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RE: New version of URI Declarations

From: Booth, David (HP Software - Boston) <dbooth@hp.com>
Date: Fri, 29 Feb 2008 02:23:22 +0000
To: Pat Hayes <phayes@ihmc.us>
CC: "www-tag@w3.org" <www-tag@w3.org>
Message-ID: <184112FE564ADF4F8F9C3FA01AE50009E254DB11E9@G1W0486.americas.hpqcorp.net>

Hi Pat,

I think I see your point: without me standing in front of you, pointing to the moon and saying: "I hereby declare that http://dbooth.org/2007/moon/ henceforth refers to *that* moon", my URI declaration cannot be guaranteed to be understood as referring to the actual moon.

That sounds like a valid point, but it doesn't invalidate the notion of a URI declaration.  Mechanically, a URI declaration really only creates an association between a URI and a set of assertions (the "core assertions").  The interpretation of those assertions as describing a particular resource  -- whether you interpret them the same way I do -- is a different issue.  That problem exists regardless of whether one accepts the notion of URI declaration.  URI declarations do not try to solve that problem.

David Booth, Ph.D.
HP Software
+1 617 629 8881 office  |  dbooth@hp.com

Opinions expressed herein are those of the author and do not represent the official views of HP unless explicitly stated otherwise.

> -----Original Message-----
> From: Pat Hayes [mailto:phayes@ihmc.us]
> Sent: Thursday, February 28, 2008 2:56 PM
> To: Booth, David (HP Software - Boston)
> Cc: www-tag@w3.org
> Subject: Re: New version of URI Declarations
> At 10:18 PM +0000 2/27/08, Booth, David (HP Software - Boston) wrote:
>       I've substantially revised and expanded my write-up on
> URI declarations:
>       http://dbooth.org/2007/uri-decl/
>       For anyone interested in issues of resource identity
> and proper use of URIs, I strongly recommend reading it.  If
> you already read an earlier version, this version has added
> sections on granularity, ancillary assertions, why it's
> important to distinguish URI declarations from ancillary
> assertions, and an explanation of how a URI declaration
> establishes resource identity.
>       The abstract:
>       [[
>       A URI declaration permits assertions about a URI's
> associated resource to be classified into two groups: core
> assertions, whch are provided by the URI declaration, and
> ancillary assertions, which are all others.  This distinction
> enables different parties to share a common understanding of
> the associated resource (by accepting the core assertions)
> while making different choices about which ancillary
> assertions to accept. This paper defines these concepts and
> proposes some related best practices and a Web architectural
> rule specifying how URIs for non-information resources can be
> conveniently declared using existing hash or hashless
> (303-redirect) URI mechanisms.
>       ]]
>       As usual, comments are invited.
> OK, you did ask...
> There is a basic problem with this idea and what you say
> about it. It comes to the surface here:
> "Definition: A URI declaration is a set of statements, or
> "core assertions", that authoritatively declare the
> association between a URI and a particular resource.
> A URI declaration is a performative speech act.  (See Cowen's
> message or Wikipedia.)  Its publication by someone who has
> the authority to make the declaration -- the URI owner or
> delegate -- defines the association between a URI and a resource.  "
> Wrong. Or, since a definition can't be wrong: with this
> definition, URI declarations do not exist; in fact, cannot
> possibly exist.
> No amount of just asserting can possibly create an
> association between a URI and a non-information resource,
> (unless it does so via some other URI which is itself
> 'associated' to a resource appropriately, but that just gets
> us into an infinite recursion.) There is no way of forcing a
> purely assertional framework, no matter how complex or large
> it is, to refer to anything non-linguistic or non-symbolic,
> by making assertions in the framework itself. (This can be
> formally stated as Herbrand's theorem: if a set of axioms has
> a satisfying interpretation at all, then it has one entirely
> made of its own symbols.)
> Its not a question of authority. You can have all the
> authority you want: but if all you can do is make assertions
> at me, no amount of authority is going to prevent me
> consistently understanding you as only talking about a
> symbolic world. I won't be rejecting what you tell me: you do
> have the authority to assert it, and I will accept it all as
> true. But it can all be true, and still not refer to what you
> want it to refer to. You can't possibly attach symbols to
> reality by symbolic means (like making assertions using the symbols).
> Just calling this a performative speech act doesn't work,
> either. In order to get a performative to work, you need to
> do something - perform a performative - with the thing
> involved in the act. The things involved in the speech act
> are part of the performance. The performative "I now
> pronounce you man and wife" works, in part, because it is
> said to the man and the wife themselves, in the flesh, so to
> speak. They have to be there to get married. Baptism,
> similarly, attaches a name to a child, and the child has to
> be there to get baptised. As John Cowan points out, in some
> cultures, simply saying "my real name is X' is enough to make
> your name X: but it has to be you that says it. Performatives
> always use indexicals (I, now, you, this) because they always
> need to be performed as part of an act involving the thing or
> person itself (or in some cases a person or thing
> appropriately associated with the thing or person, such as
> someone acting with power of attorney.)
> I could make detailed comments on the rest of the document,
> but this is enough. This idea of 'declarations' of
> non-symbolic, non-computational, non-informational entities
> just does not make sense. You can't declare the moon. Give up
> on the idea, its nonsense.
> Pat Hayes
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Received on Friday, 29 February 2008 02:25:24 UTC

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