Relevance and Utility in an Argumentative Framework: An Application to the Accommodation of Discourse Topics

We will focus in our paper on positions (1) and (3). A plausible candidate for a linguistic phenomenon that can be successfully modeled by a subset of game-theory is argumentation (cf. Ducrot (1980)). Argumentation concerns aspects of the meaning of sentences (words) that are not reducible to truth conditions. As such, one may ask whether these aspects are properly grammatical (i.e., encoded in the linguistic system), or pertain to the realm of pragmatics (i.e., contextual effects). In order to sort these things out, we investigate the link between the notions of relevance (in a theory of argumentation, as implemented in Merin’s decision-theoretic pragmatics) and the notion of (expected) utility in a game-theoretical framework of pragmatics. Crucially, our aim is to see if those two notions can and should be unified, which can only mean that relevance should be reduced to the expected utilities of the discourse participants — which would bring us to position (1), above. We will present arguments against such a move. To illustrate our point, we will study the accommodation of discourse topics in dialogues. We will show that relevance in an argumentative sense can easily be linked to the establishment of a discourse topic, since both notions are meant to relate to the point of discourse or to what the discourse is all about.