- From: OWL <sysbot+tracker@w3.org>
- Date: Thu, 25 Oct 2007 04:42:44 +0000 (GMT)
- To: public-owl-wg@w3.org
ISSUE-22 (role-rule-sugar): Add sugar for rule (?x :hasSibling ?y) ^ :Male(?y) => (?x :hasBrother ?y) http://www.w3.org/2007/OWL/tracker/issues/ Raised by: Alan Ruttenberg On product: Reported by alanruttenberg, Oct 02, 2007 See thread http://lists.w3.org/Archives/Public/public-owl-dev/2007OctDec/0004.html example how in http://lists.w3.org/Archives/Public/public-owl-dev/2007OctDec/0015.html (R4) SubObjectPropertyOf(SubObjectPropertyChain(sibling manman) brother) (A1) SubClassOf( Man ObjectExistsSelf(manman) ) (A3) ObjectPropertyDomain( manman Man ) (A4) FunctionalObjectProperty( manman ) Delete comment Comment 1 by alanruttenberg, Oct 06, 2007 Ian Horrocks says: Now you have pointed out the basic trick, I wonder why the set of axioms for expressing this rule is so complex. In particular, why do we need it to be the case that manman(x,x) <=> Man(x) -- wouldn't it be enough that Man(x) => manman(x,x)? We could also do without reflexivity -- we could simply use an existential restriction to force the existence of *some* manman relation and then use (sibling manman InverseObjectProperty(manman)) as the role chain implying brother. This would give: SubClassOf(Man ObjectExists(manman Thing)) SubObjectPropertyOf(SubObjectPropertyChain(sibling manman InverseObjectProperty(manman)) brother)
Received on Thursday, 25 October 2007 04:42:51 UTC