Re: equivalentTo / sameClassAs / sameIndividualAs puzzle

From: Dan Brickley (
Date: 07/09/01

On Mon, 9 Jul 2001, Jeff Heflin wrote:

> Ian Horrocks wrote:
> > 
> > On July 7, Dan Brickley writes:
> > >
> > > I was concerned mostly with the classes case as I'm thinking about the
> > > subClassOf cycles issue. Reading on, same goes for samePropertyAs,
> > > sameIndividualAs; it seems equivalentTo is the odd one out, by talking
> > > about 'terms'.
> > 
> > You are reading more into the use of "terms" than was intended. It is
> > just an attempt to be vague/general w.r.t. the kinds of thing that are
> > being stated to be equivalent.
> > 
> I think the definition for equivalentTo should say that "X is an
> equivalent resource to Y," where resource is as defined in RDF. Since
> RDF resources can be classes, properties or anything else given a URI,
> this is compatible with the various subproperties of equivalentTo.
> sameIndividualAs is different from equivalentTo because the set of DAML
> individuals do not include classes or properties.

Aha! That's it. From reading the spec, it wasn't entirely clear to me
what DAML+OIL terms individuals. The schema definition suggests its a
synonym for 'thing':

	<Property rdf:ID="sameIndividualAs">
	for sameIndividualAs(a, b), read a is the same individual as b.
	<rdfs:subPropertyOf rdf:resource="#equivalentTo"/>
	<rdfs:domain rdf:resource="#Thing"/>
	<rdfs:range rdf:resource="#Thing"/>

Could someone explain to me which things precisely are considered
individuals? I gather properties and classes are out of the
picture. Any others? 



This archive was generated by hypermail 2.1.4 : 04/02/02 EST