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Re: RDF vocabulary definitions

From: Brian McBride <bwm@hplb.hpl.hp.com>
Date: Thu, 21 Nov 2002 17:49:14 +0000
Message-Id: <5.1.0.14.0.20021121174033.07b9eda8@0-mail-1.hpl.hp.com>
To: "Richard H. McCullough" <rhm@cdepot.net>, "David Menendez" <zednenem@psualum.com>
Cc: "RDF-Interest" <www-rdf-interest@w3.org>

At 08:44 21/11/2002 -0800, Richard H. McCullough wrote:
>It was my impression that "instance" was deprecated, to be replaced by 
>"individual".
>For example, see 
><http://www.w3.org/TR/2002/WD-owl-features-20020729/>http://www.w3.org/TR/2002/WD-owl-features-20020729/ 
>
>
>However, looking at the OWL document again, I see it uses both terms:
>     "Individuals may described as an instance of a Class ..."

If we are talking about RDF, please can we use RDF's terminology.  It might 
be a good idea to note any confusion of teminilogy to both WG's comment 
lists though.

[...]

>
>Here's a simple definition of "individual" and "class".
>An individual is a single concrete existent.

I'd have a little trouble with that I think.  The real number Pi is a 
resource.  Is that a single *concrete* existent?  The set of real numbers 
is a resource - is that a *single* concrete existent?  The set of rational 
numbers is a resource - is that  a single concrete *existent*.

>A class is an abstract group (a mental integration) of two or more similar 
>individuals.

RDFS classes can be empty or have just one member and those members do not 
have to be individuals by your definition.

I'm not quite sure what you are trying to say here.  Are you saying that 
RDFS's use of the term class is different to the way you use the term?  If 
so, fine, I agree.  It also different to the way that Java uses the term, 
so I'm not too bothered so long as we are all clear which variant we 
are  discussing at any one time.  If you are saying therefore its wrong, 
then that is another matter.

Brian
Received on Thursday, 21 November 2002 12:47:46 GMT

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