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Re: A use case for anon nodes - action from telecon

From: Dan Brickley <danbri@w3.org>
Date: Fri, 20 Jul 2001 12:10:02 -0400 (EDT)
To: Graham Klyne <Graham.Klyne@Baltimore.com>
cc: Brian McBride <bwm@hplb.hpl.hp.com>, rdf core <w3c-rdfcore-wg@w3.org>
Message-ID: <Pine.LNX.4.30.0107201150360.30552-100000@tux.w3.org>
On Fri, 20 Jul 2001, Graham Klyne wrote:

> At 09:40 AM 7/20/01 -0400, Dan Brickley wrote:
> >I think part of the problem here is our natural tendency to take a
> >commonsense reading of what FOL "there exists" means, ie. reading
> >existential quantifier as taking about some form of "existence in the
> >world". If we try to take a strong reading of "there exists" we'll be
> >bouncing into a whole family of (what I understand to be) fairly well
> >known puzzles: how do we talk about pictures that depict Unicorns,
> >future events that may not come to pass etc.
>
> Dan,
>
> I think you've touched an important point here.  After I posted my
> comments, I also thought about Unicorns.  I think this is leading to the
> need for some kind of "reference without assertion" -- reification, or
> whatever.
>
> However, I do believe that "there exists" in logic does actually mean that
> something satisfying the associated description does indeed exist.  Without
> this, much of the maths I learned would collapse.

Just to clarify my position on this: I'm quite happy claiming that FOL's
"there exists" captures the technical meaning of the RDF "anonymous
resource" construct. So whenever I'm seen muttering about unicorns or
scratching my chin about the meaning of "there exists", I'm not casting
doubt on either (i) the reading of anonymous resources as "there
exists", (ii) the utility of the FOL machinery. The "technology and
society" problem of relating FOL statements to social/legal claims about
the world is a separate problem to clarifying the technical meaning of
"anonymous resources" in RDF. I believe the social/legal problem of "what
exactly am I asserting when I use RDF anoynmous resources in my RDF/XML
documents" can be reduced to the better understood (and non-Spec
related) "what am I asserting when I use 'there exists' in FOL".

--danbri
Received on Friday, 20 July 2001 12:11:29 EDT

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