Re: OWL species and subproperties of rdfs:label

Dave Reynolds wrote:

> Bernard Vatant wrote:
> 
>> So would you recommend to avoid such declarations altogether? And in
>> this case, what do I do about Tim's request for such declarations to be
>> present in order to make Tabulator happy?
> 
> Fundamentally by extending rdfs:label you are in OWL/full, I don't think
>  there is a way round that. Personally many things I do with OWL end up 
> in OWL/full and generally I don't find that to be a fatal problem.

Another question would be, if it were an option to change this restriction
in some future version of OWL (perhaps in OWL 2.0), so that it would then
also be possible to create subproperties of annotation properties in OWL/DL
or OWL/Lite.

OWL in fact already contains an example for a subproperty of an
owl:AnnotationProperty, which itself is an owl:AnnotationProperty:

   rdfs:isDefinedBy rdfs:subPropertyOf rdfs:seeAlso .

So, this axiom between two annotation properties is always there,
without putting my ontologies automatically into OWL/Full.
Now, this axiom actually is a /built-in/. The next question would
therefore be: What are the dangers in letting people freely define their own
owl:AnnotationPropertyS as subproperties of other owl:AnnotationPropertyS
in OWL/DL? Are there semantical issues? Are there computational (like
decidability or complexity) issues?

The spec, regrettably, does not seam to help here any further. AFAICS it
simply categorically forbids the use of sub-Annotationproperties:

   <http://www.w3.org/TR/owl-ref/#Annotations>

   "Annotation properties must not be used in property axioms.
   Thus, in OWL DL one cannot define subproperties [...]
   for annotation properties."

But I did not find any reason there, /why/ this is forbidden.

Any hints or comments?

Cheers,
Michael

Received on Tuesday, 9 January 2007 12:33:59 UTC