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Unique names assumption

From: David Allsopp <d.allsopp@signal.qinetiq.com>
Date: Fri, 02 Aug 2002 11:02:53 +0100
Message-ID: <3D4A58CD.4184077D@signal.qinetiq.com>
To: public-webont-comments@w3.org

With reference to the Feature Synopsis
http://www.w3.org/TR/owl-features/ :

> differentIndividualFrom: Two individuals may be stated to be different from each other. For example, the individuals Frank and Deborah may be stated to be different from each other. From this, the reasoner can deduce that Frank and Deborah refer to two unique individuals. Thus, if the individuals Frank and Deborah are both values for a property that is stated to be functional (thus the property has at most one value), then there is a contradiction. Stating differences can be important in systems such as OWL (and RDF) that do not assume that individuals have one and only one name. For example, OWL with no additional information, will not deduce that Frank and Deborah refer to distinct individuals. 

Does this not lead to an explosion of properties in applications where
the majority of individuals do have unique names? I.e. for N individuals
we would require N(N-1)/2 differentIndividualFrom properties?


David Allsopp

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Received on Friday, 2 August 2002 06:05:09 GMT

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