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Re: reference needed

From: Lynn Andrea Stein <las@olin.edu>
Date: Wed, 4 Jun 2003 17:15:55 -0400
Cc: www-rdf-logic <www-rdf-logic@w3.org>
To: Sandro Hawke <sandro@w3.org>
Message-Id: <BABA04B6-96D1-11D7-8BDF-0003935484F2@olin.edu>

> Resent-From: www-rdf-logic@w3.org
> From: Sandro Hawke <sandro@w3.org>
> Date: Wed Jun 4, 2003  3:12:53  PM US/Eastern
> To: www-rdf-logic <www-rdf-logic@w3.org>
> Subject: Re: reference needed
>
>> but what if we're using
>> an inferencing engine to reason about RDF statements? Would the engine
>> treat all occurrences of SlashURIs as referring to the thing itself,
>
> All URIs in RDF refer to things themselves.  Those things themselves
> might be web pages.


But the URI (e.g., http://www.w3.org/Consortium/) construed in RDF (or 
RDFS or OWL)  can't simultaneously refer to

1) the bits returned by http get on that particular page
AND
2) whatever happens to be the current description of the W3C

let alone

3) the Consortium itself

etc.

In particular, if the bits returned are different tomorrow, 
interpretation (1) says either the URI still refers to the old bits OR 
the reference relation has changed -- the URI maps onto a different 
thing tomorrow -- while (2) says that the reference relation has 
remained the same while the referenced object has (internally) changed 
(its representation).

So, while I agree completely that

>
> I think the RDF Model Theory is very clear that URIs (aka URIRefs)
> function in RDF just like constant symbols in classical logic.  No
> dereferencing is involved in knowing that each URI acts (within an
> interpretation) as a name for something in the domain of discourse.
>

I've never been quite clear on which the (some)thing(in the domain of 
discourse) is that the URIRef names.  I suppose that I can use it 
however I want, but only at the risk of diluting the U -- universality 
-- in the URI.  And of course all three of (1) the bits returned (2) 
the (changing) current description and (3) the Consortium are things 
and so properly nameable by URIs....the question is just *which* URI 
(or *which* thing).
Received on Wednesday, 4 June 2003 17:15:58 GMT

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