Reference: Fikes, R.; Farquhar, A.; & Rice, J. Tools for Assembling Modular Ontologies in Ontolingua. Knowledge Systems Laboratory, April, 1997.
Abstract: The Ontolingua ontology development environment provides a suite of ontology authoring tools and a library of modular, reusable ontologies. The environment is available as a World Wide Web service and has a substantial user community. The tools in Ontolingua are oriented toward the authoring of ontologies by assembling and extending ontologies obtained from thea library. In this paper, we describe Ontolingua's formalism for combining the axioms, definitions, and words (non-logical symbols) of multiple ontologies. We also describe Ontolingua's facilities that enable renaming of wordsnon-logical symbols from multiple component ontologies and that provide unambiguous mapping between words and text strings disambiguate symbol references during input and output. These features of Ontolingua support cyclic inclusion graphs and enable users to extend ontologies in multiple ways such as adding simplifying assumptions and extending the domains of polymorphic operators.
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