- From: Pat Hayes <phayes@ihmc.us>
- Date: Wed, 2 Mar 2011 13:52:54 -0600
- To: Jiří Procházka <ojirio@gmail.com>
- Cc: Reto Bachmann-Gmür <reto.bachmann@trialox.org>, Richard Cyganiak <richard@cyganiak.de>, William Waites <ww@styx.org>, nathan@webr3.org, Ivan Shmakov <oneingray@gmail.com>, semantic-web@w3.org
On Mar 2, 2011, at 1:17 PM, Jiří Procházka wrote: > On 03/02/2011 07:50 PM, Reto Bachmann-Gmür wrote: >> ----- Original message ----- >>> On 03/02/2011 07:21 PM, Pat Hayes wrote: >>>> >>>> On Mar 2, 2011, at 9:54 AM, Richard Cyganiak wrote: >>>> >>>>> On 2 Mar 2011, at 14:18, William Waites wrote: >>>>>> maybe some convention or >>>>>> standard for skolemising blank nodes so they can be >>>>>> referred to might be a good thing? >>>>> >>>>> There is already a convention/standard for skolemising blank nodes: >>>>> just use a URI instead. >>>> >>>> But that subtly changes the RDF, because the URI has global scope. >>> >>> Is there any practical difference between bnodes and normal nodes, >>> except the scope (and necessity) of their name? >> >> Yes, a graph with bnodes can potentially be simplified: the same meaning may be expressed with a more lean graph, i.e. with less nodes and triples. If all your nodes are uris you cannot do simplifications with rdf entaillment. > > So that in fact means that bnodes are considered from a closed world > scenario, where we assume there are no other references to the node > outside of what we know. Um... yes, but please don't use the phrase 'closed world' which means something rather different. Bnodes have local scope, a syntactic issue rather than a semantic one. > On the other hand normal nodes have global > identifier which forces us to consider it from an open world scenario. LIkewise, 'global scope' rather than 'open world', please. Thanks. But yes, what you say is correct. > > To the scoping of the blank nodes: doesn't anyone else think there > should be several types of blank nodes? (example: current graph, current > document, maybe even specific document) We need to get the scope rule(s) clarified, for sure. (More on this topic later.) Maybe we need several kinds of scope, but I hope not. But please lets not code this by having many kinds of node :-(( Pat > > Best, > Jiri > >> Cheers, >> Reto >> >>> >>> Best, >>> Jiri >>> >>>> Pat >>>> >>>>> >>>>> Richard >>>>> >>>>> >>>>>> >>>>>> Cheers, >>>>>> -w >>>>>> -- >>>>>> William Waites <mailto:ww@styx.org> >>>>>> http://river.styx.org/ww/ <sip:ww@styx.org> >>>>>> F4B3 39BF E775 CF42 0BAB 3DF0 BE40 A6DF B06F FD45 >>>>>> >>>>> >>>>> >>>> >>>> ------------------------------------------------------------ >>>> 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 >>>> >>>> >>>> >>>> >>>> >>>> >>> >> >> > ------------------------------------------------------------ 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 Wednesday, 2 March 2011 19:54:00 UTC