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Re: [RSS-DEV] (taxonomy) use and abuse of the URI

From: Seth Russell <seth@robustai.net>
Date: Sat, 14 Oct 2000 10:55:38 -0700
Message-ID: <39E89E1A.1EAC299A@robustai.net>
To: rss-dev@egroups.com
CC: rdf <www-rdf-interest@w3.org>
Aaron, I think both you and Eric missed my point.  We want the uri to be unique
_AND_ we want to allow variations.  We want it to unique so that RDF statements
talking about  the same thing will end up sorting together as the same subject (see
demonstration below).  Outside of its use as a locator, that is (imho) the only
purpose of the URI.    At the same time we want to grant people the right to
designate different URI to express their different points of view.  For the Semantic
Web community to meet both of these (contradictory) goals, we need to walk a very
narrow tight rope.  I think what we want to say to the RDF writers is:  try to find
a URI for your subject that is already in use;  but if none references exactly what
you want to designate, then make one up only if you are prepared to defend it;  and
in any case be consistent - otherwise make the subject anonymous.  To RDF readers
reading feeds from multiple authors, I think we need to say:  maintain your own
internal identity system and be aware that  you will need to be doing some fuzzy
matching to get foreign RDF to sort into it coherently.

What we definitely do not want to do is to make up a URI on somebody else's
namespace.  This breaks TBL's axiom 2b: identity: " the significance of identity for
a given URI is determined by the person who owns the URI, who first determined what
it points to." [3]

Demonstration: Switch between these tow slides by TBL and think of the different
colors as coming from different RDF sources:
[1] http://www.w3.org/2000/Talks/0906-xmlweb-tbl/slide6-0.html
[2] http://www.w3.org/2000/Talks/0906-xmlweb-tbl/slide7-0.html

[3] http://www.w3.org/DesignIssues/Axioms.html#same

cc: www-rdf-interest@w3.org
Seth

---- a little history ----
Aaron Swartz wrote:

> Seth Russell <seth@robustai.net> wrote:
>
> > When language works, it works because each of us uses the same word for the
> > same thing.   So the semantic web is trying to make its language work by using
> > the same URI for the same thing.
> >
> > *** But if we use different URIs for the same thing, it doesn't work! ***
>
> Hmm, let's try replacing URI with word, as you've implied above:
>
> *** But if we use different words for the same thing, it doesn't work! ***
>
> Have you looked at a thesaurus recently? ;-)
>
> Anyway, the point is, that it's perfectly OK to have multiple words (or
> URIs, as the case may be) that represent a subject. They all have slightly
> different meanings, but one can say (or make an RDF assertion) that they're
> all similar, or represent the same thing.
>
> Now for a specific example:
>
> > But if everybody makes up their own URI for WAP it will be just wasted energy.
> > I will just end up with a <rdf:Bag> of different URIs; and when MyMemory
> > writes RDF to others about WAP it will not know which one to output.
>
> The easiest solution would be for it to output it's own:
>
> http://RobustAi.net/MyKB/seth@robustai.net/topics/WAP/
>
> However, you do have a valid point, one which I've recently made at the
> W3C's URI list:
>
> "With the increasing popularity of URIs, especially with their increased
> importance in RDF, it becomes more important than ever to have URIs for all
> sorts of items. Already, protocols like isbn: allow the use of some types of
> physical items, but this still leaves quite a lot left."
>
> http://lists.w3.org/Archives/Public/uri/2000Oct/0006.html
>
> It would be nice to have official URIs for these things.
>
> --
>         Aaron Swartz         |"This information is top security.
> <http://swartzfam.com/aaron/>|     When you have read it, destroy yourself."
>   <http://www.theinfo.org/>  |             - Marshall McLuhan
>
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Received on Saturday, 14 October 2000 13:46:28 GMT

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