- From: Jos De_Roo <jos.deroo.jd@belgium.agfa.com>
- Date: Tue, 6 Aug 2002 17:42:54 +0200
- To: "Christopher Welty" <welty@us.ibm.com>
- Cc: Ian Horrocks <horrocks@cs.man.ac.uk>, www-webont-wg@w3.org
Chris, > Jos, > > I believe it's fairly safe to say "it may be impossible." That is not a > claim that it IS impossible, it is merely a claim that those of us who > BELIEVE it is impossible await an existence proof from those who don't. fair enough (just read his words as "... that it *is* ... impossible ...") > If you want to make Ian change his language, I suggest you offer a proof. > Even an idea of how it might be done would be a start. right I'm trying working out one using Euler in --think mode and somehow along the lines of the proof of all proofs of ?s ?p ?o given an owl-theory.n3 should be a fixed-point my motivation is that machines can help us a lot in these that we can have no comprehension axioms (maybe) but I'm not yet there ;-) -Jos > -Chris > > Dr. Christopher A. Welty, Knowledge Structures Group > IBM Watson Research Center, 19 Skyline Dr. > Hawthorne, NY 10532 USA > Voice: +1 914.784.7055, IBM T/L: 863.7055 > Fax: +1 914.784.6078, Email: welty@us.ibm.com > > > > > > "Jos De_Roo" <jos.deroo.jd@belgium.agfa.com> > Sent by: www-webont-wg-request@w3.org > 08/05/2002 08:02 PM > > > To: Ian Horrocks <horrocks@cs.man.ac.uk> > cc: www-webont-wg@w3.org > Subject: Re: OWL semantics > > > > > [only a very partial reply] > > [...] > > > It is also worth pointing out that such axiomatisations are invariably > > large and complex, and that it is difficult/impossible to be sure that > > they are correct. E.g., take a look at the axiomatisation of > > DAML+OIL/RDF in [3], which contains around 140 axioms. FOL reasoners > > can be used to detect "obvious" inconsistencies (as happened with > > earlier versions of [3]), but simply ironing these out is a LONG way > > from proving that the axiomatisation correctly captures the meaning of > > the language. > > that is not enough to suggest a > "impossible to be sure that they are correct" > let's just call it difficult/challenging > engineering and no more > > -- , > Jos De Roo, AGFA http://www.agfa.com/w3c/jdroo/ -- , Jos De Roo, AGFA http://www.agfa.com/w3c/jdroo/
Received on Tuesday, 6 August 2002 11:43:32 UTC