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Re: SEM: comprehensive entailments without dark triples

From: Dan Connolly <connolly@w3.org>
Date: 22 Apr 2002 10:58:17 -0500
To: "Peter F. "Patel-Schneider <pfps@research.bell-labs.com>
Cc: Jeremy Carroll <jjc@hplb.hpl.hp.com>, www-webont-wg@w3.org
Message-Id: <1019491098.4817.460.camel@dirk>
On Mon, 2002-04-22 at 10:41, Peter F. Patel-Schneider wrote:
> The problem with these comprehension principles is that they do not
> generate non-tree structures.  Therefore classes that are not in the form
> of trees (yes, this is rather vague, but my previous message gives one
> example) will not be consequences.

I'm having a hard time seeing this as a problem.

This is the example from your message of
22 Apr 2002 11:29:50 -0400; that's the one you refer to, yes?

     John rdf:type Person .
     Bill rdf:type Person .
     John child Bill .
entailing
     John rdf:type _:1 .
     _:1 rdf:type daml:Restriction .
     _:1 rdf:onProperty child .
     _:1 rdf:hasClass :_1 .


I can't understand it well enough to see why I would want
it to be the case.

By way of trying to relate this to some use case
or requirement, here's an attempt at a sort of
natural-language translation:

  If John has a child, then John is in the class
  of things that have children that are in this
  class I'm talking about.

It just looks like gobbledygook.

It seems to me we can meet our requirements and
users' expectations without this entialment holding.

Am I missing something?


-- 
Dan Connolly, W3C http://www.w3.org/People/Connolly/
Received on Monday, 22 April 2002 11:59:23 GMT

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