W3C home > Mailing lists > Public > public-owl-dev@w3.org > October to December 2008

Re: Mapping to RDF Graphs and reification

From: Bijan Parsia <bparsia@cs.man.ac.uk>
Date: Thu, 4 Dec 2008 12:44:27 +0000
Message-Id: <ECC1A06A-B623-4CBF-A674-BA8CA0700D3B@cs.man.ac.uk>
Cc: Owl Dev <public-owl-dev@w3.org>
To: Pierre-Antoine Champin <swlists-040405@champin.net>

On 4 Dec 2008, at 11:11, Pierre-Antoine Champin wrote:
[snip]
> Wouldn't
>
>  _:x rdf:type owl:NegativePropertyAssertion
>  _:x owl:sourceIndividual _:x
>  _:x owl:assertionProperty owl:sourceIndividual
>  _:x owl:targetIndividual _:x
>
> a perfect example of that paradox (in OWL Full, of course) ?

This is just syntax. You need to examine what semantic *says* that  
bit of syntax means, not just rest on intuitions. Afterall:

	ClassAssertion(Comment("This sentence is false") a C)
could be read as a similarly perfect example. But it's not according  
to the semantics since the comment is "meaningless". In a semantics  
where some comments were meaningful:

	ClassAssertion(TruthValue("FALSE") a C)

This *would* be a liar's paradox.

> What am I missing?

I'm afraid my free time and will to spelunk in the OWL Full semantics  
is minimal. So I suggest you examine:
	http://www.w3.org/2007/OWL/wiki/RDF-Based_Semantics
and try to derive the paradoxical result. If you did, we'd probably  
consider that a bug in the semantics.

(Or perhaps Michael will pop up with the interpretation.)

Cheers,
Bijan.
Received on Thursday, 4 December 2008 12:54:51 GMT

This archive was generated by hypermail 2.3.1 : Wednesday, 27 March 2013 09:32:56 GMT