- From: Paul Prescod <paul@prescod.net>
- Date: Sun, 24 Nov 2002 16:43:04 -0800
- To: Alexander Jerusalem <ajeru@vknn.org>, www-rdf-interest@w3.org
Alexander Jerusalem wrote: > I'm not sure if the following is of any relevance for this thread but > your discussion reminds me of a question I have always had regarding RDF: > > URIs, it seems to me, are used in two completely different ways: On > the one hand they are just unique names for something. On the other > hand they are used to point to something and provide a kind of > processing instruction that allows us to physically retrieve the > thing it points to. Yes, they are identifiers and locators. Identifiers first, locators second. > Now when we talk about someone's homepage for example, I don't think > it is appropriate to use the URL that allows us to physically retrieve > the homepage as the unique name of the homepage. The two roles should > be strictly separated. The reason is that I could have made a lot of > statements about the homepage that use this URI as a unique name, that > is as their subject. The physical address, however, can change. If the address of the thing changes, then according to web infrastructure, it is basically a new thing that happens to have the same content as the old thing. * http://www.w3.org/Provider/Style/URI.html The word "physical" is used in a funny way in computer science discussions. There is no such thing as a physical URI. They are all interpreted by server software so that there is no reason in principle to _ever_ change a URI except for limitations of implementation technology or effort. Anyhow, why not use RDF to make the assertion that the new page is daml:equivalentTo the old one (or be more precise and say something like the new URI supercedes the old one). > So even for internet resources, I think we should have one URI to name > it and another one to point at it, even if the two happen to have the > same sequence of characters at any one point in time. Discussed here: http://www.w3.org/DesignIssues/Axioms.html#Properties Paul Prescod
Received on Sunday, 24 November 2002 19:43:37 UTC