The definition of entailment in the Direct Semantics document

OWL WG,

I believe, after review of test case [WebOnt-Class-005], that the
definition of entailment [1] in the OWL 2 Direct Semantics document
differs from the definition used by the WebOnt WG.  The entailment
test case is repeated below.  In WebOnt, this was a negative
entailment test (i.e., O did not entail O').  I believe that with the
current definitions, it would be a positive entailment test.   If the
group agrees with this analysis, we can accept the change in
definition or tweak the Direct Semantics document to match the
previous (WebOnt) meaning.

O:
 ClassAssertion( owl:Thing x )

O':
 Declaration( Class( C ) )
 ClassAssertion( UnionOf( C ComplementOf( C ) ) x )

-- 
Mike Smith

Clark & Parsia

[1] http://www.w3.org/2007/OWL/wiki/Direct_Semantics#Inference_Problems
[WebOnt-Class-005]
http://km.aifb.uni-karlsruhe.de/projects/owltests/index.php/TestCase:WebOnt-Class-005

Received on Thursday, 15 January 2009 15:30:03 UTC