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Re: Namespaces wihtout "#" Was: Few CWM Bugs

From: Tim Berners-Lee <timbl@w3.org>
Date: Sun, 23 Dec 2001 23:09:21 -0500
Message-ID: <01fb01c18c30$c4515d30$f8061812@CREST>
To: "Jonathan Borden" <jborden@mediaone.net>, "Dan Brickley" <danbri@w3.org>
Cc: "Sean B. Palmer" <sean@mysterylights.com>, "Dan Connolly" <connolly@w3.org>, <www-rdf-interest@w3.org>
True.  A resource for a non-HTTP space can be whatever that URI space says
it
is.  It is just HTTP which really creates a world of documents.

mailto:  for example, defines a space of mailboxes which are not documents.
I should have limited what I said to the http: space.

Tim

----- Original Message -----
From: "Jonathan Borden" <jborden@mediaone.net>
To: "Tim Berners-Lee" <timbl@w3.org>; "Dan Brickley" <danbri@w3.org>
Cc: "Sean B. Palmer" <sean@mysterylights.com>; "Dan Connolly"
<connolly@w3.org>; <www-rdf-interest@w3.org>
Sent: Saturday, December 22, 2001 10:39 AM
Subject: Re: Namespaces wihtout "#" Was: Few CWM Bugs


> Tim Berners-Lee wrote:
> > >
> > > > The second issue is more significant.   In my worldview,
> > > > (which I claim to be (a) consistent and (b) useful)
> > > > http://example.org/x is a document.  You can't reuse
> > > > its URI for an abstract thing without a change to HTTP.
> > >
> > > In-principle plausible, although _please_ define "document".
> >
> > I uyse the term "document" because unfortunately "resource" has been
> > used differently in URI and RDF specs.   I mean by "document"
> > "resource" as in URI.   DAML uses the term "Thing" to mean what RDF
> > terms a resource.
>
> This is really helpful, yet when I read the RFC 2396 definition of a
> resource I don't see how a resource can be _limited_ to only things which
> are documents:
>
> "A resource can be anything that has identity. 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. Not all resources are
> network "retrievable"; e.g., human beings, corporations, and bound books
in
> a library can also be considered resources. "
>
> This language clearly states, to my very best reading, that a _document_
is
> a subClass of a _resource_ and a _human being_ is another subClass of
> _resource_. This is why I cannot understand why a plain old URI (i.e.
> without fragment identifer)  cannot identify a person. Perhaps you are
> saying that the _type_ of resource is indicated by the URI scheme? i.e.
that
> people would be indicated e.g.
>
> person://smith/joe
>
> >
> > When the content-type is RDF or N3, then a document can be used
> > to describe people and planes and ideas.  These can be identified
> > (in N3) by using the localname of concept within the document
> > as a fragment identifier.  (I think the same should be true of RDF/XML).
>
> Ok, I buy this. Here you say that people, places and things can be
> identified by URI References. This still does not solve the problem that
RFC
> 2396 says what URIs themselves may identify...
> >
> > >.The distinction
> > > is only useful if it can be defined clearly enough to implement to.
> >
> > Well,  you certianly can't return a person across the net, so the
> > distinction is
> > not that fine ;-)
>
> Again, RFC 2396 explicitly does not limit resources to things that are
> network retrievable, so I need more guidance here.
>
> Perhaps the problem is that many people treat RFCs as axioms and in trying
> to understand how 'logic on the Web' will work in practice,
inconsistencies
> are problematic.
>
> Jonathan
>
Received on Sunday, 23 December 2001 23:09:23 GMT

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