- From: Dan Connolly <connolly@w3.org>
- Date: Thu, 08 Nov 2001 12:51:17 -0600
- To: Pat Hayes <phayes@ai.uwf.edu>
- CC: Graham Klyne <Graham.Klyne@MIMEsweeper.com>, w3c-rdfcore-wg@w3.org
Pat Hayes wrote: >> At 05:35 PM 11/6/01 -0600, Pat Hayes wrote: >> if we then learn that _:b1 and _:b2 are equivalent, > > > ....but wait. Do we want to consider reasoning with equivalences at all? We certainly don't want to preclude it; the DAML+OIL stuff wouldn't layer on top, otherwise, would it? > That gets us into a whole lot of tar-pits which we might want to just > try to avoid, maybe (please?) [...] > So heres the rule. If we have a triple > > foo rdf:type rdf:Bag > > in a graph, then say that the nodes which are in the object position of > a triple of the form > > foo rdf:_n <object> > > in that graph are the 'foo member nodes'. No; you can't conclude from no information that there are no others. And I do think that each of the _:n properties is functional; i.e. _:x rdf:_1 "abc". _:x rdf:_1 "def". is a contradiction (is that in the model theory? subject/predicate/object are also functional). So the best I can think of is that if we have _:b rdf:type rdf:Bag. then there's some _:bc where _:b rdfs:bagContents _:bc. and where any X with _:b rdf:_NNN X. we have X rdf:type _:bc. (hmm... that might end up with a literal subject. That doesn't bother me, but if it bothers other folks, I suppose some analog of ICEXT, say IBAG is in order. Ug... this the second really serious design bug I've seen with RDF containers). > Then any graph gotten by > permuting the arcs to the foo member nodes, and replacing the node foo > by a new bnode, should be entailed by the first graph. > > Tell you want, lets agree not to talk about rdf:Bag-closures, OK? I'm not sure what a bag-closure is, but if it's the same issue as http://www.w3.org/2000/03/rdf-tracking/#rdfms-seq-representation then I don't agree not to talk about it ;-) -- Dan Connolly, W3C http://www.w3.org/People/Connolly/
Received on Thursday, 8 November 2001 13:51:21 UTC