offering an explication of his technical apparatus and drawing out the proposal’s implications, focusing on the class of CIs he calls supplements. While we applaud many facets of this work, we argue that careful considerations of the pragmatics of CIs will be required in order to yield an empirically and explanatorily adequate account.

Grice’s distinction between what is said and what is implicated has greatly clarified our understanding of the boundary between semantics and pragmatics. Although border disputes still arise and there are certain difficulties with the distinction itself (see the end of §1), it is generally understood that what is said falls on the semantic side and what is implicated on the pragmatic side. But this applies only to what is..

I argue that conventional implicatures embed in logical compounds, and are non-truth-conditional contributors to sentence meaning. This, I argue has significant implications for how we understand truth, truth-conditional content, and truth-bearers.

Are all instances of the T-schema assertable? I argue that they are not. The reason is the presence of conventional implicature in a language. Conventional implicature is meant to be a component of the rule-based content that a sentence can have, but it makes no contribution to the sentence's truth-conditions. One might think that a conventional implicature is like a force operator. But it is not, since it can enter into the scope of logical operators. It follows that the semantic (...) content of a sentence is not given simply by its truth-conditional content. So not all instances of the T-schema are assertable in the relevant sense. Consequently, there is a strong case to be made against truth-conditional semantics of the disquotational variety and deflationism about truth. (shrink)

Scalar implicatures depend on alternatives in order to avoid the symmetry problem. I argue for a structure-sensitive characterization of these alternatives: the alternatives for a structure are all those structures that are at most as complex as the original one. There have been claims in the literature that complexity is irrelevant for implicatures and that the relevant condition is the semantic notion of monotonicity. I provide new data that pose a challenge to the use of monotonicity and that support the (...) structure-sensitive definition. I show that what appeared to be a problem for the complexity approach is overcome once an appropriate notion of complexity is adopted, and that upon closer inspection, the argument in favor of monotonicity turns out to be an argument against it and in favor of the complexity approach. (shrink)

We define a notion of projective meaning which encompasses both classical presuppositions and phenomena which are usually regarded as non-presuppositional but which also display projection behavior—Horn’s assertorically inert entailments, conventional implicatures (both Grice’s and Potts’) and some conversational implicatures. We argue that the central feature of all projective meanings is that they are not-at-issue, defined as a relation to the question under discussion. Other properties differentiate various sub-classes of projective meanings, one of them the class of presuppositions according to Stalnaker. (...) This principled taxonomy predicts differences in behavior unexpected on other models among the various conventional triggers and conversational implicatures, while holding promise for a general, explanatory account of projection which applies to all the types of meanings considered. (shrink)