- From: pat hayes <phayes@ai.uwf.edu>
- Date: Fri, 28 Jun 2002 01:12:46 -0500
- To: "Jeremy Carroll" <jjc@hplb.hpl.hp.com>
- Cc: w3c-rdfcore-wg@w3.org
>Pat > >I saw in > >http://lists.w3.org/Archives/Public/www-webont-wg/2002Jun/0178.html > >that you argued against Jos for the truth of basic set theoretic facts from >nothing. > >My range and domian rules seem to me to be of a similar truth status. I don't see that they are. In fact, your entailments aren't even valid, because two different classes can have the same class extension. I see range and domain as being particular individual classes 'attached' to a property. That attachment needn't be inherited under superset. So its not just a matter of asserting things with no antecedents (the closure rules already do a lot of that), but what things should be asserted at all. Pat >(There may >be a choice, and that choice depends upon how we regard the representation of >logical facts within the domain of discourse. Given that webont >wants to be able >to represent such facts without having to explicitly assert them, >then shouldn't >we be taking the same position in RDF Core too?) > >Jeremy > >> -----Original Message----- >> From: w3c-rdfcore-wg-request@w3.org >> [mailto:w3c-rdfcore-wg-request@w3.org]On Behalf Of Jeremy Carroll >> Sent: 26 June 2002 10:09 >> To: pat hayes >> Cc: w3c-rdfcore-wg@w3.org >> Subject: RE: MT RDFS closure rule bug? >> >> >> >> >> > >> > >Pat, >> > > >> > >don't we need RDFS closure rules that add range and domain constraints >> > >e.g. >> > > >> > >aaa [rdfs:range] yyy >> > >yyy [rdfs:subClassOf] zzz >> > > >> > >then add >> > > >> > >aaa [rdfs:range] zzz >> > > >> > > >> > >and similarly for rdfs:domain. >> > >> > NO. That would be disastrous for the datatyping and in any case not >> > make sense. Why do want them? >> > >> > >> >> We don't *want* them, they are just true! >> Or maybe I've been talking to Peter too much! >> >> Any interpretation of any >> >> > >aaa [rdfs:range] yyy >> > >yyy [rdfs:subClassOf] zzz >> >> >> is an interpretation of >> >> > >aaa [rdfs:range] zzz >> >> >> thus the closure rule holds. >> >> (Not) Proof: >> >> Ahh, it depends on rdfs:range not being in the domain of discourse. >> neglecting that little factette and invalidating the proof ... >> >> Whenever >> iii aaa jjj . >> then >> jjj [rdf:type] yyy . >> hence >> jjj [rdf:type] zzz . >> >> hence >> >> aaa [rdfs:range] zzz . >> >> == >> >> I smell danger. >> >> >> Jeremy >> >> >> >> >> >> -- --------------------------------------------------------------------- IHMC (850)434 8903 home 40 South Alcaniz St. (850)202 4416 office Pensacola, FL 32501 (850)202 4440 fax phayes@ai.uwf.edu http://www.coginst.uwf.edu/~phayes
Received on Friday, 28 June 2002 02:12:46 UTC