- From: Michael Kifer <kifer@cs.sunysb.edu>
- Date: Tue, 05 Jul 2005 11:17:17 -0400
- To: Ian Horrocks <horrocks@cs.man.ac.uk>
- Cc: www-rdf-rules@w3.org
> On 1 Jul 2005, at 23:31, Michael Kifer wrote: > > [snip] > > I guess everyone is pretty bored with this by now (I know I am), and I > think we both made our positions clear. Yes, guess we agree on this one :-) Regarding SWRL/OWL-DL, of course I know that SWRL is an extension. We are focusing on different things though. I am interested to see a use of non-trivial SWRL rules (the delta above OWL-DL), which goes beyond simple Horn. SWRL description goes beyond Horn (which is what makes this extension more complex), and I was wondering if you could point me to a realistic use case where those things are illustrated. Anyway, I agree that we have exhausted this issue (and everybody else :-) by now. --michael > One remaining point that may be worth clarifying, however... > > >> Regarding "the truly complex parts of SWRL, such as descriptions in > >> the > >> head", I'm not sure what you mean by this. The SWRL rules given in the > >> paper are used *in addition* to axioms such as the one above, and > >> capture additional property relationships that cannot be expressed in > >> OWL. In the general case, such rules lead to undecidability when > >> combined even with OWL-Lite. Is that complex enough? > > > > Ian, you are not following. The discussion was about SWRL, not OWL. > > Now I understand your confusion. The important point you have missed is > that SWRL is an extension of OWL-DL: if you look at the specification, > you will see that SWRL is OWL-DL with the *addition* of a new kind of > axiom expressing Horn clause rules. > > > I was asking if you have examples of interesting uses of the more > > advanced > > features of SWRL (not OWL) where complex rules are used. You pointed > > me to > > this paper, but the rules there are very simple. So, this didn't > > satisfy my > > curiosity. (Again, nothing against Christine's great project.) > > The interesting/advanced features involve the use of several kinds of > SWRL axiom, not just Horn clause axioms. That is what is going on here. > > I hope everything is now clear. > > Ian > > > > > > > --michael > > > > > >
Received on Tuesday, 5 July 2005 15:17:26 UTC