- From: Jan Grant <Jan.Grant@bristol.ac.uk>
- Date: Fri, 30 Mar 2001 12:03:21 +0100 (BST)
- To: David Allsopp <dallsopp@signal.dera.gov.uk>
- cc: www-rdf-logic <www-rdf-logic@w3.org>
On Fri, 30 Mar 2001, David Allsopp wrote: > > Dear all, > > I hope you'll forgive a (probably very naive) question: In the DAML+OIL > walkthrough, we have the following example of a cardinality restriction > (plus another minCardinality restriction). > > <rdfs:subClassOf> > <daml:Restriction daml:cardinality="1"> > <daml:onProperty rdf:resource="#hasFather"/> > </daml:Restriction> > </rdfs:subClassOf> > <rdfs:subClassOf> > <daml:Restriction> > <daml:onProperty rdf:resource="#shoesize"/> > <daml:minCardinality>1</daml:minCardinality> > </daml:Restriction> > </rdfs:subClassOf> > > "This requires that any person must have exactly 1 father and at least > one shoe size. Again, this is done by first using a Restriction to > define an anonymous class (in this case the class of all things that > have exactly one father), and then demanding that Person is a subClassOf > this anonymous > class (i.e., demanding that every Person satisfies this Restriction)." I can't help feeling a little worried by these examples. Yes, I know they're "only" examples. But the model of the world they present is broken - will DAML be good for describing the real world or just mathematical arenas and EDI? Is it even wise to try the former - or should the examples be rewritten to be less contentious? jan "Human beings without feet are people too" grant PS. According to Tuco, Blondie doesn't satisfy the first constraint either :-) -- jan grant, ILRT, University of Bristol. http://www.ilrt.bris.ac.uk/ Tel +44(0)117 9287163 Fax +44 (0)117 9287112 RFC822 jan.grant@bris.ac.uk Usenet: The separation of content AND presentation - simultaneously.
Received on Friday, 30 March 2001 06:04:00 UTC