- From: Richard Waldinger <waldinger@ai.sri.com>
- Date: Fri, 31 Oct 2003 10:38:38 -0800
- To: gk@ninebynine.org, "www-rdf-logic@w3.org" <www-rdf-logic@w3.org>
Graham Klyne wrote: we have been using full first-order inference to reason about theories that combine OWL with stronger subtheories such as the natural numbers. we have done this earlier for daml+oil and are now working on a first-order axiomatization of OWL. We use SNARK as the inference engine. By going to first-order reasoning you lose decideability but gain expressive power. OWL-full is not decideable anyway, I believe. Richard > > [I originally asked this on RDF-IG, but realize this is probably the > better forum. #g] > > Does anyone have any examples of using OWL to perform > RDF-datatype-related inferencing? > > I'm thinking of datatypes, such as numbers, for which additional > properties are used to define additional relations, such as addition > over numbers. > > For example, given: > > :vehicle :seatedCapacity "30"^^xsd:integer . > :vehicle :standingCapacity "10"^^xsd:integer . > > and knowledge that the total capacity is seated capacity + standing > capacity, that one might infer: > > :vehicle :totalCapacity "40"^^xsd:integer . > > This might be expressed thus using CWM-style rules: > > { ?v :seatedCapacity ?c1 . > ?v :standingCapacity ?c2 . > (?c1 ?c2) math:sum ?c3 . } > => > { ?v :totalCapacity ?c3 . } > > It seems to me that to express such relations one must have a form of > universal quantification. But I'm not sure if anything in OWL > performs such a purpose, so I struggle to see how one might express an > idea like that above. > > Behind this question, I'm trying to see if there's a way to abstract > the rules of datatype properties away from particular application > domain. (i.e. using just RDF statements, and not rules, to express > ideas like the example above, appealing only to > application-independent rules defined on datatyped values.) Currently > I'm not seeing any way to do this, but before I give up I wanted to > see how OWL (as the major thrust for Sweb inference) deals with such > issues. > > #g > > > ------------ > Graham Klyne > For email: > http://www.ninebynine.org/#Contact >
Received on Friday, 31 October 2003 13:40:29 UTC