Omissive Implicature

In some contexts, not saying S generates a conversational implicature: that the speaker didn't have sufficient reason, all things considered, to say S. I call this an omissive implicature. Standard ways of thinking about conversational implicature make the importance and even the existence of omissive implicatures somewhat surprising. But I argue that there is no principled reason to deny that there are such implicatures, and that they help explain a range of important phenomena. This paper focuses on the roles omissive implicatures play in Quantity implicatures—in particular, in solving the symmetry problem for scalar implicatures—and on the political and social importance of omissions where apologies, objections, or other communicative acts are expected or warranted.