xml-dev - RE: Begging the Question (the novel)

[Jonathan Borden <jborden@mediaone.net>]

Lisa Rein wrote:
>
> However, I probably gat asked that question from throughly puzzled
> students more than anything else when I was teaching:  "Where does the
> the namespace URI go to?" (Um. Nowhere.  I just looks like a URI.  It
> isn't one.)
> Why doesn't it go anywhere?  Could it go somewhere?  (No.  It could say
> "ooga booga" and it would still work.)
> Have I ever thought about maybe having it go somewhere?......(You get
> the message)

	This is perhaps the crux of the confusion. The correct answer is that every
URI points to an abstract location in URI space. A namespace URI *is* a URI
(reference), but not all URIs need be URLs, or used as URLs. "an abstract
location in URI space" is not an easy to understand concept for beginning
students, but perhaps it is not a concept so hard to understand when
properly explained. I might use an example from Dublic Core Metadata where a
URI references a name:

	"http://www.purl.org/...#Creator" What does this URI reference? It
references the *concept* of the creator of the document. It is a pointer to
a location on an abstract directed graph of URIs (and I would explain this
by drawing circles and arrows).

	Where a URI points to must be distinguished from what is found when a URI
is resolved into a network entity (i.e. what you get back at the end of the
HTTP GET request). In the above case you will get a document describing
Dublin Core Metadata which will have an identifier "Creator" describing the
term.

	For example you may create the URI
http://www.finetuning.com/LisasVocabulary#Sheesh which references a concept
but cannot be dereferenced or resolved into a physical document fragment.
But the URI reference does reference the (abstract or not so abstract :-)
concept.

Jonathan