- From: Michael Schneider <schneid@fzi.de>
- Date: Tue, 8 Apr 2008 10:16:05 +0200
- To: <public-owl-wg@w3.org>
- Cc: <jjc@hpl.hp.com>
- Message-ID: <0EF30CAA69519C4CB91D01481AEA06A0803D36@judith.fzi.de>
>ISSUE-113 (OWL-R nonentailments): Some OWL-R nonentailments >are OWL-Full entailments > >http://www.w3.org/2007/OWL/tracker/issues/ > >Raised by: Jeremy Carroll >On product: > > >Is a tool that provides all OWL-R rules and some others that >are licensed by OWL Full, still OWL-R conformant. > >i.e. > >if O1 entails O2 in OWL Full, but O2 does not follow using the >OWL-R ruleset applied to O1 then is an OWL-R conformant tool >permitted to find O2? I would say "no". Let's assume that O1 is consistent both under OWL-R and OWL-Full semantics. And let's further assume that it is possible in OWL-R to specify an NO2, which contradicts O2. An example might be: O2 := { u owl:differentFrom w } NO2 := { u owl:sameAs w } Then the combined ontology O* := O1+NO2 will still be an R-consistent ontology. But O* will be Full-inconsistent, since the additional Full-entailment O2 contradicts NO2. Hence, with an "R+"-reasoner, which produces additional OWL R-non-entailments as inferences, it might become possible to create an ontology, which is R-consistent, but for which the "R+"-reasoner would tell me that this ontology is inconsistent. This is not what I would call "R-conformant behaviour". Generally, if a reasoner for a language L produces inferences for which there are no L-entailments, then this is what I know as "non-sound" L-reasoning. So I would opt to say that an "OWL R-conformant" reasoner *MUST NOT* infer non-entailments of OWL R. Cheers, Michael -- Dipl.-Inform. Michael Schneider FZI Forschungszentrum Informatik Karlsruhe Abtl. Information Process Engineering (IPE) Tel : +49-721-9654-726 Fax : +49-721-9654-727 Email: Michael.Schneider@fzi.de Web : http://www.fzi.de/ipe/eng/mitarbeiter.php?id=555 FZI Forschungszentrum Informatik an der Universität Karlsruhe Haid-und-Neu-Str. 10-14, D-76131 Karlsruhe Tel.: +49-721-9654-0, Fax: +49-721-9654-959 Stiftung des bürgerlichen Rechts Az: 14-0563.1 Regierungspräsidium Karlsruhe Vorstand: Rüdiger Dillmann, Michael Flor, Jivka Ovtcharova, Rudi Studer Vorsitzender des Kuratoriums: Ministerialdirigent Günther Leßnerkraus
Received on Tuesday, 8 April 2008 08:16:43 UTC