- From: Bijan Parsia <bparsia@cs.man.ac.uk>
- Date: Fri, 29 Aug 2008 10:49:37 +0100
- To: Alan Ruttenberg <alanruttenberg@gmail.com>
- Cc: W3C OWL Working Group <public-owl-wg@w3.org>, Boris Motik <boris.motik@comlab.ox.ac.uk>
First, these restrictions are perfectly global. That they *could be speced* with a grammar production is totally beside the point. I'm completely unmoved by worries that someone, somewhere might come along and complain that these restricitons aren't "really" global, especially on such weak tea as that possibility of inlineing that production. Second, it's much preferable to have the general restrictions on anonymous individuals grouped in one place, e.g.,: No axiom in Ax of the following form contains anonymous individuals: SameIndividual, DifferentIndividuals, NegativeObjectPropertyAssertion, and NegativeDataPropertyAssertion. A forest F over the anonymous individuals in Ax exists such that, for each axiom in Ax of the form PropertyAssertion( P a1 a2 ) with P an object property and a1 and a2 anonymous individuals, either a1 is a child of a2 in F or a2 is a child of a1 in F. This is much clearer than separating them. The second one is clearly global by any standard. It's helpful for OWL Full as well, since you just drop those constraints the way you drop the regularity constraints. Your profile/silent implementation worries just don't seem sensible. If there's a real concern then just munging the presentation of the syntax is like security by obscurity, a false assurance. People are, of necessity, going to implement various fragments and extensions and we shouldn't make it pointlessly harder for them or for people to figure out what they've done. Finally, this would cause me to rethink my grudging support for this semantics. Cheers, Bijan.
Received on Friday, 29 August 2008 09:47:11 UTC