- From: Bijan Parsia <bparsia@cs.man.ac.uk>
- Date: Thu, 16 Aug 2007 20:39:39 +0100
- To: "Swanson, Tim" <tim.swanson@semanticarts.com>
- Cc: "Matt Williams" <matthew.williams@cancer.org.uk>, "Owl Dev" <public-owl-dev@w3.org>
On Aug 16, 2007, at 8:28 PM, Swanson, Tim wrote: > Bijan, > > Thanks again. I think you're right, the misunderstanding goes back to > talking at cross-purposes. I have just one more question. > >>> (Admittedly, this is not the same thing as "directly" checking for >> the >>> negative entailment, since it relies on the user's understanding of >>> OWL >>> semantics to make the jump from membership in the above class to the >>> negative entailment.) >> >> It's not a negative entailment (which for me means a *failure* to >> entail) but an entailment of a negation, but yes. For Matt's purpose >> this might be fine. OWL 1.1 statement entailment shall be added to >> Pellet in due course (esp to support SPARQL). One could, of course, >> write such a wrapper. >> > > "negative entailment" = "failure to entail" (i.e. still unknown in the > open world) More typically known as "non-entailment" (e.g., non-subsumption as well). I've never specifically heard "negative entailment" before, so I see I read it as a variant of "non-entailment". > "entailment of a negation" = "entailing that something is > untrue" (i.e. > known to be false) Well, the *negation* is true (entailed), but of course the negated sentence is false. > Is this the accepted language? (If so, I need to re-write some of our > in-house documents to comply with it.) I feel that the above is standard. Cheers, Bijan.
Received on Thursday, 16 August 2007 19:39:51 UTC