- From: Patrick Stickler <patrick.stickler@nokia.com>
- Date: Thu, 27 Jun 2002 15:44:54 +0300
- To: ext Jonathan Borden <jonathan@openhealth.org>, Danny Ayers <danny666@virgilio.it>, RDF Logic <www-rdf-logic@w3.org>
On 2002-06-27 14:39, "ext Jonathan Borden" <jonathan@openhealth.org> wrote: > > Danny Ayers wrote: >> >> So essentially I'm suggesting two aspects to the context/grouping issue, >> firstly that in the wild (on the web or otherwise available through public >> interfaces) the triples exist implicitly as quads, i.e. >> >> [email:765] [urn:Sassi] [a:hasSpecies] [a:cat] >> >> and that whether or not triples get asserted remains entirely a local > issue, >> decided by the implementation. >> >> Putting this more strongly, we only really have two contexts - 'in the > wild' >> and 'in application X'. >> > > Whether triples get asserted is not entirely a local issue, nor should it > be. > > Consider above, that your triples are "colored" by the base URI of their > containing document, in this case your e-mail. Now consider a "current > document" which is identified (as always) by a URI. > > In base RDF, a triple is _asserted_ when its color (i.e. base URI) is equal > to the "current document" URI. Now how one determines the "current document" > is outside the scope of RDF, and needs to be more formally addressed for a > semantic web to get working. This is similar to how I have been thinking about statement qualification. Rather than quads, simply have qualified reified statements (statings) with arbitrary properties: source, scope, authority, layer (e.g. OWL) etc. and the 'live' knowledge base then simply becomes a dynamic view into the sandbox by defining selection criteria for reified statements based on any number of qualifications. Thus, one can "virtually assert" statements from multiple sources, authorities, scopes, etc in any combination. And inferred statements could be expressed as reified statements with a session specific scope qualification, which treats them as asserted for that session and also allows those statements to be conveniently purged later when no longer needed. This is useful e.g. in a mobile context where clients may enter a context, make queries and requests from local servers which require inference, and then leave that context and thus the knowledge about the client and the clients inquiries are transient and should not be saved persistently. Cheers, Patrick -- Patrick Stickler Phone: +358 50 483 9453 Senior Research Scientist Fax: +358 7180 35409 Nokia Research Center Email: patrick.stickler@nokia.com
Received on Thursday, 27 June 2002 08:40:22 UTC