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RE: [UCR] RIF needs different reasoning methods

From: Gerd Wagner <wagnerg@tu-cottbus.de>
Date: Fri, 10 Mar 2006 14:50:54 +0100
To: "'Francois Bry'" <bry@ifi.lmu.de>, "'Bijan Parsia'" <bparsia@isr.umd.edu>
Cc: <public-rif-wg@w3.org>
Message-ID: <002401c64449$a6921250$55032b8d@TMGWAGNER>

Bijan Parsia wrote:
> What I don't see is the reason for specifying particular proof
> procedures *instead of* expressive subsets. 
> If two reasoners perform acceptibly and give the same answers...
> what *more* do you need? 

Ian Horrocks wrote:
> Given that a particular prover has an adequate response time and
> provides correct answers (as defined by the semantics), then why 
> would I care what procedure it uses in order to do its work? 

Bijan and Ian, you didn't get the point: rule processing is 
not just reasoning (the world is not that simple), and rule 
interchange is not just an exchange of implication formulas 
between "reasoners" (it's an old misconception of AI that 
intelligent life is all about reasoning). Most rule processing 
in real life is not involving (much) reasoning, given the fact 
that production rules and ECA/reaction rules are more important 
in IT systems than any form of derivation/deduction rules. 
Changing the state of a system and detecting complex events is
not the domain of FOL. 

Francois just tried to point out that there are these different 
types of rules, and they cannot all be processed in the same 
manner (with "reasoners"). And even for "reasoning rules",
there is a computational logic distinction between 

- rules for making definitions: constructive derivation rules, 
  called "views" in SQL
- rules for constraining the possible states (and execution
  histories) of a system: integrity rules/constraints
- rules for expressing defaults and heuristics: nonmonotonic
  derivation rules

And none of these computational logic distinctions are 
reflected in standard FOL (and neither are they in OWL/SWRL):
you can't simply combine them and submit their merge to
a "reasoner"!

Does the RIF (or the W3C) intend to ignore these distinctions?

-Gerd

---------------------------------------------
Gerd Wagner
http://oxygen.informatik.tu-cottbus.de/IT
Email: G.Wagner@tu-cottbus.de
 
Received on Friday, 10 March 2006 13:54:23 GMT

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