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Re: removing [appearance of] constraints on 'resource' [024-identity]

From: Al Gilman <Alfred.S.Gilman@IEEE.org>
Date: Tue, 25 May 2004 10:51:57 -0400
Message-Id: <p06020401bcd9095a6867@[10.0.1.2]>
To: uri@w3.org

At 7:25 PM -0700 5/24/04, Roy T. Fielding wrote:
>   Please, just focus your comments
>on the change request that Dan made.

Good.

>The question is: should the term "resource" apply to those things
>that have not yet been named or described within any system?

Yes.

Rather, let me give you a Yankee answer.  The question that
should determine this is "Do you need the restricted term
to say clearly anything that you need to say in this document?"
I first answered 'yes' to the broader sense for 'resource' because
I don't think that anything in the general public form or generic processing of
URIs as specified in this document requires that the term 'resource'
be limited to "things for which a URI has been coined to identify them."

I would  suggest rather that we use

"a resource" -- to refer to anything anyone might wish to coin a URI for
(for which simply 'anything' is a serviceable plain-english short form)

and when we want to be more narrow, use the definite article as in:

"the resource identified by a URI"

or

"the resources that have URIs"

>This has no impact on URI technology because assigning a URI is
>naming that thing, and thus anything assigned a URI would be a
>resource under either definition.

So the dispositive argument is that the restriction is not required
by the specification and should not be asserted or implied.

[further down...]

>So, the difference that Dan is asking for is that "resource" include
>those things that have not yet been named or described.  Dan, is there
>a significant reason why you changed tense from "A resource can be
>anything" to "what is a resource" in the last sentence?

Yes, this gets to the heart of the matter. The resource-ness
generally (but not always) pre-exists; hence this quality is referred
to simply in the present tense, not in a clause expressing a
potentiality.

Because this paragraph is non-restrictive, and heuristic in nature, it
is best that our diction be guided by the preponderance of cases
and not strain to be definitive.

The specification does not (as I believe Roy said) in any way
restrict what a URI may refer or identify. Limiting the use of the
term 'resource' in the specification to those things that have a URI
is a gratuitous constraint, it introduces a Term of Art where none is
required and thus loses on the grounds of Occam's Razor. This is
Norm's answer: it introduces a digressive and non-contributory
restriction that diverts the reader's attention from the business at
hand.

The general-English sense of 'resource' is "something of potential
utility."  While sometimes it is the distinction itself between the URI
and other URIs that is of value without benefit of a valuable referent,
still the more common case is that there is somethign that already
posessed potential utility, and assigning it a URI  enhances
but does not create the utility. So most often the thing is a resource
both before and after someone coins a URI to refer to it. It makes it
something of more ready utility, but does not change it into the
class of things of potential utility.  Except in the case of opaque
correlation keys.  That's a valid, but not the general, case of where
the utility comes from.

[yet further down]

>I could add more disclaimers to the effect that this definition
>does not affect the nature of a resource, since anything can
>be named or described, but I'd like to know if that is sufficient,
>or if it is actually folks intent to say that things which have
never been named or described are resources.

Actually, it is more to the point to change the opening sentence in
the display-list where the intended sense of 'resource' is discussed.
Note I do not say 'defined,' as this is not a definition, the
*specification* contained in this document does not in any way depend
on restricting the nature of the 'thing' 'identified' by the URI. We
just need to make the non-restriction more clear.

Where it now says

<quote cite=
"">
    Resource
       Anything that has been named or described can be a resource.
</quote>

It is true that this language does not restrict what may be regarded
as a 'resource' in any way. The problem is that a casual reader may
think it does.

So don't use language that talks about what may or may not be a resource.
There's no 'there' there.

Use language that clearly leaves wide open what may have a URI coined
to refer to it.

<draft>

Resource
<hangingIndent>
A URI may be coined to identify anything for which the coiner feels
it would be of benefit to have a URI to retain or communicate. There
is no restriction in or by this specification on what the 'resource'
identified by a URI may be.

The value added by coining this URI may lie in the latent and
intrinsic potential utility of the 'resource' so identified, or
in the distinction between the thing identified and other things.

