Re: Expressiveness question

   [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."