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Re: relationship of rdfs:Literal to rdfs:Resource

From: Garret Wilson <garret@globalmentor.com>
Date: Sat, 27 Sep 2003 19:32:55 -0700
Message-ID: <3F764857.8040107@globalmentor.com>
To: Benja Fallenstein <b.fallenstein@gmx.de>
Cc: Sandro Hawke <sandro@w3.org>, Graham Klyne <gk@ninebynine.org>, www-rdf-interest@w3.org

Benja

Benja Fallenstein wrote:
> Well, if dc:creator is defined as having as its object the creator of 
> its subject, then you have stated above,
> 
>     uri:x-example-document was created by the character string
>     G-a-r-r-e-t-_-W-i-l-s-o-n.

I thought I stated, "uri:x-example-document was created by the resource 
represented by the lexical form G-a-r-r-e-t-_-W-i-l-s-o-n."

Referring again to 
http://www.w3.org/TR/1999/REC-rdf-syntax-19990222/#basic , are you 
proposing that Ora Lassila (who should know, being the editor of the 
first RDF specification) claimed that the web page 
http://www.w3.org/Home/Lassila was created by the character string 
O-r-a-_-L-a-s-s-i-l-a? (Have the semantics of RDF literals have changed 
a lot since 1999?)

> At least
> 
>     http://www.w3.org/TR/rdf-concepts/#section-Literals
> 
> says that
> 
>     Literals are used to identify values such as numbers and dates by
>     means of a lexical representation.
> 
> and I don't think that "values such as numbers and dates" includes 
> people.

I would take "such as..." to denote a subset, meaning the set containing 
numbers and dates but not necessarily exclusive to people.

Surely you're not asserting that literals can *only* denote numbers and 
dates---under that definition, a literal could not represent a character 
string.

> Besides, if you allowed a literal "Garret Wilson" to identify a 
> person, you would have a *real* problem: What if *I* used it to denote a 
> *different* person?

We already have this problem---what if I used "999" to refer to the 
integer value 1000-1, and *you* used 999 to refer to the character 
string 9-9-9? Then Ora Lassila comes along and uses "999" to refer to a 
date, defined as the number of seconds past 22 February 1999 (sorry, 
Ora). ;)

> So hopefully, for this example, dc:creator is actually defined as having 
> as its object the *name* of the creator of its subject.

I don't know what that buys us---let's define "999" as referring to the 
*name* of the integer value 1000-1, and define "999" as referring to the 
*name* of the date denoted by the number of seconds past 22 February 
2999. Doesn't the term "lexical form" in some sense already mean the 
"name" of the object it reresents?

But maybe I'm wrong and literals are only supposed to be able to 
represent logical number-like things. If so, maybe it could be made a 
little clearer in one of the specs.

This discussion (while fun) is all tangential to the main point: I want 
to identify my resources by reference URIs (I'll even take node IDs), 
even if I've referred to them using some lexical notation.

Cheers,

Garret
Received on Saturday, 27 September 2003 22:33:27 GMT

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