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RE: web proper names

From: Benjamin Nowack <bnowack@appmosphere.com>
Date: Tue, 21 Sep 2004 19:06:34 +0200
To: "Hamish Harvey" <david.harvey@bristol.ac.uk>
Cc: RDFInterest <www-rdf-interest@w3.org>
Message-ID: <PM-EH.20040921190634.A533.6.1D@>

On 21.09.2004 17:13:26, Hamish Harvey wrote:
>On Tue, 21 Sep 2004 17:49:04 +0200, "Benjamin Nowack"
><bnowack@appmosphere.com> said:
>> On 21.09.2004 14:24:19, Hamish Harvey wrote:
>> >When a (URI qua symbol) is to indicate a non-retrievable resource, such
>> >as the Eiffel Tower, it is then possible to place an eg HTML document to
>> >be retrieved using that URI as a (URI qua retrival path), and it is
>> >precisely the fact that humans can do this in order to get a hint as to
>> >what a (URI qua symbol) is supposed to identify that leads to the
>> >argument that one should always use http URIs. This document is of value
>> >only to humans.
>> I'd disagree on that. The moment you put a dereferencable document at
>> that location, people might want to start talking about it, and we end
>> up with an ambiguous URI. So I'd say, whenever you want to use a URI
>> for a non-web resource, don't put a web resource at (exactly) the same
>> place. This doesn't mean that we can't provide information, but we have
>> to make sure (via URIQA, redirects & Co.) that we don't lose the URI's
>> disambiguity.
>_:dereferenceableThing ex:resultOfDereferencing
>"http://www.paris.org/Monuments/Eiffel"^^xsd:anyURI .
>and say anything you want to about _:dereferenceableThing. No ambiguity.
>People can talk about the document, they just need to make sure they are
>talking about the document and not the thing indicated by the URI.
Fair enough, although the "just need to make sure" is a bit vague if
"http://www.paris.org/Monuments/Eiffel" was an obvious web page.
But basically that's exactly what I tried to say in the other post.
We need an agreed-on way to handle resource descriptions and their
As there are so many possibilities already I wouldn't suggest adding
another one, though. And using a URI as a Literal doesn't really help
if we want to unambiguously identify the resources/repesentations we
talk about. You'd have to make ex:resultOfDereferencing an IFP which
would probably not be acceptable to OWL DL folks.

>If you are going to say "don't put a web resource at the same place"
>then it would seem to me to be illogical to use http URIs; that then
>moves into a different debate. To humans, being able to dereference a
>URI and find some explanation of what that URI qua symbol is intended to
>indicate is very valuable indeed, and I was starting from the assumption
>that http URIs would be used, as symbols, to indicate non-web resources,
>precisely because this meant it was possible to post an explanatory web
That's why I wrote "(exactly) the same place". There are ways to make it
possible to dereference a URI ref to get a (potentially human-oriented)
representation without overloading the URI. A simple (not perfect) 
example is SlashRedirect (There should still be a related page in the
esw wiki). Another solution could be URIQA-enabled browsers.


Benjamin Nowack

Kruppstr. 100
45145 Essen, Germany

Received on Tuesday, 21 September 2004 17:06:46 GMT

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