Re: third version of semantics document

From: pat hayes <phayes@ai.uwf.edu>
Subject: Re: third version of semantics document
Date: Thu, 5 Sep 2002 23:14:09 -0700

> >As an indication of how things can go wrong in a complicated specification,
> 
> Well, amen to that.
> 
> >Pat's document is very close to implying that all RDFS classes and
> >properties are OWL objects.
> >
> >Why is this?
> >
> >First, the extension of the denotations of rdfs:subClassOf and
> >rdfs:subPropertyOf are transitive relations according to the RDFS 
> >model theory.
> >Second, a resource belongs to the class extension of the denotation of
> >owl:TransitiveProperty if its extension is transitive.
> 
> Yeh, that was a mistake. Should have been 'only if' not 'iff'. My 
> fingers tend to write 'iff' to mean 'corresponds roughly to' when my 
> mind is distracted; I am aware of this failing and usually check 
> drafts carefully before releasing them.
> 
> >Therefore, the denotations of rdfs:subClassOf and rdfs:subPropertyOf belong
> >to the class extension of the denotation of owl:TransitiveProperty.
> 
> At most, what should be in that class are the restrictions of 
> rdfs:subClassOf to owl:Class and similarly for properties.
> 
> Pat

Not so, as OWL classes are not OWL objects.

peter

Received on Friday, 6 September 2002 09:04:27 UTC