- From: Vaughan Pratt <pratt@cs.stanford.edu>
- Date: Wed, 07 Mar 2007 12:28:12 -0800
- CC: semantic-web@w3.org, public-owl-dev@w3.org
Bijan Parsia wrote: > Well, disjointness is *weaker* than full negation. For example, in OWL, > A disjointWith B is just syntactic sugar for A subclassof complementOf(B). Are there technical (e.g. computational complexity) benefits to this definition over the more usual (and more constructive) definition in terms of emptiness of intersectionOf(A,B)? This is a non-issue as long as the semantics of set operations remains Boolean, where the two definitions are trivially equivalent. However it may be useful sometimes to use less than the full gamut of Boolean operations, and it would be nice if constructive concepts like disjointness didn't then disappear merely because they'd been defined using nonconstructive concepts like complementOf. (Sorry if I seem to be nagging about trivialities.) Vaughan Pratt
Received on Wednesday, 7 March 2007 20:28:34 UTC