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Possible confusion in Reference

From: Jeff Heflin <heflin@cse.lehigh.edu>
Date: Fri, 25 Apr 2003 17:05:15 -0400
Message-ID: <3EA9A30B.6A6C702E@cse.lehigh.edu>
To: WebOnt <www-webont-wg@w3.org>

I was looking through the reference today and I think the description of
owl:sameAs in section 5.2 is misleading. It says:

In OWL Full, where class can be treated as instances of (meta)classes,
we can use the owl:sameAs construct to define class equality, thus
indicating that two concepts have the same intensional meaning.

(btw, note "where class can" should be "where classes can")

I believe that in fact sameAs has an even stronger interpretation: that
the classes are the same resource! (Peter, please correct me if I'm
wrong here). Note the implications of this. If one class has some
meta-property, such as author, label, last change date or whatever, then
any class that is "sameAs" it also has the same values for those
properties. Chances are, this is not what is usually intended. However,
the reference implies this is the preferred way to map two class
concepts that have the same intensional meaning. Unfortuantely, OWL
doesn't really have a mechanism for truly stating that two classes have
the same intensional meaning. That would require us to somehow separate
meta-properties that are about a particular resource from those about
the concept it denotes. Anyway, I think this issue should be explained
and <footballTeam owl:equivalentClass us:soccerTeam /> should be the put
forth as the preferred way for mapping these two classes.

Jeff
Received on Friday, 25 April 2003 17:05:20 GMT

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