André Valente and Joost Breuker
An important issue in the newborn discipline of ontological engineering is the construction of libraries of ontologies which are designed for maximum reusability. Van Heijst et. al. suggested that a central part of ontology libraries is the definition of what they called a core ontology, containing elements that are as generic and method-independent as possible. However, their specification of how these core ontologies should be constructed is highly pragmatical, and leaves many problems unresolved. In this article we propose and discuss a number of specific principles for the construction of core ontologies. We demonstrate the advantages of these principles using as an example a core ontology we have built for the domain of law. Several conclusions about the construction of ontology libraries based on core ontologies are drawn.