W3C home > Mailing lists > Public > www-webont-wg@w3.org > August 2003

Re: minor typos in Test doc

From: Jos De_Roo <jos.deroo@agfa.com>
Date: Wed, 13 Aug 2003 11:28:18 +0200
To: "Sean Bechhofer <seanb" <seanb@cs.man.ac.uk>
Cc: connolly@w3.org, www-webont-wg@w3.org, jjc@hpl.hp.com
Message-ID: <OF5006EBF5.22D653BC-ONC1256D81.003274ED-C1256D81.0034079B@agfa.be>


[Sean's explanation of
http://www.w3.org/2002/03owlt/description-logic/inconsistent107.rdf]

> The role hierarchy is a bit of a red herring here, as is the definition
> of a.

I never clearly understood what "red herring" meant; now I got it ;-)

> The definition of Unsatisfiable says that anything that's an instance of
> Unsatisfiable has to have at least 1 r, has to be related to a c via r
and
> has to be related to a d via r. It must also be related to no more than
> one thing via r (the complement of [minCard 2 r] is [maxCard 1 r]). But
> this leads to a contradiction as c and d are disjoint.

OK - my understanding of owl:someValuesFrom was wrong
I thought that the intersectionOf
  restriction(a:r someValuesFrom a:d)
  restriction(a:r someValuesFrom a:c)
wasn't that strongly constrained ie that it has
some members related to a c via r and some other
members related to a d via r but I guess that's
what you call a unionOf isn't it?


> Does that help?

Quite a lot, thanks Sean.


--
Jos De Roo, AGFA http://www.agfa.com/w3c/jdroo/
Received on Wednesday, 13 August 2003 05:29:01 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:58:01 GMT