Re: question on rdfs:domain

On Feb 21, 2005, at 9:11 AM, Jeremy Carroll wrote:

> Bijan Parsia wrote:
> > Unless I've screwed it up due to fatigue :) But I don't think so
> > glancing back.
>
> I suspect you might need some sleep, but me too, ...

Heh.

> (hmmm you wrote before the weekend, me after, is work or play more 
> exhausting?)

Illness is the worse.

> isn't the RDF/XML fragment identical in triples to
>
> <owl:ObjectProperty rdf:ID="someProperty">
>      <rdfs:domain>
>        <owl:Class>
>          <owl:unionOf rdf:parseType="Collection">
>          </owl:unionOf>
>        </owl:Class>
>      </rdfs:domain>
> </owl:ObjectProperty>
>
> and hence in DL and represents a property with empty domain, i.e. an 
> empty property.

Yes you are write. I got tripped up because I forgot that syntactic 
equivalence.

To the original poster, this will probably be established by the 
transformation to triples table in the OWL Semantics and Abstract 
Syntax document.

However, the rest of what I said still seems sensible. There are many 
ways to make a property "inapplicable" either by restricting the domain 
or range (and with inverses, it pretty much doesn't matter which). Any 
which way, it ensures that there can be no (consistent) instantiation 
of the property in your KB.

Thanks to Jeremy for the correction.

Cheers,
Bijan Parsia.

Received on Monday, 21 February 2005 15:51:04 UTC