- From: Tim Berners-Lee <timbl@w3.org>
- Date: Sun, 23 Dec 2001 23:09:21 -0500
- 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 UTC