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RE: Mistaken identity?

From: John Black <JohnBlack@deltek.com>
Date: Wed, 23 Jun 2004 08:44:00 -0400
Message-ID: <CBEA695878CA104ABC6E74C6B176927507BD64@DLTKVMX2.ads.deltek.com>
To: "Thomas B. Passin" <tpassin@comcast.net>, <www-rdf-interest@w3.org>

> From: Thomas B. Passin
> Sent: Wednesday, June 23, 2004 2:14 AM
> 
> Jon Hanna wrote:
> 
> >> Just because you use a particular URI as an rdf identifier doesn't
> >>  automatically mean that the rdf resource is equal to the web page 
> >> returned when you dereference the uri.
> > 
> > 
> > No, it is equal to the resource a representation of which 
> is returned
> >  when you dereference the URI.
> > 
> 
> No, sorry, but that just isn't so.  Let me quote from one of the RDF
> Recommendations, the RDF Semantics document -
> 
> "The semantics does not assume any particular relationship between the
> denotation of a URI reference and a document or Web resource which can
> be retrieved by using that URI reference in an HTTP transfer protocol,
> or any entity which is considered to be the source of such documents."
> 
> It goes on to say this -
> 
> "Such a requirement could be added as a semantic extension, but the
> formal semantics described here makes no assumptions about any
> connection between the denotations of URI references and the uses of
> those URI references in other protocols."
> 

I believe Thomas is correct. Furthermore, IMHO, I think development of 
that semantic extension, defining that "particular relationship", is the 
greatest problem facing the semantic web. I think the problem is so 
important it should be added as the eighth of the Millennium Prize Problems,
http://encyclopedia.thefreedictionary.com/Millennium%20Prize%20Problems
and the solvers awarded $1,000,000.00.

Here is how Tim Berners-Lee puts it,
[[
An "RDF machine" is presumably one which draws inferences in ways which 
have been authorized in the RDF spec.  A "URI machine" is one which 
makes inferences based on what it find in the URI spec.
A very interesting machine is composed of both.
...
So yes, a "pure" RDF machine can b conceived of which only does RDF-MT 
allowed operations.
The semantic web, though uses URIs for a reason.
That's why cwm mixed an RDF machine and a URI machine (which includes 
an HTTP machine).
...
"The semantic web is defined as being built on the web."
]]
http://lists.w3.org/Archives/Public/www-tag/2003Aug/0039.html

So I hereby dub it the "Berners-Lee Hypothesis" problem - to prove the 
hypothesis that there exists a combination of these two technologies 
that creates something far more powerful than the sum of the powers of 
either one.

John Black

> 
> Cheers,
> 
> Tom P
> 
> -- 
> Thomas B. Passin
> Explorer's Guide to the Semantic Web (Manning Books)
> http://www.manning.com/catalog/view.php?book=passin
> 
> 
Received on Wednesday, 23 June 2004 08:44:02 GMT

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