- From: Miles Sabin <miles@mistral.co.uk>
- Date: Thu, 28 Mar 2002 17:32:49 -0000
- To: "'www-tag'" <www-tag@w3.org>
Joshua Allen wrote, > Miles Sabin wrote > > http://www.markbaker.ca/ qua person is Mark Baker > > > > http://www.markbaker.ca/ qua image looks-like > > http://www.joethomas.ca/ qua image > > > > where 'qua P' is a disambiguating operator taking an ambiguous > > URI (which, because ambiguious, doesn't identify any particular > > That seems most appropriate to me, as well -- this is trivial to > represent in triples, and the "qua image" is the part that would > be appropriate to be catalogued in an ontology somewhere. > > And of course, all of this only matters if we are going to let a > URI be overloaded to represent multiple resources, which I am not > so sure is a good idea (what exactly is the benefit of all that > added complexity?) I don't think there's any benefit, per se. It's simply a recognition of the fact that URIs _are_ often ambiguous, and that in at least some cases we need a mechanism for expressing the resolution of that ambiguity. Over the years there've been innumerable wrangles over exactly what unique thing a URI is supposed to refer to, particularly when candidate things aren't electronically retrievable. Dropping the uniqueness assumption looks like it might shift that blockage, * We no longer have to choose which of a set of candidate resources is the "real" resource identified. We just declare the URI ambiguous and leave it at that in the absence of a disambiguator. * We can accommodate non-retrievable resources fairly smoothly. Typically a URI which is declared to refer to a non-retrievable resource (eg. http://www.markbaker.ca referring to Mark Baker) can be used to retrieve an associated resource (ie. the document GET'able at http://www.markbaker.ca). We can declare the URI ambiguous between the two, and note that a GET will implicitly resolve the ambiguity in favour of the document rather than Mark. * We can accomodate multiple levels of abstraction smoothly too. We have a long-standing issue about wether a URI identifies, say, a bunch of bits vs. an instantaneous snapshot of a document vs. an document which changes over time vs. an electronic representation of The Complete Works of Shakespeare vs. The Complete Works of Shakespeare (in the non-instance sense) vs. a web-masters favourite work of literature vs. whatever. We can declare the URI ambiguous between all of these, and allow a disambiguator to take up the slack. If URIs had been used as unambiguous identifers from the outset then none of this would be necessary ... but that's not the way things have worked out. Cheers, Miles
Received on Thursday, 28 March 2002 12:32:51 UTC