On Inheritance in Knowledge Representation

Abstract

This paper examines the problem of inheritance in knowledge representation. Research In the formalluton of knowledge h.s resulted in a small number of knowledge classes and associated inheritance relatione, e.a., tNSTANCl, IS-A, DBIIOTHERC, PERSPECTIVE, VltTUAl.catrlt etc. (8rachman, 1977; Fahlman, 1977; Hayes, 1971a Levesque A Mylopoloua, 1978). The process of inheritance is defined by the procedures that m these inheritance relatione. Thla paper proposes that: 1) in some cases inheritance between concepts is i.di<>lyr&ercltic and does 021. fit predefined Inheritance relations, 2) learning and discovery systems require Information on ~ and m one concept Wll d.erl.11ed. from another, which again Is not represented in standard Inheritance relations, and 3) current methods of speclfylna Inheritance modification and similarity mappings are complex to specify and understand. Consequently, a declarative approach to Inheritance and similarity specificaton Is presented aa a aolutlon to the above problema.