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Re: RDDL possibilities

• To: Jonathan Borden <jborden@m...>
• Subject: Re: RDDL possibilities
• From: John Cowan <jcowan@r...>
• Date: Fri, 18 Jan 2002 16:54:00 -0500
• Cc: xml-dev@l...
• References: <E16RR2y-0001Ea-00@m...> <01b001c1a059$a71b6b10$0a2e249b@n...>
• User-agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.6) Gecko/20011120

Jonathan Borden wrote:


> In this case an SI is the same as a URI.


Let's make careful distinctions here.  The SI is the *resource*
named by the URI, not the URI itself.  Resources and URIs are
1-1, so this distinction isn't as important as it could be.


> If this is the case then, yes RDDL uses SIs. Steve Newcomb and I once had a
> discussion regarding the difference between a TM: "subject" and an RDF:
> "resource". My understanding was roughly that an RDF "resource" encompasses
> both a TM: "subject" as well as a "topic".


A subject is anything you can talk about, whether it is computer
accessible or not (for that matter, whether it exists or not --
"Don Quixote" is a perfectly good subject).

A subject can be identified (distinguished from other
subjects) in one of two ways:

1) It *is* a resource named by a URI
2) It is *indicated*, conventionally, by one or more resources
    named by URIs.  These resources are SIs.

So the subject "the W3C" is *identified* by the resource
whose URI is "http://www.w3c.org".

The different subject "the home page of the W3C" just *is*
the resource whose URI is "http://www.w3.org".

The subject "John Cowan" (me) could be identified by the
resources whose URIs are "mailto:cowan@c...";,
"mailto:jcowan@r...";, and "http://www.ccil.org/~cowan".

A *topic* OTOH is an element in a topic map that corresponds with a
subject.  In a properly merged topic map, topics and subjects are 1-1.

> Perhaps a URI published in a publically available RDDL document, makes a PSI
> then?


In effect, yes.

-- 
Not to perambulate             || John Cowan <jcowan@r...>
    the corridors               || http://www.reutershealth.com
during the hours of repose     || http://www.ccil.org/~cowan
    in the boots of ascension.  \\ Sign in Austrian ski-resort hotel

• References:
  • Re: RDDL possibilities
    • From: John Cowan <cowan@m...>
  • Re: RDDL possibilities
    • From: "Jonathan Borden" <jborden@m...>

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