- From: <Patrick.Stickler@nokia.com>
- Date: Wed, 14 Nov 2001 21:08:29 +0200
- To: Graham.Klyne@MIMEsweeper.com
- Cc: danbri@w3.org, phayes@ai.uwf.edu, w3c-rdfcore-wg@w3.org
Thanks. That does clarify things for me. Patrick > -----Original Message----- > From: ext Graham Klyne [mailto:Graham.Klyne@MIMEsweeper.com] > Sent: 14 November, 2001 19:34 > To: Stickler Patrick (NRC/Tampere) > Cc: danbri@w3.org; phayes@ai.uwf.edu; w3c-rdfcore-wg@w3.org > Subject: RE: ACTION 2001-11-02#02: Datatyping use-cases from CC/PP > > > At 03:29 PM 11/14/01 +0200, Patrick.Stickler@nokia.com wrote: > >No. But I'd hope that we *are* the right WG to define RDF Schema to > >say things like 'an instance of the person class must have two > >and only two values for the property x:parent and the values of > >those properties may not be identitical (share the same URI). > > Not, as far as I am aware: the DAML+OIL and Web ontology groups are > building those structures on top of RDF. > > >Right? Otherwise, we are left with *no* means whatsoever to > >define constraints about manditory knowledge for specific > >applications. XML Schema cannot define constraints for knowledge > >bases build from the syndication of multiple instances, so > >the constraint functionality offered by RDFS is critical. > > Yes: no such means within core RDF(S). > > >Am I really understanding you correctly as saying that RDFS > >no longer defines any constraints whatsoever? > > That's my understanding. > > >Where then does the responsibility get shifted to? DAML+OIL? > >The WebOnt WG deliverables? > > That's my expectation. > > .. > > You (and others) might argue that this means RDF(S) is only "half a > solution". For some purposes, that may be true, but I > strongly believe > that for many other applications it is enough. The availability of a > simple, consistent language for applications to express > ground facts is a > very powerful tool. Its's simplicity (from a developer > perspective) will > be, in my view, a key factor in getting lots of raw metadata > out there on > the web for more advanced reasoning engines to chew upon and > generally work > their magic. The logical consistency of this simple language > is crucial to > ensuring that more powerful generic layers (DAML_OIL, WebOnt > and more) can > be built on this foundation. > > Here are some notes I used to present RDF to our development team: > http://public.research.mimesweeper.com/RDF/RDFMetadataForEndTo EndContent.html #g ------------------------------------------------------------ Graham Klyne MIMEsweeper Group Strategic Research <http://www.mimesweeper.com> <Graham.Klyne@MIMEsweeper.com> __ /\ \ / \ \ / /\ \ \ / / /\ \ \ / / /__\_\ \ / / /________\ \/___________/
Received on Wednesday, 14 November 2001 14:08:25 UTC