- From: Michael Kifer <kifer@cs.sunysb.edu>
- Date: Fri, 26 Aug 2005 17:08:45 -0400
- To: Sandro Hawke <sandro@w3.org>
- Cc: jos.deroo@agfa.com, Christian de Sainte Marie <csma@ilog.fr>, dieter.fensel@deri.org, public-rule-workshop-discuss@w3.org
> Michael Kifer writes:
> > Merging rules is a whole different ball of hair. As far as I
> > can tell, logical reasoning (monotonic or nonmonotonic) is not what you
> > would use here. This is an intellectual activity, which can be automated
> > with the help of heuristics (which are not logical inference rules),
> > machine learning, etc.
> >
> > I bet, however, that **if** you decide to encode those rule-merging
> > heuristics in a rule-based language (and not in Java, for instance) then
> > you would prefer a Prolog-like language with S/NAF rather than FOL.
>
> The Semantic Web applications I'm familiar with (including everything
> based on cwm, some of my prolog work, and various things I hear about)
> all merge rulesets freely by just puting them together (concatenation,
> set-union, conjunction, etc). It's trivial with RDF, OWL, N3, and FOL
> (when you use URIs for names). It sounds like it might be very hard
> or impossible with rules written in a non-monotonic language.
1. N3, as I hope we have established by now, is nonmonotonic.
2. Merging rules by concatenation is trivial in Prolog and languages like
Flora-2, which allow for rule reification.
When I mentioned heuristics for merging rules I was talking about more
interesting issues. You can view schema merging as a special case of rule
merging. You wouldn't do this by just unioning schemas.
> Is this the root of all the tension around NAF/LP/etc?
Root of tension? I don't see any tension. The issue is understanding what
paradigm suits what tasks, and I don't see this understanding among some of
the proponents of FOL, cwm, N3, etc.
--michael
Received on Friday, 26 August 2005 21:08:57 UTC