- From: Graham Klyne <Graham.Klyne@Baltimore.com>
- Date: Fri, 20 Jul 2001 14:52:21 +0100
- To: Dan Brickley <danbri@w3.org>
- Cc: Brian McBride <bwm@hplb.hpl.hp.com>, rdf core <w3c-rdfcore-wg@w3.org>
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.
#g
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Graham Klyne                    Baltimore Technologies
Strategic Research              Content Security Group
<Graham.Klyne@Baltimore.com>    <http://www.mimesweeper.com>
                                 <http://www.baltimore.com>
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Received on Friday, 20 July 2001 09:54:07 UTC