Abstract: CYC: A Case Study in Ontological Engineering
B. J. Copeland
University of Canterbury
Lenat's CYC is the severest test to date of the declarative
paradigm of knowledge representation and of traditional AI's 'physical
symbol system hypothesis'. Lenat and Guha describe CYC as 'mankind's first
foray into large-scale ontological engineering'. In designing CYC Lenat
and Guha have attempted to solve traditional philosophical problems in
ontology, epistemology, and logic. This paper reviews four areas that have
been extensively documented by Lenat and Guha: the problem of the nature
of substance; the problem of causality; the frame problem; and the problem
of reasoning within an inconsistent theory or set of beliefs. The
solutions to these problems that Lenat and Guha offer turn out to be
disappointingly weak. Lenat's prediction that he will produce 'a system
with human-level breadth and depth of knowledge' by the early years of
next century betrays a failure to appreciate the sheer difficulty of the
ontological, logical and epistemological problems that he has taken on.