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sameClassAs vs. sameMembersAs

From: Jerome Euzenat <Jerome.Euzenat@inrialpes.fr>
Date: Thu, 30 Jan 2003 10:57:55 +0100
Message-Id: <a05200f01ba5ea3668de0@[194.199.20.189]>
To: webont <www-webont-wg@w3.org>

Hello,

At 13:02 -0500 29/01/2003, Jim Hendler wrote:
>3.1 Name change on "owl:sameClassAs"  (Guus Schreiber)
>
>Several people have suggested changing the name of sameClassAs to 
>sameMembersAs or some other term more clearly suggesting the 
>extensional nature of this construct.

The name of the constructors should be based on the "intension" and 
not the "extension".

I would even rephrase this in a more defined way: the constructors 
are syntactic units and their name should not be based on the 
interpretation of the terms. The _interpretation_ of sameClassAs is 
the equality of the interpretion of its arguments (and thus the 
equality of the extension of the classes).

This is not something special for sameClassAs but applies to any 
constructors. So, if we want to reconsider the name of sameClassAs, 
we should also do it for the relations and the individuals. If 
relation and individual are syntactic constructs, then the same 
reasoning will lead to reformulating the same...As into something 
closer to the interpretation, what about:

	sameSetOfTupplesAs( relation, relation ) ?

Even if a Class is given by enumeration (oneOf), this is still a 
syntactic unit expressed as a set but this set is not the 
interpretation of that Class (the interpretation is, often, a set of 
the interpretation of the individuals). Then when you write:

	intersectionOf( oneOf( a, b ), class( ... ) )

you are still manipulating syntax, and the class description is not a set.
All constructors have an interpretation, not only the classes.
If people are disturbed by writing

	intersectionOf(Class,unionOf( Class, Class))

I would sugest to come back to:

	and(Class, or( Class, Class ))

[or, less easy, conjunctionOf( Class, disjunctionOf( Class, Class ))]

-- 
  Jérôme Euzenat                  __
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Received on Thursday, 30 January 2003 12:10:32 GMT

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