Abstract

The primary function of language is communication. We use the tools of situation theory and game theory to develop a definition and model of communication between rational agents using a shared situated language. ;A central thesis of this dissertation is that the key feature of situated communication that enables agents to derive content from meaning is a special type of logical inference called a strategic inference. ;The model we develop, called the Strategic Discourse Model, looks at a single strategic inference. An essential element of a strategic inference is that the content depends on the sentence uttered and on the embedding circumstances. This includes the private and public information and beliefs of the agents, their goals and intentions, and crucially, the other sentences the speaker might have uttered but chose not to. A complete model of communication involves a system of simultaneous strategic inferences. ;When the strategic interaction between two agents is common knowledge between them, that is, when it is a game, the information transfer is a communication. The content communicated is given by the solution to the game. This analysis formalizes Grice's ideas on nonnatural meaning within a situation-theoretic framework. A consequence of our situated analysis is that agents do not need to have the complex and infinite set of nested intentions postulated by the Gricean approach. A simple intention to communicate is all that is required, the ambient game doing the rest of the work. ;This model has many applications. Problems like resolving ambiguity, determining reference, inferring implicatures and indirect speech acts fall within its scope. As one application, we outline a new theory of names and definite descriptions. This account builds upon Russell and Strawson, and Barwise and Perry. The basic idea is that names and descriptions can both be used in various ways circumscribed by an ontological and a communicative constraint. This offers a new solution to the puzzle of informative identity statements and clarifies the referential-attributive distinction. It suggests an approach to the concept of representation. ;An underlying theme is to synthesize situation theory and game theory