Is an upper ontology intended as a foundation ontology for a variety of computer information processing systems. SUMO defines a hierarchy of classes and related rules and relationships. These are expressed in a version of the language SUO-KIF which has a LISP-like syntax. A mapping from WordNet synsets to SUMO has been defined. Initially, SUMO was focused on meta-level concepts (general entities that do not belong to a specific problem domain), and thereby would lead naturally to a categorization scheme for encyclopedias. It has now been considerably expanded to include a mid-level ontology and dozens of domain ontologies. SUMO is organized for interoperability of automated reasoning engines.
F.31.3 Key characteristics
A natural language ontology that supports higher order types (see ‘class’ and ‘set’ below)
F.31.4 Relevant Extracts
Extract 1 – Collection, Class and Set
(documentation Collection EnglishLanguage "Collections have members like Classes, but, unlike Classes, they have a position in space-time and members can be added and subtracted without thereby changing the identity of the Collection. Some examples are toolkits, football teams, and flocks of sheep.")
(documentation Class EnglishLanguage "Classes differ from Sets in three important respects. First, Classes are not assumed to be extensional. That is, distinct Classes might well have exactly the same instances. Second, Classes typically have an associated `condition' that determines the instances of the Class. So, for example, the condition `human' determines the Class of Humans. Note that some Classes might satisfy their own condition (e.g., the Class of Abstract things is Abstract) and hence be instances of themselves. Third, the instances of a class may occur only once within the class, i.e. a class cannot contain duplicate instances.")
(documentation Set EnglishLanguage "A SetOrClass that satisfies extensionality as well as other constraints specified by some choice of set theory. Sets differ from Classes in two important respects. First, Sets are extensional – two Sets with the same elements are identical. Second, a Set can be an arbitrary stock of objects. That is, there is no requirement that Sets have an associated condition that determines their membership. Note that Sets are not assumed to be unique sets, i.e. elements of a Set may occur more than once in the Set.")
NB: Collections of collections are fusion of their members and so do not ascend a type.
Continue to Appendix G: Prior ontological commitment literature