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Re: relationship of rdfs:Literal to rdfs:Resource

From: Garret Wilson <garret@globalmentor.com>
Date: Sun, 14 Sep 2003 08:27:34 -0700
Message-ID: <3F6488E6.2060005@globalmentor.com>
To: Graham Klyne <GK@ninebynine.org>
Cc: www-rdf-interest@w3.org

Hmm, this is giving me even more food for thought. Your responses lead 
me to more questions:

Graham Klyne wrote:
> Syntactically, literals and URI references are distinct entities in an 
> RDF graph, but they both denote things drawn from a set of resources.

1. Let me see if I understand this correctly: literals and URI 
references are syntactically distinct. The things they represent are all 
resources---the things literals represent (rdfs:Literal) are a subset of 
the things URI references represent (rdfs:Resource). Right?

> So, any value (e.g., the number 10) which might be denoted by a literal 
> (e.g. "10"^^xsd:integer) could also be denoted by a URI (e.g. I might 
> define the URI ref http://www.ninebynine.org/2003/09/number#_10 to have 
> the number 10 as its intended denotation), and while they remain 
> syntactically distinct entities, in the interpretation intended by my 
> hypothetical definition, (and the presumed definition of xsd:integer) 
> they would denote the same number 10.

2. Does each instance of the plain literal "10" always refer to the same 
identical resource?

3. Does each instance of the typed literal "10"^^xsd:integer always 
refer to the same identical resource?

4. How can I assert properties of the resources indicated by the plain 
literal "10"? (If "10" really represents a resource, why can't that 
thing have properties, too?)

5. If I wanted to http://www.ninebynine.org/2003/09/number#_10 to refer 
to the resource represented by "10"^^xsd:integer, how would I do that in 
a graph (via RDF+XML)? Why must I force the RDF processor to have some 
sort of outside predefined knowledge to associate URIs with resources 
designated by literals? If I can associate URIs with resources in a 
graph, and literals stand for resources, why can't I associate a URI 
with the resource designated by a literal?

Garret
Received on Sunday, 14 September 2003 11:27:50 GMT

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