- From: Richard H. McCullough <rhm@cdepot.net>
- Date: Tue, 19 Nov 2002 11:45:49 -0800
- To: <rinke@lri.jur.uva.nl>, <www-rdf-interest@w3.org>
- Message-ID: <000d01c29004$430ba220$bd7ba8c0@rhm8200>
Whoops! I got a little careless there.
The RDF axiom
rdf:type(?x,?y) iff ?y(?x)
translates to
<?x> <rdf:type> <?y> iff <?x> <rdfs:subClassOf> <?y> or <?x> <rhm:individualOf> <?y>
Note: rhm:individualOf is my proposal for an additional property owl:individualOf.
The RDFS axiom
?y(?x) implies rdfs:Class(?y)
translates to
<?x> <rdfs:subClassOf> <?y> or <?x> <rhm:individualOf> <?y> implies <?y> <rdfs:subClassOf> <rdfs:Class>
So, I agree with you that "?y is a Class". I think that
<?y> <rdfs:subClassOf> <rdfs:Class>
is the "correct" RDFS way to say "?y is a Class". I also think it's wrong; I think it should be
<?y> <rdfs:subClassOf> <rdfs:Resource>
because "Resource" alias "Thing" alias "existent" is the concept which subsumes all other concepts.
I hope Pat Hayes will step in and correct me if I am misinterpreting his rdf-mt document.
============
Dick McCullough
knowledge := man do identify od existent done
knowledge haspart list of proposition
----- Original Message -----
From: Rinke Hoekstra
To: 'Richard H. McCullough' ; www-rdf-interest@w3.org
Sent: Tuesday, November 19, 2002 10:34 AM
Subject: RE: RDF vocabulary definitions
Richard,
Although I am most certainly not an expert, I have some remarks below.
-----Original Message-----
The rdf-mt document http://www.w3.org/TR/2002/WD-rdf-mt-20021112/
says in Appendix A, "RDF Axioms":
rdf:type(?x,?y) iff ?y(?x)
The triple translation is
<?x> <rdf:type> <?y> iff <?x> <rdfs:subClassOf> <?y>
I do not agree, the appendix under “RDFS Axioms” states (slightly rewritten to avoid confusion):
?y(?x) implies rdfs:Class(?y)
Which means that ?y is a class if ?x is of the type ?y. This shows that ?y(?x) does not mean that ?x is a subclass of ?y at all. Why would we need a distinction between rdf:type and rdfs:subClassOf if they were equivalent?
Regards,
Rinke Hoekstra
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Received on Tuesday, 19 November 2002 14:45:51 UTC