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Re: Treating a class as both an individual and a class?

From: Nikita Ogievetsky <nogievet@cogx.com>
Date: Mon, 10 Mar 2003 08:38:06 -0800
To: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>
Cc: <costello@mitre.org>, <www-rdf-logic@w3.org>
Message-ID: <OE52RxNKiA8RS7ptQvf000204b7@hotmail.com>

Peter,

Oops... again a typo (what is going on? :-))! I meant to say:

<owl:Class rdf:ID="CityOnARiver">
   <rdfs:subClassOf rdf:resource="#City">
   <rdfs:subClassOf>
     <owl:Restriction>
       <owl:onProperty rdf:resource="hasFeature" />
       <owl:someValuesFrom rdf:resource="http://geodesy.org#River"/>
     </owl:Restriction>
   </rdfs:subClassOf>
</owl:Class>

> In OWL you could do other interesting things then
> 
> 1/ <CityOnARiver rdf:ID="Davenport">
>          ....
>    </CityOnARiver>
> 
>    makes Davenport a city that has a river as a feature (without saying
>    which one it is).
> 
> 2/ <http://geodesy.org#River" rdf:ID="YYYRiver" />
> 
>    <City rdf:ID="Davenport">
>          <hasFeature rdf:resource="#YYYRiver" />
>    </City>
> 
>    makes Davenport a city on the YYYRiver and also an instance of
>    CityOnARiver (without mentioning CityOnARiver explicitly).
> 

Interesting. Do you mean that "2/" is semantically equivalent to 
<CityOnARiver rdf:ID="Davenport">
    <hasFeature rdf:resource="#YYYRiver" />
</CityOnARiver>
?

In other words, "is-a CityOnARiver" assertion will be inferred from
"hasFeature YYYRiver",  "is-a City"?
This is very becoming but also looks rather dangerous.
I wonder if tools can really support this.

--Nikita
Received on Monday, 10 March 2003 15:10:00 GMT

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