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Re: ISSUE 5.18 Unique Names Assumption Support in OWL

From: Jos De_Roo <jos.deroo.jd@belgium.agfa.com>
Date: Thu, 24 Oct 2002 17:28:22 +0200
To: pfps@research.bell-labs.com
Cc: www-webont-wg@w3.org
Message-ID: <OF0D4CA346.B5A43081-ONC1256C5C.00541EA4-C1256C5C.00550006@agfa.be>


[...]

> > That is achieved with an inference rule such as
> > http://www.agfa.com/w3c/euler/owl-rules#rule10d1
> > which implies the ?x owl:differentIndividualFrom ?y
> > (instead of giving an order of faculty(n) facts).
>
> Unfortunately this rule won't (or, at least, shouldn't) do anything.  It
> says that if x /= y then x and y are different individuals.  Of course,
the
> whole problem is determining whether x is indeed not equal to y.  The
rule
> also appears to be doing something illegal with URI references in its use
of
> log:racine.

it indeed looks into URI references
for the rest I think the rule is OK
w.r.t. http://www.w3.org/2000/10/swap/log

> On looking at http://www.w3.org/2000/10/swap/log.n3 I realize that the
> intended meanings of the resources in the log: namespace are inherently
> broken.  For example, log:notEqualTo works on the identifier (URI
> (reference)) of its arguments, something completely outside the bounds of
> standard logic.
>
> This brings up a serious problem with the descriptions of CWM.  Sean
Palmer
> states that CWM is, in some sense, a forward chaining first-order
predicate
> logic inference engine.   However, if CWM is a reasoner over some logic,
> then the logic is a highly unusual intensional logic, and not any
standard
> first-order logic.

there are indeed intensional aspects here
(we have another one for (<uriP> ...) log:implies <uriC>
which does dereferencing)

-- ,
Jos De Roo, AGFA http://www.agfa.com/w3c/jdroo/
Received on Thursday, 24 October 2002 11:28:58 GMT

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