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Re: Resources and URIs

From: Roy T. Fielding <fielding@apache.org>
Date: Mon, 28 Apr 2003 17:54:44 -0700
Cc: uri@w3.org
To: pat hayes <phayes@ai.uwf.edu>
Message-Id: <2AC857DC-79DD-11D7-B0C5-000393753936@apache.org>

> Skolemized URIs work just fine. The existing Web protocols and  
> conventions are perfectly adequate, in fact, to handle this. They are  
> BETTER than the current RFC 2396 prose says they are.

You have said that a few times, but the problem isn't what RFC 2396 says
but rather what you assume it means.  You asked for a definition of
identity, and I gave it, at which point you asked me to define all
of the words within that definition.  That is nonsensical.  Furthermore,
your entire argument boils down to that we should consider changing
the definition, which of course is why the issue is on the issues list
and was listed as "pending".  Everything that has been said in this
discussion is just a verbose variant of what was already said and
summarized within that issue.  That is why I have been and will continue
to be brusque in my responses: I am sick of reading fifty paragraph
mails for a request that has already been conveyed in one paragraph.

To answer your real question: the definition in RFC 2396 means exactly
what you wish it to mean.  Resources are things that have identity --
not one unique identity, but an identity that is being referenced for
the sake of denotation.  That is a common English word and the way I
used it in the sentence does not allow for any other reasonable
interpretation, including the one Miles described about the identity
axiom in mathematics.  After reading this discussion, it appears that
you grasp the concept without any problem, but you are being faced with
other arguments that fail to grasp it or are using the multiple  
potential
definitions of the term "identity" as some bizarre excuse to claim that
a URI defines the resource's identity.  Okay, that was Miles point as
well, so we can replace use of that term with the definition.  However,
I am not going to proceed recursively down the ontological tree until
everyone is satisfied -- I just want to get it to the point where the
intended definition is distinguished from those that are not intended,
even if I can't understand how people could confuse them now.

I do not accept the argument that nothing should be said about resources
in the spec.  The URI-WG tried that originally and failed miserably --
dozens of identifier schemes and related projects were created based on
false assumptions about the limits of resource.  Years of effort were
wasted in attempts to create "better identifiers" that didn't suffer
from the imagined limitations of existing identifiers.  That is why
the definitions were added in 1997, and I'd rather hash this out in
one place than have to explain it again in every single working group.

In fact, I don't think the problem you are describing has to do with
confusion over "identity" at all, but rather what it means to "identify"
a resource.  In that sense, it is unfortunate that they are called
identifiers, but I can improve that definition as well.  In fact, I
already did that yesterday:

http://www.apache.org/~fielding/uri/rev-2002/ 
rfc2396bis.html#rfc.section.1.1

If anyone has comments on that text, please be specific.  Otherwise,
this issue is closed.

....Roy
Received on Monday, 28 April 2003 20:52:19 GMT

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