- From: Wagner, G.R. <G.R.Wagner@tm.tue.nl>
- Date: Tue, 10 Sep 2002 20:27:23 +0200
- To: "'Tim Berners-Lee'" <timbl@w3.org>, Sandro Hawke <sandro@w3.org>
- Cc: www-rdf-rules@w3.org
> I think the concept of a difference between a rule and a > statement is a trap. Like the difference (argued to bits > on the list from time to time!) between entailment and > implication. The fact is that you can take > one logic in which something occurs as an axiom, expressed > as an entailment, and convert the same data into another > logic in which there is a general axiom for an implication > operator, and then the same information originally in an > axiom is expressed as a a ground fact using implication. Yes, this correspondence is generally provided by the "deduction theorem" which is either provable in a logic or it is used as the definition for introducing an implication connective. Notice that in a constructive logic approach (e.g., in intuitionistic logic) implication is defined on the basis of entailment and not as "material implication" by means of disjunction and negation. -Gerd http://tmitwww.tm.tue.nl/staff/gwagner/
Received on Tuesday, 10 September 2002 14:27:37 UTC