- From: Dan Connolly <connolly@w3.org>
- Date: 23 Apr 2002 18:14:17 -0500
- To: Ian Horrocks <horrocks@cs.man.ac.uk>
- Cc: Pat Hayes <phayes@ai.uwf.edu>, www-webont-wg@w3.org
On Tue, 2002-04-23 at 17:23, Ian Horrocks wrote: > On April 8, Pat Hayes writes: [...] > > so these issues seem largely irrelevant; whereas the inconvenience > > and artificiality of maintaining the restriction is a real barrier to > > deployment. There is no *semantic* reason for the distinction. > > W.r.t. the domains, the interaction between the concept language and > the built in datatype predicates is at best unpleasant and may even > lead to undecidability (no definitive result at present). I also don't > believe that this is "a real barrier to deployment" (can you show me > examples where users really need objects that are both individuals and > data values?). Fair question. It comes up quite a bit in my work. I don't make any claims about 'individuals'; but I need to have UnambiguousProperty's that take literal values. For example, U.S. states that have the same 2-letter postal code are the same state. So if I know :stateCode a ont:UnambiguousProperty. _:x :stateCode "KS". _:x :population "2688418". _:y :stateCode "KS". _:y :stateBird :WesternMeadowlark. then I should be able to conclude _:z :population "2688418". _:z :stateBird :WesternMeadowlark. Full details, with namespaces spelled out and all that, in: http://www.w3.org/2002/03owlt/sameStateP.rdf http://www.w3.org/2002/03owlt/sameStateC.rdf > I believe that a much bigger barrier to deployment > would be devising a language where complete (and perhaps even sound) > reasoners were difficult or impossible to build. Yes, well, we disagree on that. Perhaps it belongs in the issues list? I don't see it there. http://www.w3.org/2001/sw/WebOnt/webont-issues.html It is in the list of objectives. Effective decision procedure http://www.w3.org/TR/2002/WD-webont-req-20020307/#section-objectives Perhaps that's enough? or perhaps each objective should have a corresponding issue? -- Dan Connolly, W3C http://www.w3.org/People/Connolly/
Received on Tuesday, 23 April 2002 19:30:17 UTC