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Re: was Converting SHOE to RDF, now data models

From: Ken Laskey <kenneth.j.laskey@saic.com>
Date: Wed, 24 May 2000 13:23:48 -0400
Message-Id: <p04310105b551bf97edd1@[10.43.242.28]>
To: guha@guha.com, Graham Klyne <GK@Dial.pipex.com>
Cc: Dan Connolly <connolly@w3.org>, www-rdf-interest@w3.org
As presently conceived, can a data model which is equivalent to and 
can extend beyond the present RDF data model be built using XML 
Schema?  Is there something in the RDF model that provides extra 
value or can support extensions that cannot be done under XML Schema?

Ken

At 7:49 AM -0700 5/23/2000, Guha wrote:
>A "logic language" requires a "model theory". A model
>theory usually specifies how a set of statements made
>in the language can be interpreted as a set of satisfying
>structures. This specifies semantic implication (|=). It
>can then optionally have a "proof theory", which specifies
>how to (mechanically) go about deducing statements
>in the language (|-).
>
>RDF makes an initial stab at a model theory by virtue
>of its data model. If we clean it up and finish it, we will
>have a simple and rudimentary model theory for RDF.
>But as it stands now, we don't really have a logical language ...
>
>Of course, I am just clinging on to old-fashioned definitions ...
>
>Guha
>
>Graham Klyne wrote:
>
>>  At 12:26 AM 5/14/00 -0500, Dan Connolly wrote:
>>  >Hmm... I'm not sure what you mean by "full semantic understanding."
>>  >RDF has no built-in logic whatsoever. The "full semantic understanding"
>>  >depends on more than just the availability of various things...
>>  >it depends on what inference rules you choose to use, what
>>  >sort of logic, etc.
>>
>>  A question, if I may...
>>
>>  I have seen two kinds of statement made about logic in RDF:
>>
>>  (a) RDF has logical conjunction (multiple predicates of a subject generally
>>  taken to be parts of a conjunction)
>>
>>  (b) RDF has no built-in logic (as you say above)
>>
>>  Are there differing views, or am I missing something?
>>
>>  #g
>>
>>  ------------
>>  Graham Klyne
>>  (GK@ACM.ORG)

-- 

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* Ken Laskey                                                   *
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Received on Wednesday, 24 May 2000 13:22:44 GMT

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