- From: Ian Horrocks <Ian.Horrocks@comlab.ox.ac.uk>
- Date: Tue, 23 Oct 2007 11:49:40 +0100
- To: Jeremy Carroll <jjc@hpl.hp.com>
- Cc: public-owl-wg@w3.org
The motivation for properties such as subObjectPropertyOf is not related to punning. The idea is to facilitate parsing/species validation by enforcing strong typing. For example, it is illegal in OWL DL for a datatype property to be a subProperty of an object property, but when parsing a <P subPropertyOf S> triple, the types of P and S may not be known. As a result, not only will a decision on the species of the ontology need to be postponed, but it becomes dependent on a (relatively) complex and non-local condition, i.e., that P and S are either both datatype properties or both object properties. Ian On 23 Oct 2007, at 11:22, Jeremy Carroll wrote: > > > I think Jim's example about subObjectPropertyOf is compelling. > > In essence, I don't think we can publish a meaningful and helpful > RDF Mapping document until we have decided whether or not we accept > the 'punning' design in the member submission. > > I think this is one of the features of OWL 1.1 that causes the > greatest unease with the HP developers. As I understand the design, > language terms like subObjectPropertyOf are largely motivated by > the punning design. > > A further possible motivation is that in OWL 1.0, at I think mainly > my request, one design choice is that the triples version of OWL DL > is strongly typed, in the sense that (nearly) every URI and blank > node is required to have an rdf:type triple. Many of the required > type declarations are unnecessary, and it may be a better design to > allow unnecessary ones to be omitted. However, I think that the > explosion of terms in the member of submission is unfortuante, and > should be avoided. > > Jeremy > > > >
Received on Tuesday, 23 October 2007 10:49:49 UTC