- From: Pat Hayes <phayes@ihmc.us>
- Date: 2012年11月14日 09:40:25 -0800
- To: Cory Casanave <cory-c@modeldriven.com>
- Cc: "nathan@webr3.org" <nathan@webr3.org>, Sergey Larionov <s.larionov@rks.karelia.ru>, Semantic Web <semantic-web@w3.org>
- Message-Id: <12666691-5ABB-4D00-AAD7-D708DFE6BACE@ihmc.us>
On Nov 14, 2012, at 8:36 AM, Cory Casanave wrote: > Re: It assumes, implicitly, that URI references have the same meaning whenever they occur." > > That assumption seems to have been overtaken by events, technologies and usage over time. Over time, hah. Possibly, although I know that many users of RDF do in fact use it "properly" in this regard. For sure, there seems to be a conceptual gap between users who think of RDF as timeless and those who see it as a vehicle for time-sensitive information. And as long as this gap exists, mutual incomprehension will occur. I am not sure what we can do about this situation, unfortunately. Pat > >> -----Original Message----- >> From: Pat Hayes [mailto:phayes@ihmc.us] >> Sent: Wednesday, November 14, 2012 11:27 AM >> To: nathan@webr3.org >> Cc: Sergey Larionov; Semantic Web >> Subject: Re: rdf semantics and timelessly true >> >> >> On Nov 14, 2012, at 8:03 AM, Nathan wrote: >> >>> Hi Pat, >>> >>> Pat Hayes wrote: >>>> Its not impossible, and in a strong sense this is required by the current RDF >> semantics, which treats all RDF assertions as timelessly true. >>> >>> Can you refine / expand on this please? I'd presumed RDF to have no >> consideration of time - e.g time-less; as opposed to being true for all time >> (timeless). >>> >>> TIA, >>> >>> Nathan >> >> Yes, time-less is a better way to put it. But it is so because URIreferences are >> assumed (and I know this is an idealization, but...) to be timeless in how they >> refer. Section 1.2 says: "... the semantics simply assumes that ... a single URI >> reference can be taken to have the same meaning wherever it occurs. Similarly, >> the semantics has no special provision for tracking temporal changes. It >> assumes, implicitly, that URI references have the same meaning whenever they >> occur." >> >> In other words, no counters allowed. >> >> Pat >> >> >>> >>> >> >> ------------------------------------------------------------ >> 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, 14 November 2012 17:40:59 UTC