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Re: additional issue-57 use case: polysemy

From: Henry S. Thompson <ht@inf.ed.ac.uk>
Date: Tue, 05 Jun 2012 18:20:48 +0100
To: Jonathan A Rees <rees@mumble.net>
Cc: www-tag@w3.org
Message-ID: <f5blik11xqn.fsf@calexico.inf.ed.ac.uk>
Jonathan A Rees writes:

> I added a new use case
>  http://www.w3.org/wiki/HTTPURIUseCases#N.29_Reconciling_incompatible_uses_.28polysemy.29
> to the use case list and to the matrix
>  http://www.w3.org/wiki/HTTPURIUseCaseMatrix

I find this too brief to be illuminating.  In particular, although I
understand how "the messages being composed at different times" could
lead to the _messages_ having different _truth values_, I don't
understand how it could lead to the URI U having different meanings.

Consider the cast of U = "http://www.w3.org/TR/xml/".  In a message
sent today a triple such as

 <http://www.w3.org/TR/xml> dc:title
     "Extensible Markup Language (XML) 1.0 (Fourth Edition)" .

is false, but if sent in 2007 it would be true.  But I don't
understand the reason this is the case to be because the meaning of U
has changed -- it hasn't, it is now what it was in 2007, namely what
it's promised to be by the W3C publication policy, approximately "The
most recent available edition of the specification with U as its
shortname" in general, or, "The most recent available edition of the
XML specification" in particular.

[Note this is _not_ a comment about the document/resource distinction,
as I take it the title of _both_ is the same in this case. . .]

Could you elaborate a bit with an example where the meaning of U is
clearly what changes?  My efforts to imagine one have gotten tangled
up in the alleged/assumed monotonicity of RDF . . .

ht
-- 
       Henry S. Thompson, School of Informatics, University of Edinburgh
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Received on Tuesday, 5 June 2012 17:23:43 UTC

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