The Representation of Presuppositions Using Defaults

This paper is a first step towards the computation of an inference based on language use, termed presupposition. Natural languages, unlike formal languages, can be semantically ambiguous. These ambiguities are resolved according to pragmatic rules. We take the position that presuppositions are inferences generated from these pragmatic rules. Presuppositions are then used to generate the preferred interpretation of the ambiguous natural language sentence. A preferred interpretation can be circumvented by an explicit inconsistency. This paper discusses the appropriateness of using default rules (Reiter(1980)) to represent certain common examples of presupposition in natural language. We believe that default rules are not only appropriate for representing presuppositions, but also provide a formal explanation for a precursory consistency-based presuppositional theory (Gazdar(1979)).