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Re: Properties no longer required to be resources?

From: Brian McBride <bwm@hplb.hpl.hp.com>
Date: 31 Jul 2003 10:45:42 +0100
To: pat hayes <phayes@ihmc.us>
Cc: rdf core <w3c-rdfcore-wg@w3.org>
Message-Id: <1059644742.2343.26.camel@dhcp-91-3.hpl.hp.com>

On Wed, 2003-07-30 at 20:18, pat hayes wrote:
> >I just noticed an editorial (?) tweak (pointed out by pfps) to the
> >semantics document that the semantic constraint that properties must be
> >a subset of resources has been removed from the current editors draft.
> >
> >http://www.w3.org/2001/sw/RDFCore/TR/WD-rdf-mt-20030117/#interp
> >
> >Pat, this is rather more than just an editorial tweak.
> 
> This is only for simple interpretations. It does not make any 
> difference to RDF or RDFS interpretations, since those 
> interpretations are still required to conform to the subset condition 
> by virtue of their semantic conditions; cf. section 3, 5th para 
> (after the table of RDF semantic conditions):

This assertion comes as a considerable relief to me.  I confess I did
not read the text of that paragraph, I just looked at the math and it
was not obvious to me that IP must be a subset of IR.

I then checked the now complete (?) closure rules in 7.2 and couldn't
see how to get the required entailment.  The required entailment seems
to require rule RDFS4a - thus its an RDFS entailment, not an RDF
entailment.

I know better than to argue mathematics with you, but maybe you could
reassure me by spelling out what I'm missing.

[...]

> 
> If you really feel that this is a serious matter then I can go back 
> and undo this, but I would rather not, as this makes it clearer that 
> it is RDF itself which imposes this condition on IP (by virtue of the 
> 'type Property' condition on properties) rather than the graph syntax 
> in some mysterious way.

I don't want you to have to change anything.  Please just talk me out of
my concerns.

Brian
Received on Thursday, 31 July 2003 05:49:39 EDT

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