- From: patrick hayes <phayes@ai.uwf.edu>
- Date: Mon, 24 Jun 2002 18:11:00 -0500
- To: Jan Grant <Jan.Grant@bristol.ac.uk>
- Cc: w3c-rdfcore-wg@w3.org
>Pat indicated at the F2F that entailments "accidentally" drawn would be >"harmless". RDF entailments, yes. >Can someone clear up this example for me? > >A: > <eg:foo1> <rdf:subPropertyOf> <dark:eg:foo2> . > <dark:eg:foo2> <rdf:subProperotyOf> <eg:foo3> . > > <eg:a> <eg:foo1> <eg:b> . > >B: > <eg:foo1> <rdf:subPropertyOf> <dark:eg:foo2> . > <dark:eg:foo2> <rdf:subProperotyOf> <eg:foo3> . > > <eg:a> <dark:eg:foo2> <eg:b> . > >C: > <eg:foo1> <rdf:subPropertyOf> <dark:eg:foo2> . > <dark:eg:foo2> <rdf:subProperotyOf> <eg:foo3> . > > <eg:a> <eg:foo3> <eg:b> . > > >Does A |= C? Does A |= B? B |= C? Yes: A|= C (by subproperty chaining and then the subproperty closure rule) No: A |= B (dark conclusion) B |= C (dark, ie missing, antecedent) However, notice that should be rdfs:subPropertyOf. To anticipate your next question: yes, one does have to be careful using darkened triples in RDFS hierarchical inferences (basically, any kind of transitivity implication, ie subPropertyOf and subClassOf.) What I claimed was that it was safe with RDF-valid reasoning (ie effectively, existential generalization). Pat -- --------------------------------------------------------------------- IHMC (850)322 0319 cell 40 South Alcaniz St. (850)202 4416 office Pensacola, FL 32501 (850)202 4440 fax
Received on Monday, 24 June 2002 19:11:03 UTC