- From: Mike Smith <msmith@clarkparsia.com>
- Date: Wed, 18 Feb 2009 09:33:22 -0500
- To: W3C OWL Working Group <public-owl-wg@w3.org>
On Mon, Feb 16, 2009 at 16:58, Mike Smith <msmith@clarkparsia.com> wrote: > [Response for LC Comment 14] > The definition of ontology entailment in the OWL 2 Direct Semantics > document [1] is consistent with, and nearly identical to, the > definition of entailment presented in the OWL Direct Model-Theoretic > Semantics [2]. The definition of entailment used in the original RDF > Compatible Semantics [3] and the updated OWL 2 RDF Based Semantics [4] > differs from the definition used in in Direct Semantics documents. > Your comment highlights the difference between the Direct and RDF > based semantics, not a difference between OWL and OWL 2. Unfortunately, a more careful reading of OWL 1 docs show that the statements above are incorrect. Entailment in OWL 1 is defined in terms of interpretations satisfying ontologies. [2] places the following constraint on such satisfaction, which is not present in OWL 2. "each URI reference in O used as a class ID (datatype ID, individual ID, data-valued property ID, individual-valued property ID, annotation property ID, annotation ID, ontology ID) belongs to VC (VD, VI, VDP, VIP, VAP, VO, respectively); " I will modify the response, along the lines of -- yes it is a change from OWL 1, but one that permits an empty ontology to entail tautologies and is a good thing. -- Mike Smith Clark & Parsia > [1] http://www.w3.org/2007/OWL/wiki/Direct_Semantics#Inference_Problems > [2] http://www.w3.org/TR/owl-semantics/direct.html > [3] http://www.w3.org/TR/owl-semantics/rdfs.html > [4] http://www.w3.org/2007/OWL/wiki/RDF-Based_Semantics#Satisfaction.2C_Consistency_and_Entailment > [5] http://www.w3.org/2002/03owlt/Class/Manifest005#test
Received on Wednesday, 18 February 2009 14:34:03 UTC