What is meaning, and how is it communicated? Paul Grice’s formulations of speaker meaning (Grice, 1957) and conversational implicature (1975) pave the way to answer those questions. In a nutshell, Grice demonstrates that our intuitions about the distinction between what is said and what is communicated can be explained in terms of communicative intentions. Unfortunately, his theory lacks psychological plausibility, and it fails to give an adequate explanation of how hearers comprehend a speaker’s communicative intention. To address these shortcomings, some theorists—namely, Sperber and Wilson (1986) and Richmond Thomason (1987)—have attempted to provide explanatorily powerful accounts of the comprehension process that are more firmly grounded in cognitive psychology and computer science. My research paper draws from Stephen Levinson (1989) to argue that Sperber and Wilson’s attempt to ground pragmatics in cognitive psychology is commendable, but that their relevance theory relies on circular reasoning and ex post facto explanations. Contrastingly, Thomason’s accommodation-based theory of comprehension is explanatorily powerful and psychologically plausible, but more research needs to be done to test it.