Natural language is one of the more appealing ways by which people can interact with computers, but up to now its application has been severely constrained. We argue that to use natural language effectively, we must have both a deep understanding of the subject domain and a general-purpose reasoning capability. We illustrate the issues with SAP-QUEST, a proof-of-concept system for natural language question answering over a set of data sources for business enterprise applications, but the argument can be applied more generally to dialogue-style interfaces over a variety of subject domains.
