W3C home > Mailing lists > Public > www-webont-wg@w3.org > June 2002

Re: update to the compliance document

From: Jim Hendler <hendler@cs.umd.edu>
Date: Wed, 5 Jun 2002 18:39:29 -0400
Message-Id: <p05111708b92443234d9f@[]>
To: Frank van Harmelen <Frank.van.Harmelen@cs.vu.nl>, Enrico Motta <e.motta@open.ac.uk>
Cc: Deborah McGuinness <dlm@ksl.stanford.edu>, Webont <www-webont-wg@w3.org>

At 12:29 AM +0200 6/6/02, Frank van Harmelen wrote:
>Enrico Motta wrote:
>>  Deborah,
>>  Just one minor comment.  The document does not explicitly say whether
>>  subclassOf hierarchies can have cycles (like daml+oil) or not (like
>>  rdfs).  Because subclassOf properties are listed under Rdfs features,
>>  one would think that no cycles are allowed, while the presence of
>>  sameClassAs in the language leads one to think that cycles are OK.
>Even RDFS now allows cycles in the class hierarchy.
>We might point out in our own document that as a result,
>sameClassAs is simply syntactic sugar (but: useful syntactic sugar)
>for something that could already be done without it (even in RDF Schema).

Frank - not sure if this is true in a multi-ontology setting

jim:foo owl:sameClassAs frank:bar.

can be used in cases where the only way to create the cycle would be 
for me to call you up and ask you to put a pointer to my subclass in 
your document.  So I think some of these things (the "equivalentTo 
family") are important for the cross ontology requirement as well as 
within ontologies.

Professor James Hendler				  hendler@cs.umd.edu
Director, Semantic Web and Agent Technologies	  301-405-2696
Maryland Information and Network Dynamics Lab.	  301-405-6707 (Fax)
Univ of Maryland, College Park, MD 20742	  240-731-3822 (Cell)
Received on Wednesday, 5 June 2002 18:39:49 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 21:56:44 UTC