Imported from Ontology on 2005-03-14
In philosophy, 'ontology' (from the Greek ων = being and λόγος = word/speech) is the most fundamental branch of metaphysics. It studies being or existence as well as the basic categories thereof — trying to find out what entities and what types of entities exist. Ontology has strong implications for the conceptions of reality.
Some philosophers, notably of the Platonic school, contend that all nouns refer to entities. Other philosophers contend that some nouns do not name entities but provide a kind of shorthand way of referring to a collection (of either objects or events). In this latter view, mind, instead of referring to an entity, instead refers to a collection of mental events experienced by a person; society, instead of referring to an entity, refers to a collection of persons with some shared characteristics; and geometry, instead of referring to an entity, refers to a collection of a specific kind of intellectual activity. Any ontology then must give an account of which words refer to entities, which do not, why, and what categories result. When one applies this process to nouns such as electrons, energy, promise, happiness, time, truth, causality, and god, ontology becomes fundamental to many branches of philosophy.
Ontology has as one of its basic questions: "What are the fundamental categories of being?" Different philosophers make different lists of such fundamental categories of being.
This highlights one of the problems of the philosophical approach — it relies on continued investigation of categories, and has no clear way to stop asking. Whereas, in theology and library science and artificial intelligence, one typically adopts a relatively stable foundation ontology. This reflects a larger cosmology and probably morals, aesthetic examples or stories; all of which can set foundational priorities. In theology this derives from a religion and its (relatively) stable doctrines.
Further examples of ontological questions include: