Michael McCourt

This dissertation asks how we should understand the distinction between semantic and pragmatic aspects of linguistic understanding within the framework of mentalism, on which the study of language is a branch of psychology. In particular, I assess a proposal on which the distinction between semantics and pragmatics is ultimately grounded in the modularity or encapsulation of semantic processes. While pragmatic processes involved in understanding the communicative intentions of a speaker are non-modular and highly inferential, semantic processes involved in understanding the meaning of an expression are modular and encapsulated from top-down influences of general cognition. The encapsulation hypothesis for semantics is attractive, since it would allow the semantics-pragmatics distinction to cut a natural joint in the communicating mind. However, as I argue, the case in favor of the modularity hypothesis for semantics is not particularly strong. Many of the arguments offered in its support are unsuccessful. I therefore carefully assess the relevant experimental record, in rapport with parallel debates about modular processing in other domains, such as vision. I point to several observations that raise a challenge for the encapsulation hypothesis for semantics; and I recommend consideration of alternative notions of modularity. However, I also demonstrate some principled strategies that proponents of the encapsulation hypothesis might deploy in order to meet the empirical challenge that I raise. I conclude that the available data neither falsify nor support the modularity hypothesis for semantics, and accordingly I develop several strategies that might be pursued in future work. It has also been argued that the encapsulation of semantic processing would entail (or otherwise strongly recommend) a particular approach to word meaning. However, in rapport with the literature on polysemy—a phenomenon whereby a single word can be used to express several related concepts, but not due to generality—I show that such arguments are largely unsuccessful. Again, I develop strategies that might be used, going forward, to adjudicate among the options regarding word meaning within a mentalistic linguistics.