W3C home > Mailing lists > Public > public-rule-workshop-discuss@w3.org > August 2005

Re: Comments on * DRAFT * Rules Working Group Charter $Revision: 1.60 $

From: Michael Kifer <kifer@cs.sunysb.edu>
Date: Wed, 24 Aug 2005 12:50:08 -0400
To: Jim Hendler <hendler@cs.umd.edu>
Cc: Dieter Fensel <dieter.fensel@deri.org>, public-rule-workshop-discuss@w3.org
Message-Id: <20050824165009.B329F19E75F@kiferdesk.lmc.cs.sunysb.edu>


Jim Hendler wrote:
> 
> Dieter wrote:
> 
> 
> >On the other hand, it is not that difficult to identify something 
> >around Horn logic
> >with a minimal model as common ground of state of the art rule languages.
> 
> 
> Mike wrote:
> 
> >The only rule language that FOL is a superset of (modulo a mapping) is SWRL
> >- an untested newcomer. And of Horn Datalog, which is near-useless. All the
> >real rule-based languages don't map into FOL AFAIK.
> 
> Am I the only one confused?  Why is "Horn logic with a minimal model" 
> so preferable to "Horn Datalog"?

Jim,

I didn't write about the minimal models. I was trying to stick to the
precise definition of "Horn", which doesn't include negative queries.
So, in this case, minimal models are not needed. Dieter probably had
negative queries in mind.

But, as I wrote before, pure Horn is near-useless, so in the end we need
negative body literals, minimal models, etc.


	--michael  
Received on Wednesday, 24 August 2005 16:50:17 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Tuesday, 8 January 2008 14:16:23 GMT