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Re: Fwd: Re[2]: OWL CR feedback: owl:Class 'vs' rdfs:Class causing pain. Is owl:Class really needed?

From: Jeremy Carroll <jjc@hplb.hpl.hp.com>
Date: Thu, 18 Sep 2003 16:16:54 +0200
Message-ID: <3F69BE56.4080508@hpl.hp.com>
To: www-webont-wg@w3.org


Looking at Pat's msg

http://lists.w3.org/Archives/Public/public-webont-comments/2003Sep/0010.html


I see that he is distinctly misleading, and wonder if we should add a 
test case (to contradict him).

DanBri:
 >>Are all RDF classes OWL classes?
Pat:
 >No. RDFS has a more general notion of class than OWL has. In
 >particular, rdfs:Class is not an OWL class.

Within OWL Full the statement above is false.

Hence we should have an OWL for OWL test - i.e. a trivially true 
document, that shows:

rdfs:Class owl:equivalentClass owl:Class .

That's what it says in S&AS section 5.

We should perhaps spell that out with

rdfs:Class rdf:type owl:Class .

The rationale as I understand it, is that the semantic layering ended up 
worse than we expected, and within our proofs, we needed the two 
concepts owl:Class and rdfs:Class to be distinct - this does not say 
that it is needed to be like this, merely that that was the best we 
could do.

I should dig out the response we sent to RDF Core last time round.

Jeremy
Received on Thursday, 18 September 2003 10:42:56 GMT

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