Semantics and Pragmatics in the ELTA Dialogue Project

This paper 1 describes work in progress concerning the semantic and pragmatic interpretation of utterances in human-computer natural language information dialogues, as developed in the ELTA project at Tilburg University. This project aims at developing and applying an integrated approach to semantic and pragmatic interpretation of dialogue utterances, where the application is sought in the form of a dialogue system capable of acting as a cooperative partner in an information dialogue. The ELTA project continues a line of work in language understanding, dialogue studies, and designing intelligent interactive systems. A salient feature of the ELTA approach is that it considers semantic (truthconditional) and pragmatic (speech act) interpretation to be fundamentally context-based; the resolution of ambiguity and vagueness, often considered to be the main task of natural language interpretation, is not approached as a goal in itself, but as something to be done only as demanded and to the extent required by the context of the application. In this paper we will be concerned with three issues in the study of dialogues: (1) under-speciication in the semantic content of dialogue utterances; (2) the communicative functions of dialogue utterances as context-changing functions, and (3) the formal modelling of dialogue context.