- From: Jonathan Borden <jonathan@openhealth.org>
- Date: Wed, 17 Apr 2002 08:45:21 -0400
- To: Jeremy Carroll <jjc@hplb.hpl.hp.com>
- CC: www-webont-wg@w3.org
Jeremy Carroll wrote: [snip] . > > Example: > > The RDF document: > > <rdf:Description rdf:about="#John"> > <rdf:type rdf:resource="#Student"> > <rdf:type rdf:resource="#Employee"> > </rdf:Description> > > understood with rdf:type denoting set membership, would, under almost all > set theories, entail #John being a member of the intersection of #Student > and #Employee. > In daml+oil this is said: > > <rdf:Description rdf:about="#John"> > <rdf:type> > <daml:class> > <daml:intersectionOf rdf:parseType="daml:collection"> > <daml:class rdf:ID="Employee"/> > <daml:class rdf:ID="Student"/> > <daml:intersectionOf> > </daml:class> > </rdf:type> > </rdf:Description> > > If we leave the daml class expression: > > <rdf:RDF> > <daml:class> > <daml:intersectionOf rdf:parseType="daml:collection"> > <daml:class rdf:ID="Employee"/> > <daml:class rdf:ID="Student"/> > <daml:intersectionOf> > </daml:class> > </rdf:RDF> > > as unasserted then OWL can assign a meaning to this expression wholly > independently of RDF. > > Have I got it? How does this particular example demonstrate a problem? Why should this convince DanC? One of PeterPS's examples used a paradoxical class i.e. a member of itself. Is there a similar class that does not depend on the use of the 'Q's? e.g. would something like: <ont:Class rdf:ID="foo"> <ont:unionOf rdf:parseType="ont:collection"> <ont:Class rdf:about="#foo"/> <ont:Class rdf:about="#bar"/> </ont:unionOf> </ont:Class> be a problem? or <ont:Class rdf:ID="foo"> <ont:disjointUnionOf rdf:parseType="ont:collection"> <ont:Class rdf:about="#foo"/> <ont:Class rdf:about="#bar"/> </ont:disjointUnionOf> </ont:Class> I'm just guessing, but the example should demonstrate a paradox - right? Jonathan
Received on Wednesday, 17 April 2002 08:50:09 UTC