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Re: Troublesome relations

From: Thomas B. Passin <tpassin@comcast.net>
Date: Tue, 19 Oct 2004 08:55:36 -0400
Message-ID: <41750EC8.2010807@comcast.net>
To: www-rdf-interest@w3.org

Reto Bachmann-Gmuer wrote:

> I'm probably just missing the problem, but can't just any n-order 
> predicate like predPQ(a, b, c) be reduced to _1(resPredPQ,a), 
> _2(resPredPQ,b), _3(resPredPQ,c)?

No, not when the n-order predicate inherently represents a relation 
between two or more things.  In your decomposition, any one of the three 
reduced expressions could be changed or falsified without affecting the 
other two.  But when the original predicate concerns related things, one 
can't be changed without affecting the value of the other(s) as well.

Say that there is a marriage between John and Sally.  The marriage as a 
concept (or a legal state, for that matter) is concerned with a 
relationship between the two people.  It cannot be carved up into binary 
relationships without doing serious damage to the basic concept.  John 
can be "married", and Sally can be "married" (binary predicates).  But 
the thing that brings them into the relationship, the marriage, 
inherently involves the two of them, and that is not binary.

Cheers,

Tom P

-- 
Thomas B. Passin
Explorer's Guide to the Semantic Web (Manning Books)
http://www.manning.com/catalog/view.php?book=passin
Received on Tuesday, 19 October 2004 12:54:11 GMT

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