- From: Leo Obrst <lobrst@mitre.org>
- Date: Tue, 11 Dec 2001 18:14:42 -0500
- To: Jim Hendler <hendler@cs.umd.edu>
- CC: Tim Finin <finin@cs.umbc.edu>, "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>, www-webont-wg@w3.org
If rules are outside our charter, what about statements of equivalences between 2 ontologies (e.g., for semantic mappings for the content interoperability use case)? I believe DAML+OIL just has daml:sameClassAs (class expressions) daml:equivalentTo (class or property expressions) [and when applied to properties, is the same as samePropertyAs] daml:samePropertyAs (property expressions) Is this sufficient? I think these are ontology-internal constructs, no? Might they be used across ontologies? I also note that there is no meta level to DAML+OIL and I think that was a conscious choice, no?, though I don't know the history of that decision. Sometimes having a modifiable meta level is a very good thing (future language extensions, e.g.) Leo Jim Hendler wrote: > > At 12:39 PM -0500 12/11/01, Tim Finin wrote: > >"Peter F. Patel-Schneider" wrote: > >> I am concerned that the group is not working on the ontology language > >> itself. There are a number of changes that need to be done to DAML+OIL, > >> largely because of changes that have happened since DAML+OIL was designed. > >> ... > > > >Are adding capabilities to the language, such as the ability > >to express rules, on our radar screen? Some of the use cases > >that I am interested (e.g., representing security policies) > >will eventually require encoding some rules. > > rules are explicitely out of our charter. There is a forum > (www-rdf-rules) for discussing rules and query, and the feeling in > W3C leadership was that consensus on the "structural" part of the > ontology (my word - by it I mean the class/subclass/property part of > the world) was much stronger than in the rules world. It is expected > that if rules/query stuff reaches a consensus informally, they will > come to W3C with a request for their own WG. One might or might not > agree as to whether this was the right way to do things, but the > charter lists the following things as out of bounds, and on this our > hands are tied > -JH > p.s. Note to web service use case group -- the last one of these also > applies in some sense to Web services - we are not trying to come up > with primitives for web services or any specific web-service related > content. Showing how webont enhances ability to do things with web > services, however, is clearly within our charter to develop use cases > and requirements. > > > * Query Rules and query langauges A serious rule language that > >can be used for complex inferencing, exchange of proofs, and/or the > >querying of RDF or Web Ontology documents or repositories is > >desirable to the eventual development of the semantic web, but out > >of the scope of the current working group. However, this effort will > >coordinate with any rule or query working groups that may be > >constituted as part of the semantic web effort. > > * Universal Web Logics Much discussion on www-rdf-logic@w3.org > >has focused on a universal web logic (UWL) -- the possibility of > >creating a usable logic that can express any possible web content. > >There is discussion as to whether this is feasible (or even > >possible) and as to what features this language might have. The goal > >of this working group is explicitly not to define such a universal > >system, but rather a more limited system of immediate use to the web > >community. The current product may indeed provide a lower layer on > >which an eventual UWL can be built, but given the expressibility vs. > >use trade-offs mentioned above, is not expected to be able to > >directly result in such a logic. > > * Agent Communication Languages One use of web ontologies and > >logics is in support of agent-based computing. While the working > >group will provide products of use to such systems, the explicit > >design of agent infrastructure is not a working group goal. In > >particular, a number of Agent Communication Languages have been > >proposed, and sets of appropriate performatives discussed at great > >length. Such work is important to the world at large, but out of the > >scope of this working group. > > > -- > Prof. James Hendler Director, Semantic Web and > Agent Technology > 301-405-2696 (phone) Maryland Information and Network Dynamics Lab > 301-405-8488 (fax) University of Maryland > http://www.cs.umd.edu/~hendler College Park, MD 20742 -- _____________________________________________ Dr. Leo Obrst The MITRE Corporation mailto:lobrst@mitre.org Intelligent Information Management/Exploitation Voice: 703-883-6770 7515 Colshire Drive, M/S W640 Fax: 703-883-1379 McLean, VA 22102-7508, USA
Received on Tuesday, 11 December 2001 18:16:47 UTC