From the W3C: "The Rule Interchange Format (RIF) Working Group published three drafts today: RIF Basic Logic Dialect (RIF-BLD), RIF Framework for Logic Dialects (RIF-FLD) and RIF RDF and OWL Compatibility (RIF-RDF-OWL). These drafts help solidify the 'pure logic rules' branch of RIF, which is distinct from the 'production rules' branch (on which a Working Draft is expected within the next 6 months)." This takes me back to my predicate calculus days. Ugh. I can't say the W3C formulation makes things clearer (much less human readable) - and I can't say that I think the use of ^^ as a frequently used notation was well thought out.