- From: Deborah McGuinness <dlm@KSL.Stanford.EDU>
- Date: Mon, 25 Feb 2002 19:29:39 -0800
- To: Frank van Harmelen <Frank.van.Harmelen@cs.vu.nl>
- CC: WebOnt <www-webont-wg@w3.org>
one minor suggestion follows. this is motivated by my experiences in configuration where it was important to be able to make closed world statements. frank suggested: Therefore, the language must be able to state that a given ontolog can be regarded as complete. This would then sanction additional inferences to be drawn from that ontology. The precise semantics of such a statement (and the corresponding set of inferences) remains to be defined, but examples might include assuming completeness of class-membership and assuming exhaustiveness of subclasses. i suggest the minor modification: Therefore, the language must be able to state that a given ontolog can be regarded as complete. This would then sanction additional inferences to be drawn from that ontology. The precise semantics of such a statement (and the corresponding set of inferences) remains to be defined, but examples might include assuming complete property information about individuals, assuming completeness of class-membership, and assuming exhaustiveness of subclasses. Frank van Harmelen wrote: > Current wording: > > Due to the size and rate of change on the Web, the closed-world assumption > (which states that anything that cannot not be inferred is assumed to be > false) is inappropriate. However, there are many situations where closed-world > information would be useful. Therefore, the language must be able to specify > when certain documents have complete information on certain topics. Examples > might include the complete set of instances of a class or the complete set of > members in a list. > > Proposed Wording: > > ... two sentenced remain unchanged ... > Therefore, the language must be able to state that a given ontolog can be > regarded as complete. This would then sanction additional inferences to be > drawn from that ontology. The precise semantics of such a statement (and the > corresponding set of inferences) remains to be defined, but examples might > include assuming completeness of class-membership and assuming exhaustiveness > of subclasses. > > Comments: > 1. I refer to Pat's email [1] for keeping this on board > 2. I tried to make the issue clear while keeping the details open as much as > possible (there is clearly work to be done here). > > Frank. > ---- > > [1] http://lists.w3.org/Archives/Public/www-webont-wg/2002Feb/0098.html -- Deborah L. McGuinness Knowledge Systems Laboratory Gates Computer Science Building, 2A Room 241 Stanford University, Stanford, CA 94305-9020 email: dlm@ksl.stanford.edu URL: http://ksl.stanford.edu/people/dlm/index.html (voice) 650 723 9770 (stanford fax) 650 725 5850 (computer fax) 801 705 0941
Received on Monday, 25 February 2002 22:34:17 UTC