Laconic discourses and total eclipses: abduction in DICE

The goal of this chapter is demonstrate one particular use of abduction in the processing of natural language discourse. DICE (Discourse In Commonsense Entailment) can be used to model both interpretation and generation. For interpretation, it uses defeasible deduction to determine the discourse structures and event structures underlying multisentential texts. For generation, it uses abduction to build up specifications of texts from underlying event structures. Thus, abduction is the primary mechanism of generation, and has a smaller role to play in interpretation. To demonstrate how the approach works in generation and interpretation, we introduce two exemplary problems, which involve brevity and accommodation respectively. We then outline a formal model of implicature, and indicate how it is recruited for interpretation by deduction and generation by abduction. We show how brief but accurate discourses can be generated under this model, and the