- From: Pat Hayes <phayes@ai.uwf.edu>
- Date: Tue, 19 Feb 2002 15:40:08 -0600
- To: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>
- Cc: webont <www-webont-wg@w3.org>
>Here is my reply to Pat's comments that the restriction I presented does >not indicate a paradox in the same-syntax extension layering of OWL on top >of RDF. > > > > > The Same-Syntax Extension Paradox > > >Here is a more-detailed derivation of the paradox that I see when producing >same-syntax extensions of RDF. > >There are two roads to a paradox. One of these roads uses features that >are not in DAML+OIL, but exist in some DLs. The other, longer, more >complicated road uses only features that are in DAML+OIL. > >The basic methodology here is to extract the properties of a same-syntax >extension building on the new RDF model theory. This is mostly done by >determining what entailments (or derivations, if you like) are needed and >seeing what constraints this places on OWL (or OWL+, a more-powerful >version of OWL) interpretations. I've tried to stay as close to the >terminology in the new RDF model theory as possible. > >The summary of all this is that if you want to be a same-syntax extension >of the RDF model theory and you have >a) rdf:type as a property; >b) defined classes, like DAML+OIL restrictions; >c) some sort of complement or negation; and >d) self reference >then you have a semantic paradox. Before I invest a lot of time in reading through the rest of this, could you clarify what you mean here by 'self-reference'? I ask because in any sense of that term that I know of, neither RDF nor DAML is self-referential, and previous discussion on this thread has confused self-reference with nonwellfoundedness. Pat -- --------------------------------------------------------------------- IHMC (850)434 8903 home 40 South Alcaniz St. (850)202 4416 office Pensacola, FL 32501 (850)202 4440 fax phayes@ai.uwf.edu http://www.coginst.uwf.edu/~phayes
Received on Tuesday, 19 February 2002 16:40:12 UTC