- From: Bijan Parsia <bparsia@cs.man.ac.uk>
- Date: Thu, 17 Jan 2008 14:43:47 +0000
- To: Jeremy Carroll <jjc@hpl.hp.com>
- Cc: "Web Ontology Language ((OWL)) Working Group WG" <public-owl-wg@w3.org>
On 17 Jan 2008, at 14:22, Jeremy Carroll wrote: > Bijan Parsia wrote: >> Furthermore such variables have far reaching consquences both >> formally (e.g., on the data complexity of RDFS; undecidability of >> OWL DL+ cyclic bnode patterns; what sorts of entailments occur) > > Remind me about the "undecidability of OWL DL+ cyclic bnode > patterns" - I seem to vaguely remember briefly getting my head > round it once, but it's gone. See Boris' explanation: http://www.w3.org/mid/000701c82200$d343cf00$2711a8c0@wolf > Is the statement that say using the existential semantics with > bnodes for individuals in OWL DL takes us into undecidability? IIRC, you need inequality as well, but yes. Ah yes, see his even earlier explanation: http://www.w3.org/mid/000601c82176$e8a3b700$2711a8c0@wolf It contains the reference. Cheers, Bijan.
Received on Thursday, 17 January 2008 14:42:00 UTC