- From: Dan Connolly <connolly@w3.org>
- Date: 19 Sep 2002 10:37:10 -0500
- To: Pat Hayes <phayes@ai.uwf.edu>
- Cc: www-webont-wg@w3.org
On Wed, 2002-09-18 at 19:51, pat hayes wrote: > > Heres a non-technical summary of the basic idea of how to resolve > issue 5.3 along the lines currently being worked out. I am sending > this now in case the issue comes up at the telecon. [...] Until I see a design document that meets all these promises, I'm still a little skeptical. But I like the direction here. In particular: > 2. The 'weak' meanings of the OWL vocabulary can be given without > making any assumptions about the relationship between the OWL > universe and the RDFS universe. These meanings correspond roughly to > the DAML-style semantics that Peter refers to in issue 5.10, ie they > do not incorporate any assumptions about the existence of classes > that are not explicitly named. So they do not support many of the > 'intuitive' entailments that Peter has pointed out. (Though see 7. > below.) and > 4. If one makes additional assumptions about the OWL universe, so > that its various parts are disjoint in the ways described in the OWL > MT, and that this restricted universe is closed under the various > class constructors (such as union/intersection and restrictions) then > one gets the 'strong' meanings of full OWL, but on a more restricted > universe. This supports a lot more entailments and also allows > efficient DL reasoners to work properly, providing a computational > guarantee of inferential power, but only on a suitably restricted > ('layered') use of the OWL vocabulary. Still, many users may be happy > to stay inside the restrictions in order to gain the extra utility. Oh... and as to... > Write-up coming soon (Friday). Here's hoping! -- Dan Connolly, W3C http://www.w3.org/People/Connolly/
Received on Thursday, 19 September 2002 11:38:05 UTC