- From: David Booth <david@dbooth.org>
- Date: Thu, 30 Jun 2011 12:01:44 -0400
- To: Jonathan Rees <jar@creativecommons.org>
- Cc: www-tag@w3.org
On Thu, 2011-06-30 at 10:32 -0400, Jonathan Rees wrote: > I had a thought about the TAG definition discovery and metadata > architecture issues that might be helpful. Probably this is obvious, but > it wasn't to me so I thought it was worth writing down. This relates > to the fact that whenever the httpRange-14 thing comes up in the TAG > we are confused about what issue to put it under. I was inspired to > think this over by F2F remarks of Larry's about the magnitude of > the problem. > > There are two distinct application-level communication needs: > > 1. web metadata - when I express information about a document > (image, etc.) how do I say (especially in RDF) that what I am > talking about is content that's accessed via a particular URI, as > opposed to other content > > 2. definition discovery - given a vocabulary term (URI), > how is definition-like information for it discovered > (Definitions are not, in general, metadata.) > > Described in this way, the needs seem unrelated. The first falls > under our ISSUE-63 (metadata architecture), the second under ISSUE-57 > (definition discovery). The first need spawned the Resource > Description Framework and the httpRange-14 2xx rule, while the second > spawned linked data, RDF-style fragment ids, and GET+303. > > The connection between them is that the same notation and protocol, > namely what I've been calling dereferencable absolute URIs, has been > advanced as a solution to both problems. The competition creates a > struggle. Think of these URIs as a limited natural resource over > which many factions are contending. Just as a piece of real estate > cannot be used for a wetlands and a high-rise at the same time, one of > these URIs can't simultaneously get its meaning according to two rules > that give different answers most of the time. > > So the competition over "linguistic real estate" itself begets a third > problem: > > 3. to what referential use are dereferenceable absolute URIs best > put? > > One might then give up and say interoperability is not a good goal, > one might try to carve up or overload the linguistic space, one might > try to "win", one might say it's an inadequate solution for one or the > other problem, or that it's hopeless, and so on - all the arguments > we've heard over and over again. > > It's not enough to solve the three problems separately. There is > no divide-and-conquer. That is what makes it so annoying: everything > interacts. Interesting observation. However, it seems to me that although #2 clearly involves using the URI referentially, #1 does not *require* using the URI referentially. For example, instead of using http://example/bar referentially by writing something like: :fred p1:authored <http://example/bar> . to indicate that :fred authored the content accessed from http://example/bar , one could just as well express this using a different property like: :fred p2:authored "http://example/bar" . in which the URI is used as a literal. This seems like another way the conflict could be avoided. -- David Booth, Ph.D. http://dbooth.org/ Opinions expressed herein are those of the author and do not necessarily reflect those of his employer.
Received on Thursday, 30 June 2011 16:02:07 UTC