</hangingIndent>
</draft>

With best regards,

Al

>As with all other discussions on this topic, the messages are
>not being constructive to the issue at hand.  The question is not
>whether resources can exist without being assigned URI, nor whether
>a URI scheme can be defined that identifies abstract resources
>through indirection.  Both of those issues are unaffected by the
>change of wording that I made for draft 05. Nor, for that matter,
>does this have any relation to httpRange-14 other than the fact
>that it came up during a discussion of that TAG issue, and this
>issue is not at all present in the discussion/diagrams we talked
>about at the last TAG meeting.  Please, just focus your comments
>on the change request that Dan made.
>
>The question is: should the term "resource" apply to those things
>that have not yet been named or described within any system?
>This has no impact on URI technology because assigning a URI is
>naming that thing, and thus anything assigned a URI would be a
>resource under either definition.
>
>The only real effect is that the current wording allows the editor
>(i.e., me) to address complaints that either:
>
>   1) "resource" as used does not correspond the language definition; or
>
>   2) one cannot reference what has not been named or described, and thus
>      no system can make use of such a thing directly (i.e., aside from
>      aggregation as a named set of things), and thus it is not a resource.
>
>On Monday, May 24, 2004, at 01:53  PM, Dan Connolly wrote:
>>Regarding...
>>
>>"Anything that has been named or described can be a resource."
>>-- http://www.gbiv.com/protocols/uri/rev-2002/rfc2396bis.html#overview
>
>For context, the definition of draft 05, in full, is:
>
>    Resource
>       Anything that has been named or described can be a resource.
>       Familiar examples include an electronic document, an image, a
>       service (e.g., "today's weather report for Los Angeles"), and a
>       collection of other resources. A resource is not necessarily
>       accessible via the Internet; e.g., human beings, corporations, and
>       bound books in a library can also be resources. Likewise, abstract
>       concepts can be resources, such as the operators and operands of a
>       mathematical equation, the types of a relationship (e.g., "parent"
>       or "employee"), or numeric values (e.g., zero, one, and infinity).
>       These things are called resources because they each can be
>       considered a source of supply or support, or an available means,
>       for some system, where such systems may be as diverse as the World
>       Wide Web, a filesystem, an ontological graph, a theorem prover, or
>       some other form of system for the direct or indirect observation
>       and/or manipulation of resources. Note that "supply" is not
>       necessary for a thing to be considered a resource: the ability to
>       simply refer to that thing is often sufficient to support the
>       operation of a given system.
>
>>Based on discussion with TimBL and Roy and a few others,
>>as well as review of this issue...
>>
>>024-identity Resource should not be defined as anything that has
>>identity
>>http://www.gbiv.com/protocols/uri/rev-2002/issues.html#024-identity
>>
>>it seems more straightforward to just say
>>
>>	A resource can be anything; familiar examples include an 
>>	electronic document, an image, a service (e.g., "today's 
>>weather
>>	report for Los Angeles"), and a collection of other resources,
>>	but there is no constraint on what is a resource.
>
>So, the difference that Dan is asking for is that "resource" include
>those things that have not yet been named or described.  Dan, is there
>a significant reason why you changed tense from "A resource can be
>anything" to "what is a resource" in the last sentence?
>
>>Public discussion of http://www.w3.org/TR/webarch/ suggest that this
>>unconstrained definition of 'resource', along with a separate term
>>for a smaller set of "information resources" is a useful way to
>>describe the role of URIs in Web Architecture.
>>(we haven't finished the text yet, but you can see a
>>diagram at
>>   http://www.w3.org/2004/05/URI-space-small.png
>>   http://www.w3.org/DesignIssues/diagrams/URI-space.svg
>>and some notes on the discussion at
>>   http://www.w3.org/2004/05/14-tag-summary.html#httpRange-14-1 )
>
>A public discussion between Pat Hayes and various members of the
>W3C TAG produced comments suggesting that Dan's use of the term
>"resource" was a synonym for "thing" (not just that all things
>can be resources, but all things *are* resources) and yet the
>webarch document simultaneously describes resources as both
>anything and as a constrained set of things that TimBL refers to
>as "information resources".  One of Pat's earlier comments on the
>webarch document was that the definition of resource, as obtained by
>reference to rfc2396bis, is synonymous with "thing" and does not
>correspond to the English definition of "resource".  Since I do
>not view them as synonyms, something was amiss, and thus the
>change from draft 04's
>
>   "Anything that can be named or described can be a resource."
>
>   "Anything that has been named or described can be a resource."
>
>In other words, that there exists a set of things which are not
>yet resources for any system, and thus comments to the effect
>that "how can an unspecific particle of sand on some beach
>be a resource?" are answered.
>
>>The unconstrained definition of 'resource' is also what was imported
>>into the RDF specification:
>>
>>   The things denoted are called 'resources', following [RFC 2396], but
>>   no assumptions are made here about the nature of resources; 'resource'
>>   is treated here as synonymous with 'entity', i.e. as a generic term
>>   for anything in the universe of discourse.
>>     -- http://www.w3.org/TR/rdf-mt/ aka
>>	http://www.w3.org/TR/2004/REC-rdf-mt-20040210/
>
>Here, I simply have to disagree.  RDF says that the things denoted are
>called resources, which is equivalent to saying that the things named
>or described by RDF are resources.  There is no difference between that
>and what is defined in draft 05, so I do not see the conflict.  The
>draft 05 definition does not, in any way, constrain the nature of
>resources, since anything can be named or described.  It simply
>differentiates between what has been named or described and those
>things that have not.
>
>In discussion on the telephone, my recollection is that Dan suggested
>that all numbers within the Real number set must be resources.  I have
>no idea why that needs to be the case, since mathematics has no such
>requirement.  Real numbers as a set is a resource.  Any specific real
>number that one might care to enumerate is a resource.  But, because
>the set is non-numerable, the only way to refer to every number in the
>set is to use existential qualifiers like "There exists ..." and
>"For all ...".  Those qualifiers allow one to indirectly refer to
>each/every member of a set by reference to the set itself.
>I don't consider that sufficient to call each and every real number
>a resource, at least not until someone creates a name or description
>that distinguishes that real number from all others.  However, I may
>just have misunderstood Dan's point.
>
>In any case, I do not know of any system or specification that
>breaks due to the draft 05 definition, nor of any description of
>the Web or URI space that requires the set of all resources to be
>greater than the set of named or described things.  I remain
>unconvinced that changing it to "anything can be a resource" is
>sufficient to address prior complaints that some things
>are not resources (i.e., are not usable, referenced, or denoted
>by any system).
>
>I could add more disclaimers to the effect that this definition
>does not affect the nature of a resource, since anything can
>be named or described, but I'd like to know if that is sufficient,
>or if it is actually folks intent to say that things which have
>never been named or described are resources. [In that case, I'll
>have to agree with Pat's assertion that such use of the term
>resource is just plain confusing and should be defended by those
>who think it makes sense.]
>
>....Roy
Received on Tuesday, 25 May 2004 11:23:55 UTC

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