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Re: NAF v. SNAF - where is this being addressed?

From: Dave Reynolds <der@hplb.hpl.hp.com>
Date: Wed, 06 Jul 2005 09:19:20 +0100
Message-ID: <42CB9408.4000801@hplb.hpl.hp.com>
To: Gerd Wagner <wagnerg@tu-cottbus.de>
Cc: public-rule-workshop-discuss@w3.org

>>I think the point is that RDFS and OWL are designed to be 
>>monotonic 
> 
> 
> Monotonicity should not be a primary W3C design goal.
> It's a nice property for nice and clean mathematical 
> theories, since mathematics deals with eternal truths
> and with cumulative knowledge.

Sorry if I wasn't clear. I was using "monotonic" in the rather limited 
sense of monotonic reasoning rather than the sense that facts on the 
semantic web are/should be eternal and unchangeable.

Given a set of assertions and axioms an OWL reasoner will only make 
deductions which would remain true if further such assertions were 
added. This seems to be a useful feature given the fundamental open 
world assumption behind the semantic web.

It's not saying that RDF and OWL data is immutable and can never be 
changed. Clearly that's necessary and entirely reasonable, and clearly 
any changes to data that a reasoner sees will change (non-monotonically) 
the deductions it can make.

> And again: the important point about a Web-oriented use
> of NAF is not really "scope" (in the sense of provenance)
> but its relationship to definitive knowledge (as captured
> by N3's "definitiveDocument" construct).

I think the term "scope" is intended to convey things just like the 
definitiveDocument construct.

Dave
Received on Wednesday, 6 July 2005 08:19:42 GMT

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