Metalevel and temporal reasoning in KNOWBEL: features and implementation

General-purpose knowledge representation systems serve two important purposes. First, such a system allows a knowledge engineer to model a new domain without being hampered by some special-purpose mechanism and without having to invent new tools. Second, knowledge stored in a general-purpose system becomes a resource that can be utilized by many users and applications within an organization. Three important requirements on such systems are that they be extensible and that they allow control of inference and temporal reasoning. A description is presented of the language features provided to meet these requirements and the mechanisms that are used to implement them efficiently in the KNOWBEL knowledge representation system