- From: Stian Soiland-Reyes <soiland-reyes@cs.manchester.ac.uk>
- Date: Wed, 18 Jan 2012 08:55:16 +0000
- To: Graham Klyne <GK@ninebynine.org>
- Cc: Paolo Missier <Paolo.Missier@ncl.ac.uk>, Luc Moreau <L.Moreau@ecs.soton.ac.uk>, "public-prov-wg@w3.org" <public-prov-wg@w3.org>
On Tue, Jan 17, 2012 at 18:01, Graham Klyne <GK@ninebynine.org> wrote: >> alternateOf(paoloInCafe, customerOnRedChair) >> alternateOf(stianInCafe, customerOnRedChair) > Hmmm... I'm not sure these actually match my intuition about alternateOf; > i.e. that they're both versions of some real-world thing. What real-worlkd > thing would that be? It would be something like the atoms of the living person who sits within the confines of the red chair. Perhaps it is more a case of specialization than alternateOf in this case. (and so a strong case for why specializationOf is not a subproperty of alternateOf) But this thing with the atoms is not true. A customer is not a set of atoms. A cafe *customer* is a concept which depends on the interactions with the cafe. While Paolo was in the cafe, he sat in the red chair and ordered coffee - and so for a period (the full lifetime of paoloInCafe) he also became customerOnRedChair. This would probably be fine then: specializationOf(paoloInCafe, customerOnRedChair) specializationOf(paoloInCafe, paolo) --> alternateOf(paolo, customerOnRedChair) which makes sense - they are both talking about the same thing. but if we also have the equivalent assertions about Stian - but the old characterisation interval of paoloInCafe never overlaps that of stianInCafe - then I feel they should *not* be alternateOf each other, because they did not exist at the same time. So similarly I would not like to conclude alternateOf(Bush, Obama) .. because if we do, then as far as I can tell there is not much value in alternateOf() any more. And that is perhaps my point. We can't have a single hierarchical structure organizing everything that exists (and talk about "the same real world thing"), because we include in "exists" various abstract concepts and simplifications that are not easily mappable to our understanding of the physical world. I am sure we can agree that this email message can be characterised by an entity. However you can't easily map that entity to electrons on the wire or photons coming out of the screen - although we are of course aware that the message would not exists without those. -- Stian Soiland-Reyes, myGrid team School of Computer Science The University of Manchester
Received on Wednesday, 18 January 2012 08:56:07 UTC