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Re: [httpRange-14] What do HTTP URIs Identify?

From: Chris Lilley <chris@w3.org>
Date: Sat, 3 Aug 2002 22:06:58 +0200
Message-ID: <120115013562.20020803220658@w3.org>
To: www-tag@w3.org, "Joshua Allen" <joshuaa@microsoft.com>
CC: Bill de hÓra <dehora@eircom.net>, "Tim Bray" <tbray@textuality.com>

On Friday, August 2, 2002, 8:46:15 PM, Joshua wrote:

>> > Semantic Web has to be able to tolerate the fact that you can't know
>> > what a resource is, and thus different parties may not have a shared
>> > perception of this, just like the Web needed 404 to work. -Tim
>> Some of us have been saying just this for a while now. You can't design
>> ambiguity out of a system this size or simply wish it away with by
>> waving axioms at people, however desirable they are.

JA> I wonder why this is so hard for people to understand.

JA> Ambiguity is inevitable.  OK?  Is everyone happy now that we agree on this?

JA> But I am puzzled how this has ANY bearing on the following "axiom":

JA> "If two people independently use the same URI as an identifier,
JA> they should be able to have a reasonable degree of confidence that
JA> they are identifying the same resource.

Its an axiom, but a circular or tautologous one. The resource has no
independent existence - it comes into existence only by a URI being
created for it. So the axiom is of the form 0+0, ie it  is true, but
does not say very much. It says that what a URL points to is what it
points to.

JA> People should not be required to parse, dereference, or otherwise
JA> acquire any *additional* disambiguating information to provide
JA> this basic guarantee.

Right (unless they want) to talk about resource variants or resource
contents in a particular variant at a particular point in time

 Chris                            mailto:chris@w3.org
Received on Saturday, 3 August 2002 16:07:28 UTC

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