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RE: Not-subClassOf

From: Peter Crowther <peter.crowther@networkinference.com>
Date: Thu, 24 May 2001 12:56:43 +0100
Message-ID: <B6F03FDBA149CA41B6E9EB8A329EB12D05A2EF@vault.melandra.net>
To: "'jos.deroo.jd@belgium.agfa.com'" <jos.deroo.jd@belgium.agfa.com>
Cc: www-rdf-logic@w3.org
> From: jos.deroo.jd@belgium.agfa.com [mailto:jos.deroo.jd@belgium.agfa.com]
> [pemery@grci.com]
> > I believe that [ a :X, [ daml:complementOf :Y ] ] is a 
> > stronger statement than was
> > required for "a class X is not a subclass of class Y"
> > This method implies there is an instance of class X.  This 
> > may not be true.

> So if there is no instance of class X then X the empty set, no?

Not necessarily; it may simply be that we do not know of (or wish to
represent) an instance of that class.  I should be able to refer to the
class of honest politicians (which is not a subclass of the class of
moderate politicians) without necessarily having to provide evidence that an
honest politician exists or having to describe one.

		- Peter
Received on Thursday, 24 May 2001 07:57:03 UTC

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