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Re: subclasses (RDF vocabulary definitions)

From: Brian McBride <bwm@hplb.hpl.hp.com>
Date: Thu, 21 Nov 2002 22:41:08 +0000
Message-Id: <5.1.0.14.0.20021121223944.02eb44f0@0-mail-1.hpl.hp.com>
To: "Richard H. McCullough" <rhm@cdepot.net>, <www-rdf-interest@w3.org>, "David Menendez" <zednenem@psualum.com>

I must be missing something.  I see notation.  I see no explanation.

Brian


At 14:27 21/11/2002 -0800, Richard H. McCullough wrote:
>Brian said:
>
>   [[ll classes are subclasses of themselves.
><<this is true, but RDF Schema should use proper subsets instead of subsets.
>Using subsets logically permits such absurdities as: the set of all men is
>identical to the set of all animals.>>]]
>
>I'm intrigued by that one.  We have a major flaw if that is true.  Care to
>explain?
>I'm going to use some KR notation here because I think you will find it 
>easier to understand.
>Here's the notation
>"is":  man  is  animal          sets are identical
>"iss":  man  iss  animal       man is proper subset of animal
>"iss*": man  iss*  animal      man is subset of animal
>
>iss is the main property used in KR
>iss* is the rdfs:subClassOf property, and its meaning is that
>     either man is animal
>          or man iss animal
>
>and it's also the source of "bragging" about a class being a subclass of 
>itself, i.e.,
>     man iss* man
>     animal iss* animal
>============
>Dick McCullough
><http://rhm.cdepot.net/>knowledge := man do identify od existent done
>knowledge haspart list of proposition
Received on Thursday, 21 November 2002 18:36:15 GMT

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