- From: Graham Klyne <Graham.Klyne@MIMEsweeper.com>
- Date: Fri, 14 Jun 2002 17:36:59 +0100
- To: Dan Connolly <connolly@w3.org>
- Cc: patrick hayes <phayes@ai.uwf.edu>, w3c-rdfcore-wg@w3.org
At 08:15 AM 6/14/02 -0500, Dan Connolly wrote: >Second, would somebody please show how this helps with layering? > >i.e. show how it relates to the example in... > ># Layering OWL on RDF: the case for unasserted triples >Jonathan Borden (Thu, May 30 2002) >http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2002May/0145.html The example in the referenced document uses additional statements: owl:List rdf:type rdf:Unasserted . owl:first rdf:type rdf:Unasserted . owl:rest rdf:type rdf:Unasserted . owl:nil rdf:type rdf:Unasserted . but Guha has explained that that approach is non-monotonic. The revised proposal simply defines triples using certain URIs to be unasserted, regardless of any other triples that may appear in the graph, so there's no question that adding a new triple makes a truth out of a falsehood. Referring to my suggestion, the properties used above as owl:List, owl:first, owl:rest, owl:nil would be given URIs of the form: http://www.w3.org/2002/06-rdf-unasserted#List http://www.w3.org/2002/06-rdf-unasserted#first http://www.w3.org/2002/06-rdf-unasserted#rest http://www.w3.org/2002/06-rdf-unasserted#nil Actually, I don't think List and nil need to be given this unasserted treatment. Indeed, in the case of nil, I think it may be a serious error, because there would be no meaning associated with statements like: ex:someResource ex:someListValuedProperty unasserted:nil . #g ------------------- Graham Klyne <GK@NineByNine.org>
Received on Friday, 14 June 2002 12:51:00 UTC