- From: Michael Kifer <kifer@cs.sunysb.edu>
- Date: Thu, 12 Jan 2006 11:06:52 -0500
- To: "Gerd Wagner" <wagnerg@tu-cottbus.de>
- Cc: "'Enrico Franconi'" <franconi@inf.unibz.it>, "'Jos de Bruijn'" <jos.debruijn@deri.org>, public-rif-wg@w3.org
"Gerd Wagner" <wagnerg@tu-cottbus.de> wrote: > > Enrico and Jos, > > yes, the issue of existential information is interesting > (and also in the field of databases there is no consensus > about null values being a good idea or not), but is it > really an urgent issue for RIF? > > Some form of null values (or "blank nodes" or skolem > constants/terms) may be useful, but probably not needed > in phase 1. Do you know of any non-experimental (if not > commercial) rule system that supports existential > information? > > The differences between a constructive LP-style > interpretation of the existential quantifier and > the non-consructive classical logic and DL-style > interpretation seem to be even less relevant for > RIF than the issue itself. > > -Gerd Exactly. From talking to a number of people with real-world RDF experience, I get the impression that b-nodes are used to refer to individuals when it is too inconvenient to give them explicit names. This is just Scolemization. Does anybody have *real-world* RDF experience with cases where truly existential semantics of b-nodes is used? --michael
Received on Thursday, 12 January 2006 16:07:11 UTC