A Formal Ontology of Properties

A common problem of ontologies is that their taxonomic structure is often poor and confusing. This is typically exemplified by the unrestrained use of subsumption to accomplish a variety of tasks. In this paper we show how a formal ontology of unary properties can help using the subsumption relation in a disciplined way. This formal ontology is based on some meta-properties built around the fundamental philosophical notions of identity, unity, essence, and dependence. These meta-properties impose some constraints on the subsumption relation that clarify many misconceptions about taxonomies, facilitating their understanding, comparison and integration.