- From: fensel <dieter.fensel@ontotext.com>
- Date: Thu, 07 Apr 2011 20:29:05 +0200
- To: Pat Hayes <phayes@ihmc.us>,fensel <dieter.fensel@ontotext.com>
- Cc: Pierre-Antoine Champin <pierre-antoine.champin@liris.cnrs.fr>, "nathan@webr3.org" <nathan@webr3.org>,RDF WG <public-rdf-wg@w3.org>
Hi Pat, sure. Everything you are writing is correct. However: - I do not think that the problem of RDF is that it does not provide enough. For a base layer were other languages are layered on top it provides actually quite a lot of features. Bags, collections, and lists, reification, and statements in the language over other language statements etc. Frankly, I think a better job would have to keep RDF as simple and basic as possible. So I would rather love to see a simplification than an enrichment of RDF. - Why include stuff in the very base layer of the semantic web that you know that other languages will forbid to keep inference tractable. - Proper equality on the web is a fascinating research question and I expect more and more PhDs on it. Currently its complexity is still mostly neglected or "solved" very simplistic as in OWL. Again, I wonder whether a research issue should already be standardized at the most basic level. Many people use owl:sameAs because there is nothing better around for their purpose (similar SKOS stuff comes without reasoning support). I do not think they are really happy with it and calling it rdf:sameAs will not solve their problem either. Dieter At 18:22 06.04.2011, Pat Hayes wrote: >On Apr 6, 2011, at 10:19 AM, fensel wrote: > > > At 13:39 06.04.2011, Pierre-Antoine Champin wrote: > >> On 04/06/2011 05:14 AM, Pat Hayes wrote: > >> > We might want to think about incorporating some version of sameAs > >> > into RDFS, as this seems to be fundamental to linked data and also > >> > widely misused. Having the real meaning of equality exposed in the > >> > RDF standard itself might be doing the world a favor. (?) > >> > >> +1e99 > > > > I think this may be a very bad idea. You would force all languages > > layering on top of RDF to include equality. > >It depends what you mean by 'include'. A language based on RDF can >always declare that it will use some other term and refuse to accept >the RDF one, just as OWL uses owl:Thing rather than >rdf:Resource. BUt it would be more useful and more in the spirit of >interoperability to use the same term and just acknowledge that it >is not using all the intended meaning of that term. > > > There are reasons > > to prevent equality because it turns unification from a syntactical > > operation into reasoning. > >Only if you claim to be logically complete. A reasoner can always >just ignore the equalities, or use them in a limited but useful way. >Reasoners are not *obliged* to squeeze every last drop of meaning >from all the RDF they encounter. Still, the RDF means what it means :-) > >Pat > > > > > Dieter > > > >------------------------------------------------------------ >IHMC (850)434 8903 or (650)494 3973 >40 South Alcaniz St. (850)202 4416 office >Pensacola (850)202 4440 fax >FL 32502 (850)291 0667 mobile >phayesAT-SIGNihmc.us http://www.ihmc.us/users/phayes
Received on Thursday, 7 April 2011 18:35:42 UTC