Ontologies

This chapter introduces the concept of ontology and ontological engineering in a broader perspective than simply focusing on agents. The concept of ontology is difficult to explain because it has different meanings for different categories of people, in particular for philosophers, and for software engineers. According to the Catholic Encyclopedia the term Ontology was introduced by von Wolff in the eighteen century to distinguish a branch of metaphysics, the general metaphysics, from the special metaphysics which included cosmology, psychology, and theodicy. An ontology is a repository of concepts structured by relations describing the world. An interesting use of an ontology is in the building of artificial systems, like databases, knowledge-based systems, or natural language understanding systems. Building an ontology for a particular domain provides powerful clarification and can be used to improve person to person communications. The web environment needs ontologies to improve the efficiency of search engines.