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Re: Expressiveness question

From: Sheila McIlraith <sam@ksl.Stanford.EDU>
Date: Sun, 28 Dec 2003 10:44:38 -0800 (PST)
To: Drew McDermott <drew.mcdermott@yale.edu>
Cc: www-rdf-rules@w3.org, <sheila@cs.toronto.edu>
Message-ID: <Pine.GSO.4.44.0312281038340.29586-100000@ksl.Stanford.EDU>


Drew,

Thanks for the response.  One of the objectives of this post was
to get a clear statement from someone developing SWRL regarding:
- what extra expressivity was required in order to encode a typical
  situation calculus axiomatization
- was it possible to extend the language.

As you note, function symbols are one necessary extension.

And to reiterate your question, is SWRL meant "to be an open-ended
framework, or a notation nailed to a rigid OWL frame?"

Comments from the SWRL-ers out there?

Sheila

On Fri, 19 Dec 2003, Drew McDermott wrote:

>
>
>    [Sheila McIlraith]
>    ...We are asking whether  we can axiomatize a situation
>    calculus [2] domain theory in SWRL.  The situation calculus
>    calculus is a first-order logical language for reasoning about
>    action and change.  It has proven sufficiently expressive for
>    axiomatizing a Web service process model, and we wondered whether
>    such a process model could be expressed in SWRL.  If not, can
>    SWRL be extended to axiomatize a situation calculus domain theory?
>
>    To this end, the following is an example of an axiom we would like
>    to encode:
>
>    Forall x. Forall s.
>      holding(x,do(a,s)) iff
>        [(a=pickup(x)) V (holding(x,s) & (a neq putdown(x))]
>
> I don't think SWRL has function terms, so it can't handle 'do',
> 'pickup', or 'putdown'.
>
> Of course, it's easy to add them.  It's not clear, I guess, whether
> SWRL is meant to be an open-ended framework, or a notation nailed to
> a rigid OWL frame.
>
> --
>                                    -- Drew McDermott
>                                       Yale Computer Science Department
>
> P.S. I'm sure William Jennings Bryan, if we were alive today, and
> still a Democrat, would endorse the "open-ended" option:  "You shall
> not crucify mankind upon a cross of OWL."
>
>
>

==============================================================================

Sheila McIlraith,
Department of Computer Science
University of Toronto
Received on Sunday, 28 December 2003 13:44:46 GMT

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