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Re: reification test case

From: Seth Russell <seth@robustai.net>
Date: Wed, 6 Feb 2002 12:53:21 -0800
Message-ID: <010701c1af50$502c2780$657ba8c0@c1457248a.sttls1.wa.home.com>
To: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>
Cc: <www-rdf-logic@w3.org>
From: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>

> > > > > > <rdf:description>
> > > > > > <rdf:type>:Statement</rdf:type>
> > > > > > <rdf:subject>:Gore</rdf:subject>
> > > > > > <rdf:predicate>:wonThe</rdf:predicate>
> > > > > > <log:truthValue>False</log:truthValue>
> > > > > > </rdf:description>
> > > > > >
> > > > > > which holds for all such statings.
> > > > > >
> > > > > > But I could also write:
> > > > > >
> > > > > > <rdf:description>
> > > > > > <rdf:type>:Statement</rdf:type>
> > > > > > <rdf:subject>:Gore</rdf:subject>
> > > > > > <rdf:predicate>:wonThe</rdf:predicate>
> > > > > > <dc:author>:Seth</dc:author>
> > > > > > <log:truthValue>False</log:truthValue>
> > > > > > </rdf:description>
> > > > > >
> > > > > > which holds for a smaller collection of statings.

> HUH?  How can this be?  The resources above are *resources*, i.e., single
> elements of the domain.

The word 'single' is what we are arguing about.  Certainly Bnodes do not
necessarily refer to a single element of the domain, and nodes of rdf:type
rdf:Statement are certainly Bnodes.

>There is nothing that I can find anywhere in RDF
> or RDFS that indicates that any particular resource aside from collections
> refers to a set of anything.

Agree, I should have said subclass.

> How can the first resource above refer in RDF (or RDFS) to ``all statings
> with those three properties which are False''?  There is something that I
> do *not* understand in your claim above.  Please indicate how you have
come
> by this understanding of RDF(S).

If statings are represented in RDF by Bnodes (and I believe they are), then
they are just like a KIF  expression

((exists ?x)
     (and (rdf:type :Statement) (rdf:subject :S) (rdf:predicate :P)
(rdf:object :O) (.....)  ))

substitute whatever extra qualifications you want for the (...) .

> The point is that you seem to be aiming toward the view that there is some
> difference in essence between the RDF meanings of the two resources just
> above.  The two things above are just resources, nothing more, nothing
> less.  They are the subject of several RDF statements (three for the first
> and five for the second), one of which is given a slight bit of extra
> meaning by RDFS, but nothing to indicate that there is a type/token
> distinction between them.

Could you educate me on the meaning of this term type/token distinction ?

Seth Russell
Received on Wednesday, 6 February 2002 15:57:07 GMT

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