John M. Levine
This paper gives an overview of a natural language dialogue system called PRAGMA. This system contains a number of novel and important features, as well as integrating previous work into a unified mechanism. The most important advance that PRAGMA represents compared with previous systems is the high degree of bidirectional@ employed in its design. A single grammar is used for interpretation and generation, and the same knowledge sources are used for plan recognition and response generation. The system is also flexible, in that it generates useful extended responses, not only to queries which allow the user’s plan to be inferred, but also to queries which do not allow this.