- From: Pat Hayes <phayes@ihmc.us>
- Date: Fri, 14 Dec 2012 23:52:00 -0800
- To: ross.horne@gmail.com
- Cc: Hugh Glaser <hg@ecs.soton.ac.uk>, Lee Feigenbaum <lee@thefigtrees.net>, David Booth <david@dbooth.org>, semantic-web Web <semantic-web@w3.org>
On Dec 14, 2012, at 9:41 AM, Ross Horne wrote: > Thank you for the filtering.. >> On 13 Dec 2012, at 14:41, Lee Feigenbaum <lee@thefigtrees.net> wrote: >> >>> On 12/13/2012 2:00 AM, Pat Hayes wrote: >>>> Another example: a picture of some celebrity standing next to a horse. I have a URI for the celebrity, but I don't have and don't need one for the horse: and if I were to invent one for each horse, then I could no longer query for retrieval of a picture of that person with "a horse", but would have to remember the URi for each of the bloody horses. But nobody gives a damn about the particular horse. >>> >>> Could you explain this more? No, but I could retract it. You are right, the querying works fine with or without the blank node. But the other argument still holds: I don't need, and shouldn't have to invent, a URI for something that does not need to be identified. Particularly if in fact I cannot identify the thing in quesiton. Inventing a URI to "identify" an anonymous horse or an unknown room in a building is simply a mis-use of the very idea of a URI as being a universal identifier. Pat >>> Because I'm picturing just doing: >>> >>> SELECT ?photo { >>> ?photo a :Photograph ; >>> :depicts :ThePerson ; >>> :depicts [ a :Horse ] ; >>> . >>> } >>> >>> ...which works fine whether the horse is represented with a blank node or a URI. >>> >>> Lee > > Yes! That's right. Compelling use cases for blank nodes are covered by > SPARQL. RDF triples *without blank nodes* are adequate and > understandable by everyone. Let SPARQL do the work. > > The List/Collection use case is covered by Turtle where, like in any > other language, lists are primitive e.g. ( uri1 uri2 uri3 ). Let the > primitives be the canonical form and let the bnode encoding be a > historical curiosity. It was a dubious decision to encode lists in the > first place. > > This leads to a half page specification for Well-Behaved RDF with > little or no ambiguity. > > Ross > ------------------------------------------------------------ IHMC (850)434 8903 or (650)494 3973 40 South Alcaniz St. (850)202 4416 office Pensacola (850)202 4440 fax FL 32502 (850)291 0667 mobile phayesAT-SIGNihmc.us http://www.ihmc.us/users/phayes
Received on Saturday, 15 December 2012 07:52:29 UTC