- From: Jos De_Roo <jos.deroo.jd@belgium.agfa.com>
- Date: Mon, 26 Aug 2002 02:11:01 +0200
- To: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>
- Cc: www-webont-wg@w3.org
> > [...] > > > > > > > Why should anyone care at all about the entailment rules? > > > > > > > > because > > > > > > > [...] > > > > > > OK, agreed, entailment can be related to *inference* rules. > > > > > > But why should I care whether ``no new existentials are introduced in the > > > [inference] rules''? > > > > OK, e.g. we can't have existentials in the conclusion that are > > in the domain of an owl:InverseFunctionalProperty because that > > property is simply not defined over it's whole range > > (lists in the range of e.g. owl:intersectionOf could contain a > > mix of resources being classes, properties, classes/properties > > and so many of such intersections simply don't exist and in > > general we can't give the list constraints in the premis) > > Why not? You mean, perhaps, that you can't. > > However, there is nothing to prevent one from writing an inference rule > like > > ?x rdf:type owl:Class . > ?y rdf:type owl:Class . > ?i rdf:type ?x . > ?i rdf:type ?y. > implies ?i rdf:type _:l . > _:l owl:intersectionOf [ ?x ?y ] . Why not having owl:intersectionOf defined for instances of rdf:Class and even instances of rdf:Property? They are sets, aren't they? -- , Jos De Roo, AGFA http://www.agfa.com/w3c/jdroo/
Received on Sunday, 25 August 2002 20:11:38 UTC