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Re: ACTION-280 completed

From: Ivan Herman <ivan@w3.org>
Date: Thu, 05 Feb 2009 14:28:22 +0100
Message-ID: <498AE976.4050404@w3.org>
To: Bijan Parsia <bparsia@cs.man.ac.uk>
CC: public-owl-wg Working Group <public-owl-wg@w3.org>
Hi Bijan,

Somewhere down the lines you say:

Accordingly, the working group has decided not to make the change you've

My feeling of yesterday's meeting was that we did not really understood
what Frank is saying (although it is 90% sure that he really
misunderstood). Didn't we say that we would ask him whether this
explanation is an answer to his issue or whether he was thinking of
something else?

Just my 2 cents... (sorry, 2 pence, you are in the UK and 2 pence still
has a _slightly_ higher value than 2 cents:-)


Bijan Parsia wrote:
> I tweaked it just a little bit.
> Cheers,
> Bijan.
> To: Frank van Harmelen <Frank.van.Harmelen@cs.vu.nl>
> CC: public-owl-comments@w3.org
> Subject: [LC response] To Frank van Harmelen
> Dear Frank,
> Thank you for your comment
> <http://lists.w3.org/Archives/Public/public-owl-comments/2009Jan/0037.html>
> on the OWL 2 Web Ontology Language last call drafts.
> First, we'd like to note that the shift in the specification from using
> truly blank nodes to using nodeIDs is not a change to the *language* but
> merely a change in the *presentation* of the language. No new
> capability, esp. from the RDF perspective, has occurred. In the old
> specification:
>     <http://www.w3.org/TR/owl-semantics/>
> the patterns of admissible blank nodes (roughly, tree like patterns that
> can be mapped to nested someValuesOf) could be specified without
> recourse to nodeIDs due to the (tree-like) frame structure of Abstract
> syntax constructions. Unfortunately, this is not possible in the new
> functional syntax, hence we must make use of a different mechanism to
> express the same point. Additionally, we believe there is value in
> having explicit nodeIDs, borrowing from RDF, since it makes it clear
> that there is an actual, significant syntax item there.
> Here is an example of the difficulty:
> (Remember, in <http://www.w3.org/TR/owl-semantics/syntax.html#2.2>:
>    """The syntax here is set up to somewhat mirror RDF/XML syntax [RDF
> Syntax] without the use of rdf:nodeID.""")
>   Individual(anObjectProperty
>                 Individual(aDataProperty "foo"))
>   [anObjectProperty
>          [aDataProperty "foo"]]
>    _:x anObjectProperty _:y.
>    _:y aDataProperty "foo".
>   PropertyAssertion(anObjectProperty _:x _:y)
>   PropertyAssertion(aDataProperty _:y "Foo")
> This is essentially an issue of surface syntax used in the
> specification. The FS is designed such that axioms in the FS correspond
> to axioms in first order logic (which makes various specification issues
> easier). This makes it impossible to use implicit BNodes. Furthermore,
> given the tradition of using nodeIDs in RDF, we feel we are well within
> best practice and, in fact, think that this style makes what's going on
> substantively clearer.
> Accordingly, the working group has decided not to make the change you've
> suggested.
> Please acknowledge receipt of this email to
> <mailto:public-owl-comments@w3.org> (replying to this email should
> suffice). In your acknowledgment please let us know whether or not you
> are satisfied with the working group's response to your comment.
> Regards,
> Bijan Parsia
> on behalf of the W3C OWL Working Group


Ivan Herman, W3C Semantic Web Activity Lead
Home: http://www.w3.org/People/Ivan/
mobile: +31-641044153
PGP Key: http://www.ivan-herman.net/pgpkey.html
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Received on Thursday, 5 February 2009 13:28:59 UTC

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