Re: Web Rule Language - WRL vs SWRL

This is quite an interesting thread though I also suggest that people take a 
look at the interesting work that the REWERSE guys are doing in relation to 
SW rule languages.

http://www.rewerse.net

Regards

Charlie

On 6/23/05, Bijan Parsia <bparsia@isr.umd.edu> wrote:
> 
> 
> On Jun 23, 2005, at 3:06 AM, Jos de Bruijn wrote:
> 
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> > Bijan Parsia wrote:
> [snip]
> >> Key is the slipping in of "ground".
> >
> > No. For query answering only ground entailment is relevant.\
> 
> Interesting presumption.
> 
> >>> entailments for both
> >>> semantics are *equivalent* and thus the queries would return the same
> >>> result.
> >>
> >>
> >> Of course, RDF entailment includes existential generalization, so
> >> that's not quite right. There seems to be more work that you need to
> >> do to get what you wanted (e.g., you need to look at the semantics
> >> of the query language; is the query "not" classical? how would that
> >> classical not interact with the LP semantics?)
> >
> > The RDF language contains existentials and I'm not claiming that this
> > can be done by a rule language.
> > We are talking about Horn Logic and Horn Logic does not have
> > existentials! I never claimed this!
> > You claimed
> 
> Please point to where I claimed this.
> 
> > that a Horn formula under FOL semantics has other ground
> > entailments than a Horn formula under LP semantics and this is simply
> > not true.
> > I think this can conclude our discussion on this topic.
> [snip]
> Oh, I *quite* agree. But perhaps not for the same reasons.
> 
> Cheers,
> Bijan.
> 
> 
>