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Standard OIL

Standard OIL extends OIL-Lite with the possibility to define instances of classes and roles. These definitions are of the form (instance-of $ i$ $ C_1,\ldots,C_n$) and (related $ S$ $ i$ $ j$), where $ C$ (possibly subscripted) is a class expression, $ S$ is a slot name and $ i$ and $ j$ are individual names. An axiom (instance-of $ i$ $ C_1,\ldots,C_n$) is equivalent to (instance-of $ i$ ( $ C_1~\key{and}~\ldots~\key{and}~C_n$). These axioms are simply treated as ``syntactic sugar'' for axioms of the form

covered-by (one-of $ i$) $ C$

(i.e., $ P_i \sqsubseteq C$), and

covered-by (one-of $ i$) (slot-constraint $ S$ has-value (one-of j))

(i.e., $ P_i \sqsubseteq \ensuremath{\exists S . P_j}$) respectively.

Ian Horrocks 2000-09-10