- From: Dan Brickley <danbri@danbri.org>
- Date: Thu, 14 Jun 2007 12:17:20 +0100
- To: Bernard Vatant <bernard.vatant@mondeca.com>
- CC: semantic-web@w3.org
Bernard Vatant wrote: > > Just to hit this owl:sameAs (ab)use nail a bit more. > > Although I agree with Pat below (see my previous message) suppose I (or > Richard) disagree(s) and want(s) to stick to the assertion > http://dbpedia.org/resource/Berlin owl:sameAs > http://sws.geonames.org/2950159/ > > Does that mean that what I get from the two resources should be not only > consistent RDF descriptions, but *identical descriptions* ? I guess so. > It's clear that it's not the current case. The point is, according to the owl:sameAs claim, there aren't two resources, just one. One thing - with (at least two names (URIs). Asking an information system (such as the Web itself, or a library catalogue) about this thing could reasonably elicit different answers, depending on which name is used. That doesn't mean there are two things. Similarly, in the real world, different people and info systems known different things about me; they may even consider me to have different names/URIs. But there's only one me. And so, anything true of me, is true of me. Some things might be true of one of my *names* (eg. that it is mentioned in a particular database). So yup, owl:sameAs is a pretty strong claim. Anything true of the one should be true of the other; because there is just the one.(*) Whether an HTTP GET that returns a 200 should always return the same thing, ... is an interesting question. It's certainly (if we believe the HTTP responses, and we believe the owl:sameAs claim) supposed to be considered an interaction with the same thing. But plenty of URIs return different or random or context-specific responses. http://spypixel.com/2006/spanglish/futurebot.cgi names the self-same resource as http://spypixel.com/2006/spanglish/futurebot.cgi (not becaues of owl:sameAs, but because it is the same URI :) ... yet two GETs typically get different HTTP answers. Dan (*) tiptoing past philosophers of language here
Received on Thursday, 14 June 2007 11:17:36 UTC