- From: Dave Reynolds <der@hplb.hpl.hp.com>
- Date: Fri, 24 Mar 2006 11:50:55 +0000
- To: Dan Brickley <danbri@danbri.org>
- CC: semantic-web@w3.org
Dan Brickley wrote: > It's also worth keeping an eye on the W3C Rule Interchange Format > Working Group, see http://www.w3.org/2005/rules/ -> > http://www.w3.org/2005/rules/wg.html > > They have a use cases and requirements draft out (which I've only > just noticed by accident, but which appears to be dated today!), > http://www.w3.org/2005/rules/wg/ucr/draft-20060323.html > > A rule language could be rich enough to handle quoting more robustly > than RDF reification. But I wouldn't bet on it :) I'd be interested to > hear from WG members on this point. I seem to recall that some of the original submitted usecases for RIF mentioned reification[*] but more in the sense of making things like policy rules first class objects in the domain, rather than in the sense of RDF provenance tracking. I personally wouldn't expect RIF to be the right place to re-examine RDF reification. The charter does include mention of scoped inference (such as scoped negation as failure). So it's possible that might mean a rule could ask whether some fact was stated in a given scope (e.g. at a particular web data source) - but we already have that capability with SPARQL, as you pointed out. Note that the RIF charter does not actually call for a semantic web rule language but for a framework for interchange of rules between different systems. I guess someone could make an argument that CWM has a quoting mechanism with its nested formulae and request that RIF should be capable of interchanging CWM rules with other potentially-compatible-rule-languages :-) [BTW I don't think it's quite fair to describe RDF reification as not "robust" - it does just what it says on the packet. The message from Pat that Frank pointed to makes the issues clear and I'm not sure there is a better solution. If you want de dicto then you can always use literals/XMLLiterals or reference back to the raw document (as your SPARQL solution is doing). For a framework for describing chains of deductions, which seems to be what your example is really asking for, then you might find Inference Web useful: http://iw.stanford.edu/ That includes an (OWL) ontology for exchanging proof chains. ] Dave [*] It amuses me that the Mozilla spell checker suggests "deification" as a correction for "reification".
Received on Friday, 24 March 2006 12:13:46 UTC