- From: Peter F. Patel-Schneider <pfps@research.bell-labs.com>
- Date: Mon, 02 Apr 2001 13:51:10 -0400
- To: Peter.Crowther@melandra.com
- Cc: jhendler@darpa.mil, www-rdf-logic@w3.org
Some comments on how I think RDF could be changed to make it better. This is my personal opinion, so far. From: Peter Crowther <Peter.Crowther@melandra.com> Subject: RE: DAML+OIL (March 2001) released: a correction Date: Mon, 2 Apr 2001 08:37:42 +0100 > > From: Jim Hendler [mailto:jhendler@darpa.mil] > > DAML+OIL did not have authority to change anything in RDF or to > > otherwise impact the RDF spec except by example. > > Jim has (as usual) got right to the heart of the problem. Feedback between > designers of different architecture layers is essential if you want to > create a coherent architecture. So far, the sequence has been that RDF has > taken XML as a given, and DAML has taken RDF as a given --- feed-forward > with no feedback. In fact, both XML and RDF are subject to periodic > revision, but there hadn't been the time and experience of using them at the > time the initial versions were formalised (obviously!). That experience is > now starting to accrue. > > I think two interesting questions can be posed here: > > 1) How could RDF be changed/augmented/better documented to make it a firmer > base on which to build DAML+OIL? 1/ Provide a firm semantic foundation. 2/ Remove the parts that cannot be given a firm semantic foundation. 3/ Remove the insistence that everything can be represented as RDF-interpreted triples. 4/ Include facilities for datatypes. 5/ Remove the non-monotonic portions of RDFS (e.g., domain) and the non-compositional portions of RDFS where possible (e.g., range and acyclicity). > 2) How could XML be changed/augmented/better documented to make it a firmer > base on which to build RDF? 1/ Extend the use of namespaces so that they can be used throughout RDF wherever a resource name appears. 2/ Make a lightweight version of XML Schema datatypes for those who are not interested in, say, regular expression-restricted datatypes. > ... and, I guess, (3) is there any chance of these changes happening? (3), > at least, would be helped by keeping the dialogue constructive; but (1) and > (2) require constructive criticism of those existing standards in the light > of practical experience. For example, could the appropriate parts of the > Fikes & McGuinness paper be used within the next revision of RDF to provide > that clear semantics that many within DAML+OIL wish to see? I am hopeful that at least some good things will happen. There is at least some concern that under-specified standards are not a good thing. I think that the KIF axiomatization is an excellent start for an axiomatization of RDF(S). There may be other methods for providing semantics for RDF(S). I am much more partial to model-theoretic semantics. It would be useful to have several potential specifications for RDF and RDF(S). (No, I am not volunteering to provide one.) > - Peter > > [For "RDF" read "RDF and/or RDFS"; I tried to construct similar statement > for XML but was defeated by the plethora of extensions out there. X*?] Peter F. Patel-Schneider Bell Labs Research
Received on Monday, 2 April 2001 13:52:08 UTC