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Re: What if two resources are the same subject?

From: Charles McCathieNevile <charles@w3.org>
Date: Tue, 13 Apr 2004 14:17:07 -0400 (EDT)
To: Jon Hanna <jon@hackcraft.net>
Cc: "www-rdf-interest@w3.org" <www-rdf-interest@w3.org>
Message-ID: <Pine.LNX.4.55.0404131406370.28932@homer.w3.org>

my 2 cents worth

This gets to the Best Practices discussions about whether it is better to
re-use something that exists, or invent something for yourself... As far as I
can tell there isn't a universal answer since you need to consider the
details each time, but in general it seems more helpful to re-use something.
The downside of this will be that over time those things will come to have
slightly less precise meanings, as people misinterpret in subtle ways what
was meant (again, "Ireland" is a good example).

In the long run we can describe different actual uses of "Ireland" (or
whatever) with newly minted identifiers that will clarify which
interpretation we were after. Which will work for a while... This isn't a
limitation of technology, but one of the way that large groups of people
interact. I suspect that as long as things work more or less peopel will keep
using something familiar, and eventually some new terms will take over.

In natural language, the term obligated is starting to take over from what I
mean when I say obliged - this is a slow process, and language, while not
mathematically precise, seems to work tolerably well for most communication
needs - at least when compared to alternative systems - in part because it
does have some ability to change with usage.

On Tue, 13 Apr 2004, Jon Hanna wrote:

>Quoting Jan Algermissen <jalgermissen@topicmapping.com>:
>> From a Semantic Web-user's perspective: How do I find out statements about
>> Canada?
>> How do I know which URL to use or supposed I know both, can I use any of them
>> or do I have to submit my 'questions' once for every URL?
>
>You can use either. If your tools know that
><http://www.some.org/countries/canada> <owl:sameIndividualAs>
><http://another.org/public/countries/Canada> . Then they can do the necessary
>leg work for you.

If they don't know that, then you need to submit your questions again using
each of the identifiers - which is what motivates things like OWL in the
first place :-)

>Of course sometimes there can be subtle differences (e.g. "Ireland" the island
>vs. "Ireland" the country) and sometimes those differences can be contentious
>(e.g. Ireland again).

>You do need to "know" that they two URIs identify the same resource. Sometimes
>this will be published somewhere (ideally either or both URIs when dereferenced
>would reveal this fact). It might not be that easy to determine though, it
>might even be secret (Superman owl:sameIndividualAs Clark Kent, but he doesn't
>want anyone to know :)

(there are two kinds of people in the world - those who think a binary
distinction is useful or interesting, and those who realise that it is a
totally arbitrary and highly context dependent statement whose value rarely
justifies the effort of writing it down :-)
Received on Tuesday, 13 April 2004 14:17:09 GMT

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