RE: What do the ontologists want

pat hayes wrote,
> As far as I understand what is meant by 'reification' in this 
> context, I see only a very limited utility, basically things like 
> tagging a string/expression with information about its source, 
> time-stamping and so on.

I think this is a little hasty. Quotation and 'reification', in your
scare quote sense of abstract syntax rather than propositional
content, have some very important roles to play. To borrow some
examples from Tarski and Davidson,

  "Snow is white" is-true-in-english iff snow is white
  "Schnee ist weiss" is-true-in-german iff snow is white

or better,

  "Snow is white" means-in-english that snow is white
  "Schnee ist weiss" means-in-german that snow is white

The first example in each of these pairs baffles first year philosophy
undergraduates, but the second makes things somewhat clearer: where
the quoted expressions are drawn from an given object language the
respective truth and meaning predicates can be used to set up
correspondances target (I won't say meta- here) language. Fill this
out sufficiently and toss in some syntactic structure on the quoted
side and you have a translation scheme for the object language to the
target language.

Bearing in mind that a lot of the stuff that people will be wanting
to do with RDF is set up mappings between local and non-local
vocabularies this strikes me as being of more that 'very limited
utility'.

But don't take my word for it: cp. Tarski, "The concept of truth in
formal languages".

> Most of the proposed uses of reification in the RDF literature seem 
> to me to be based on confusion, and many of them - most notably, the 
> idea that propositional structure and quantification can be provided 
> by reification - are just nonsense.

This I agree with wholeheartedly.

Cheers,


Miles

-- 
Miles Sabin                                     InterX
Internet Systems Architect                      27 Great West Road
+44 (0)20 8817 4030                             Middx, TW8 9AS, UK
msabin@interx.com                               http://www.interx.com/

Received on Tuesday, 15 May 2001 16:15:10 UTC