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Re: Mistaken identity?

From: Mark Baker <distobj@acm.org>
Date: Tue, 22 Jun 2004 09:23:20 -0400
To: Danny Ayers <danny666@virgilio.it>
Cc: www-rdf-interest@w3.org, ken@bitsko.slc.ut.us, Norman.Walsh@Sun.COM
Message-ID: <20040622132320.GB16599@markbaker.ca>

On Tue, Jun 22, 2004 at 01:20:49PM +0200, Danny Ayers wrote:
> I'm seeking a little clarification of the nature of identity on the web, 
> several related issues involved. In short, here are three little puzzles:
> 
> 1. Can a resource have multiple different representations of the same type?

Sure.  See Dan's example.  In addition to language variability, there's
an infinite number of other factors that a representation of the same
type (presumably you mean Internet media type) may vary over.

> 2. If two resources have different sets of representations, can they 
> ever be considered the same?

Sure.  Somebody observing a clock every hour on the hour will receive
different representations than somebody else observing a clock every
hour on the half hour, yet it's the same clock reporting the current
time.

Perceived identity is a function of the *observed* representations.

> 3. How can I ever assert:
> 
> <http://mydomain.org/a> owl:sameAs <http://yourdomain.org/a> .
> 
> when I can't ever be sure that you aren't going to change 
> http://yourdomain.org/a ?

I can see two cases when you'd assert that.  One would be when I've
agreed not to change it, and the other would be when you've committed
to making that statement true, by returning representations consistent
with it being true.

Mark.
-- 
Mark Baker.   Ottawa, Ontario, CANADA.        http://www.markbaker.ca

  Seeking work on large scale application/data integration projects
  and/or the enabling infrastructure for same.
Received on Tuesday, 22 June 2004 09:23:17 GMT

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