- From: Miles Sabin <MSabin@interx.com>
- Date: Tue, 15 May 2001 21:14:22 +0100
- To: pat hayes <phayes@ai.uwf.edu>, Uche Ogbuji <uche.ogbuji@fourthought.com>
- Cc: Jonathan Borden <jborden@mediaone.net>, www-rdf-logic@w3.org
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