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RE: Dark triples motivation

From: Dan Connolly <connolly@w3.org>
Date: 17 Apr 2002 18:39:25 -0500
To: Pat Hayes <phayes@ai.uwf.edu>
Cc: Jeremy Carroll <jjc@hplb.hpl.hp.com>, www-webont-wg@w3.org
Message-Id: <1019086766.4818.156.camel@dirk>
On Wed, 2002-04-17 at 18:33, Pat Hayes wrote:
[...]
> >Example:
> >
> >The RDF document:
> >
> ><rdf:Description rdf:about="#John">
> >    <rdf:type rdf:resource="#Student">
> >    <rdf:type rdf:resource="#Employee">
> ></rdf:Description>
> >
> >understood with rdf:type denoting set membership, would, under almost all
> >set theories, entail #John being a member of the intersection of #Student
> >and #Employee.
> >In daml+oil this is said:
> >
> ><rdf:Description rdf:about="#John">
> >    <rdf:type>
> >     <daml:class>
> >       <daml:intersectionOf rdf:parseType="daml:collection">
> >          <daml:class rdf:ID="Employee"/>
> >          <daml:class rdf:ID="Student"/>
> >      <daml:intersectionOf>
> >     </daml:class>
> >    </rdf:type>
> ></rdf:Description>
> >
> >If we leave the daml class expression:
> >
> >
> ><rdf:RDF>
> >     <daml:class>
> >       <daml:intersectionOf rdf:parseType="daml:collection">
> >          <daml:class rdf:ID="Employee"/>
> >          <daml:class rdf:ID="Student"/>
> >      <daml:intersectionOf>
> >     </daml:class>
> ></rdf:RDF>
> >
> >as unasserted

What do you mean by that? I expected some syntactic way to tell
which triples are asserted and which aren't. I don't
see any such clues. Help?

> > then OWL can assign a meaning to this expression wholly
> >independently of RDF.

What meaning? How is the paradox avoided?

Please finish telling the story of how this solves the problem.

> >
> >
> >Have I got it?
> 
> That seems a fair summary to me, yes.

It's still not to the point where I can write test
cases to crystalize the issue.

-- 
Dan Connolly, W3C http://www.w3.org/People/Connolly/
Received on Wednesday, 17 April 2002 19:40:31 GMT

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