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Re: Reification: naive question

From: Wolfgang Nejdl <nejdl@kbs.uni-hannover.de>
Date: Fri, 08 Feb 2002 00:15:48 +0100
Message-Id: <200202072315.g17NFmf02717@mahler.kbs.uni-hannover.de>
To: "Seth Russell" <seth@robustai.net>
cc: "Enrico Franconi" <franconi@cs.man.ac.uk>, www-rdf-logic@w3.org
> From: "Enrico Franconi" <franconi@cs.man.ac.uk>
> 
> > Sorry if this question looks naive, or if you had on this already a
> > big discussion in the past (which is likely anyway).
> >
> > Suppose that a unique id is associated to each triple. This could be
> > either implicit (i.e., generated internally like OIDs in O-O data
> > models) or explicit (if you want to mention it later).
> >
> > The additional (explicit) ID serves as a reference in other triples
> > willing to state something on it (as a foreign key). I understand that
> > this is the spirit of reification.
> 
> > For the triples where the ID is implicit, the syntax wouldn't change,
> > and the semantics could be the standard MT already devised.
> >
> > If the current MT wants to ignore reification (as it correctly does),
> > then it should just ignore the presence of those additional IDs. This
> > makes a lot of sense since the semantics of reification is still
> > unclear, and a lot of work should be done. A future extension of the
> > MT (based supposedly on HOL) could then take IDs into account.
> >
> > This is more or less in the spirit of Nejdl's proposal.
> >
> > - do you have the feeling that this would solve all the problems (on
> >   expressiveness and on semantic clarity) of reification?  [please,
> >   note the naivete of the question :-)]
> >
> > - Would this be an impossible addition to the rdf standard syntax?
> 
> Actually there is the idAttr allowable on a property element .. see section
> D production 6.12 of the revised syntax:
> <http://www.w3.org/TR/2001/WD-rdf-syntax-grammar-20011218/#section-Grammar>
> But I'm not sure whether it is practical to used that for your purpose.
> 
> But isn't it better just to keep piling more and more restraints on a
> reified statement untill it can only be satisfied by one instance of the

Why should you do that? If you want to say something about a
statement, the easiest way would be to directly refer to it (using a
name / an ID / etc.)

Wolfgang

> triple?  See my example at the bottom of the following post:
> 
> http://lists.w3.org/Archives/Public/www-rdf-logic/2002Feb/0031.html
> 
> Seth Russell
> 


--
Prof. Dr. Wolfgang Nejdl              tel. +49 511 762-19710
Institut für Technische Informatik    fax. +49 511 762-19712
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Received on Thursday, 7 February 2002 18:18:58 GMT

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