Objectives

This section discusses how inheritance is employed in knowledge representation systems. It covers the general structure of inheritance networks and deals with problems that may arise due to the non-monotonic reasoning involved. Further, it shows how the semantics of an inheritance lattice may be rendered using first order logic.

Points to emphasize

Hints

Inheritance, both in the form of semantic nets and relations between frames, has a long standing tradition in the artificial intelligence community. In practice, many interesting applications have been developed by integrating reasoning capabilities with object-oriented features. See, for example,  [Harmon93]. We still, however, need a unifying framework, encompassing programming and knowledge representation in an adequate way. See  [LNS90].

Questions

    .so q1

Comments

The interplay between modeling and reasoning is an intriguing issue. For example, how would you characterize the refinement relation between objects incorporating rules? The most likely way, in accord with the refinement rules for methods, is to employ a criterion of theory extension or subsumption.