The Theoretical Status of Ontologies in Natural Language Processing

This paper discusses the use of `ontologies' in Natural Language Processing. It classifies various kinds of ontologies that have been employed in NLP and discusses various benefits and problems with those designs. Particular focus is then placed on experiences gained in the use of the Upper Model, a linguistically-motivated `ontology' originally designed for use with the Penman text generation system. Some proposals for further NLP ontology design criteria are then made.