W3C home > Mailing lists > Public > www-rdf-rules@w3.org > June 2005

Re: Web Rule Language - WRL vs SWRL

From: Michael Kifer <kifer@cs.sunysb.edu>
Date: Thu, 30 Jun 2005 01:35:21 -0400
To: Ian Horrocks <horrocks@cs.man.ac.uk>
Cc: Jos de Bruijn <jos.debruijn@deri.org>, Holger Wache <holger@cs.vu.nl>, Jim Hendler <hendler@cs.umd.edu>, dreer@fh-furtwangen.de, www-rdf-rules@w3.org, public-sws-ig@w3.org, Bijan Parsia <bparsia@isr.umd.edu>
Message-Id: <20050630053521.93813CB5D3@kiferserv.kiferhome.com>


> So it is inappropriate to show LP and FO language towers  
> interoperating via a common DLP base - they would sink in and topple  
> over.

Ian,
We are going back and forth on this. I suppose that this is so because you
were traveling and didn't read all the messages. Let me summarize briefly

1. I am not aware of anyone (among the people who proposed the 2-stacks on
   top of DLP) claiming that the two stacks *interoperate* through DLP.

   I believe that this is your own extrapolation from nothing more than
   just the appearance of the diagram (and maybe some vaguely remembered
   accompanying words--certainly not my words).

2. The claim is that both stacks extend DLP *as languages* -- semantically
   and syntactically (the latter after some mapping, of course).
   We use the standard definition of language extension here (which I
   have spelled out in a previous message).

3. The interoperability part is only alluded to in the diagram under the name
   "logical framework". (I wonder who proposed he term "logical framework"
   -- this term is much better than what we had in the original diagram.)

   The interoperability framework uses the black box architecture similar
   to AL-Log, Eiter et al., etc.


> > People think databases but use OWL.
> > Now, this is a real semantic mismatch: people mean (and want!) one  
> > thing,
> > but get a completely different thing.
> 
> You need to get out more. I meet and interact with many users who are  
> building large and complex ontologies, and who have a very good grasp  
> of the semantics of OWL. Hopefully you caught the presentation from  
> Christine Golbreich at the rules workshop and have been keeping up with  
> the work being done in the SWBP working group. You should also look at  
> what is being done by NCI, SNOMED and the Gene Ontology Consortium  
> amongst many others.

Thanks for the advise.  I am trying to get out whenever I can. And you
should also try to visit places outside of your immediate neighborhood.

I am not involved in any of the aforesaid great projects, but occasionally
I do run into interesting articles
    http://ontology.buffalo.edu/medo/NCIT.pdf
    http://www.ipsi.fraunhofer.de/orion/pubFulltexts/NCIReview18Feb04.pdf
which raise questions about the use of OWL for NCIT.

> > Second, DLP is not the only interoperability option. A more general  
> > one (and the one that I happen to like) treats the different languages
> > as black boxes, which can be queries according to the native semantics
> > of those boxes.
> > I was actually surprised that you referenced Eiter et al. paper, because in
> > my view they argue in favor of the 2-stack architecture with a defined
> > interoperability layer based on the black box idea.
> 
> Now we are getting somewhere! Developing a framework that allows for  
> multiple language types to co-exist in the semantic web while  
> maximising interoperability is exactly what myself (and others) have  
> been arguing for! I believe that the Eiter work, as well as other work  
> by Motik, Rosati, Franconi, and others, provides a promising basis for  
> such a framework, but that some of the details still need to be worked  
> out.


Nice that we appear to agree on something.


> > SWRL is complex in a wrong way. How many people use it in a way
> > where programs come out substantially non-Datalog? (I.e., where one  
> > can't accomplish the same thing in an LP-style language in a simpler way?)
> 
> See my comment above - more than are drempt of in your philosophy.

We are talking about SWRL here, not OWL, are we?
Can you please point me to the use of SWRL in NCI, SNOMED, etc., which
requires the complexity of SWRL? (Something that goes beyond, say, the
simple AL-Log?)


	--michael  
Received on Thursday, 30 June 2005 05:35:44 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:53:12 GMT