- From: pat hayes <phayes@ai.uwf.edu>
- Date: Tue, 27 May 2003 16:19:22 -0500
- To: Brian McBride <bwm@hplb.hpl.hp.com>
- Cc: w3c-rdfcore-wg@w3.org
>Danbri and I have been discussing issue: > > http://www.w3.org/2001/sw/RDFCore/20030123-issues/#vass-01 > >Its quite hard to get a crisp quote of the problem from the email >thread but I think the issue is that schema does not layer the same >way as, say UML, in that classes can be members of themselves and >one can take a subproperty of subPropertyOf or rdf:type. > >I think we need to clearly articulate the advantages of the design >choice that has been made. I disagree. first, we did not make it, it was imposed by our charter. Second, the only objection to it from this comment can be succinctly phrased as "I don't like that way of doing it" which does't really need to be dignified with a careful answer, particularly in view of the fact that when asked for clarification, the commentor's response was somewhere between unhelpful and downright rude. > >I suggest the following reason for the design choice and why we >should not change. I welcome comments and other suggestions: > >1) RDFS is designed to be a lower layer for the semantic web stack >that is extended by restriction. All structure at this layer is >imposed on all higher layers. A layered structure is not necessary >and the principle of minimal restriction suggests it should be >omitted. > >2) A further consideration is the cost of change at this point. To >switch to a layered approach would require a massive rethink and >would affect not only the RDFCore specs but also OWL. Only a show >stopping problem with the current design could justify the cost of >such a change. > >We note that it is possible to build more strictly layered languages >on top of RDF(S), Owl DL/Lite being examples. That might be well worth articulating in more detail. I think we could do a fairly exact job on this which a lot of people would find helpful. Since Jeremy has already done the donkey work for this in defining how to tell if an OWL-RDf graph is in OWL-DL ( which is precisely the 'layered' subset of OWL in this sense), we should be able to easily adapt his algorithm to define a 'layered style' of writing RDF and put it in an appendix somewhere. I am willing to tackle writing a draft of this. It would be relevant to vass-01, pan-01 and Qu-03. Pat -- --------------------------------------------------------------------- IHMC (850)434 8903 or (650)494 3973 home 40 South Alcaniz St. (850)202 4416 office Pensacola (850)202 4440 fax FL 32501 (850)291 0667 cell phayes@ai.uwf.edu http://www.coginst.uwf.edu/~phayes s.pam@ai.uwf.edu for spam
Received on Tuesday, 27 May 2003 17:19:53 UTC