Re: resources and URIs

TimBLs writes:


  <rdf:Description
  rdf:about="http://chandra.harvard.edu/NGC/ngc1068"
  rdf:type="http://chandra.harvard.edu/AOtype/Activegalaxy7"
  </rdf:Description>



  No, that would be illegal by my way of thinking. 

But this is already what alot of folks do. Trying to mandate otherwise is
a bit like re-writing the Web and pulling the rug out from under existing
users, no?

If the goal of the TAG is to document the Web as it presently "hums along
successfully" then it will have to accept usage such as the above.

  http://chandra.harvard.edu/NGC/ngc1068 is an information resource.
  You would expect

  <rdf:Description
  rdf:about="http://chandra.harvard.edu/NGC#ngc1068"
  rdf:type="http://chandra.harvard.edu/AOtype/Activegalaxy7"
  </rdf:Description>


Err. Don't you mean something like

http://chandra.harvard.edu/AOtypes.rdf#Activegalaxy7

Surely, a class is an abstract resource and thus surely must be denoted
by a URIref with fragId, no?

;-)


  or, in the http://chandra.harvard.edu/NGC information ressource,,

  <rdf:Description
  rdf:about="#ngc1068"
  rdf:type="http://chandra.harvard.edu/AOtype/Activegalaxy7"
  </rdf:Description>

  where you can see that local identifiers can be used to refer to abstract things,

And how then do you conveniently refer to structural 
components of documents?

Using fragIds to refer to resources that have no relation
whatsoever to whatever might be referred to by the base
URI seems to me to be both unnecessary, unjustified, and
quite the hack. 

  because that is what the RDF language spec says.

Yeah. Pity. I think we got that one wrong.  I was myself uncomfortable with
it from the start. It feels like just so much smoke and mirrors...



  Also, the fact that an identifier can be composed, using "#", of a term used in a document combined with the global identifier for the document in order to construct a global identifier for the thing identified by the term, while so simple is subject to a lot of criticism. But it works and resolves these issues - even if sometimes the document is imaginary.

I see it creating more issues than it solves

c.f. http://lists.w3.org/Archives/Public/www-tag/2003Jul/0173.html

and also strikes me as an attempt to solve a problem that does not really exist. 

Taking a view as defined in

http://lists.w3.org/Archives/Public/www-tag/2003Jul/0172.html

there is no reason why an http: URI without fragId cannot be used to denote 
anything whatsoever in the universe.

Regards,

Patrick

--

Patrick Stickler
Nokia, Finland
patrick.stickler@nokia.com