Re: OWL equivalentClass question

On Fri, Jul 13, 2012 at 1:47 PM, David Booth <david@dbooth.org> wrote:

> On Fri, 2012-07-13 at 13:08 -0400, Alan Ruttenberg wrote:But that would
> render skolemization impossible, and it would conflict
> with the treatment of blank nodes as existentially qualified variables
> http://www.w3.org/TR/rdf-mt/#unlabel
> since it would be like saying "there exists an x, but you're not allowed
> to name x with a URI".
> >
>

It would be like saying, you can't change an expression "there exists an x"
to "x". They don't mean the same thing. If you have "y" then it implies
there exists an x. But it doesn't imply "x". Blank nodes, according to the
RDF semantics, mean "there exists an x".

As such, it would seem to break RDF entailment.

And if this is correct I would expect there to be a formal objection to the
proposal.

Perhaps Micheal could shed some light.

-Alan


>
> --
> David Booth, Ph.D.
> http://dbooth.org/
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