- From: Jeremy Carroll <jjc@hpl.hp.com>
- Date: Fri, 06 Sep 2002 15:08:04 +0200
- To: Ian Horrocks <horrocks@cs.man.ac.uk>
- Cc: www-webont-wg@w3.org
> Given a sufficiently expressive language (i.e., one like OWL), this
> doesn't represent any restriction w.r.t. what you ask for below, i.e.,
> being able to determine if ontology O1 models ontology O2. This is
> trivially reducible to ontology consistency.
IIUC only if you can negate an Ontology.
not(prop rdf:type owl:TransitiveProperty )
is not in OWL.
> Similarly
> for a DL, the frame axioms might state that there is a subset of the
> set of all property names (the transitive properties) whose
> interpretations must be transitively closed.
In terms of Pat's document then
If E is:
owl:TransitiveProperty
then x is in ICEXT(I(E)) iff:
<y, z> and <z, u> in IEXT(x) implies <y, u> in IEXT(x)
should be weakened to
If E is:
owl:TransitiveProperty
then [[ x is in ICEXT(I(E)) implies
{ <y, z> and <z, u> in IEXT(x) implies <y, u> in IEXT(x) }
]]
I still haven't understood which way you prefer to go on this.
Sorry. (I found your message quite difficult :( ).
e.g.
>Having said that, the expressive power of OWL means that entailment
>w.r.t. ontologies containing property inclusion and transitivity
>axioms is still trivially reducible to ontology consistency.
Could you please give an example:
e.g.
{ empty }
does not entail
{ foo rdf:type owl:TransitiveProperty }
how do I convert that into a consistency question?
Jeremy
Received on Friday, 6 September 2002 09:08:22 UTC