- From: Dan Connolly <connolly@w3.org>
- Date: Fri, 18 Apr 2008 17:31:38 -0500
- To: public-cwm-talk@w3.org, Jeff Thompson <jeff@thefirst.org>
> However, bob already owns Fluffy who is a Cat, but cwm seems to ignore this and asserts that > he owns another Cat: > :bob a :CatLover; :owns :fluffy, [a :Cat]. Well, cwm isn't saying whether [a :Cat] is the same cat as :fluffy or not. > I ask because cwm will match existing existentials in the antecedent, so shouldn't > it also match them in the consequent, and just leave it as bob owns Fluffy without > adding another assertion? Perhaps... cwm does some redundancy checking, but it's not smart enough to realize that :bob :owns [a :Cat] is redundant w.r.t. :bob :owns :fluffy. :fluffy a :Cat. The problem of figuring out which part of the conclusion is redundant is pretty hard. It's called the subgraph isomorphism problem, I gather. See also discussion of "leaning". http://www.w3.org/TR/2004/REC-rdf-mt-20040210/#deflean http://www.w3.org/2001/sw/DataAccess/issues#rdfSemantics -- Dan Connolly, W3C http://www.w3.org/People/Connolly/ gpg D3C2 887B 0F92 6005 C541 0875 0F91 96DE 6E52 C29E
Received on Friday, 18 April 2008 22:32:08 UTC