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Re: matching existing existentials in the consequent.

From: Jeff Thompson <jeff@thefirst.org>
Date: Sun, 20 Apr 2008 00:17:28 -0700
Message-ID: <480AEE08.8020008@thefirst.org>
To: public-cwm-talk@w3.org

Dan Connolly wrote:
 >> 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.

I must beg to differ, because cwm is smart enough to realize this in the antecedent.
For example, the following matches with {:bob :owns :fluffy} as expected:
bob owns fluffy.
fluffy a Cat.
{?x owns [a Cat]} => {?x a CatOwner}.

 > The problem of figuring out which part of the conclusion is
 > redundant is pretty hard. It's called the subgraph isomorphism
 > problem, I gather.

Am I mistaken?  It seems that cwm can find the subgraph isomorphism in the antecedent.
Received on Sunday, 20 April 2008 07:18:02 GMT

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