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Re: URI lifecycle (Was: Owning URIs)

From: David Booth <david@dbooth.org>
Date: Mon, 25 May 2009 11:45:41 -0400
To: Dan Brickley <danbri@danbri.org>
Cc: Pat Hayes <phayes@ihmc.us>, Hugh Glaser <hg@ecs.soton.ac.uk>, semantic-web <semantic-web@w3.org>, Linked Data community <public-lod@w3.org>
Message-Id: <1243266342.17404.354.camel@dbooth-laptop>
On Fri, 2009-05-22 at 20:49 +0200, Dan Brickley wrote:
> On 22/5/09 19:47, Pat Hayes wrote:
> >> David Booth wrote:
> >> Yes, that's a great topic for discussion. It is clear that semantic
> >> drift is a natural part of natural language: a word that meant one thing
> >> years ago may mean something quite different now.
> >
> > And the same is happening with URIs. 
[ . . . ]
> foaf:schoolHomepage. This is a property originally created by brits for 
> whom School is where you go until you're at most 18. After which it's 
> off to University, College, Tescos, or whatever YTS schemes are called 
> these days. *However* ... shortly after deploying foaf:schoolHomepage, 
> it became clear that it meant something quite different to USAmericans 
> and presumably others. We started seeing instance data where people were 
> asserting foaf:schoolHomepage between themselves and the homepage of 
> their University. This was unexpected, but not really suprising.
> Being a pragmatist, I updated 
> http://xmlns.com/foaf/spec/#term_schoolHomepage  ...
> It now mentions this drift explicitly: "The original application area 
> for foaf:schoolHomepage was for 'schools' in the British-English sense; 
> however American-English usage has dominated, and it is now perfectly 
> reasonable to describe Universities, Colleges and post-graduate study 
> using foaf:schoolHomepage."

That's an interesting example.  As described, it sounds like the
American interpretation was actually *consistent* with the original
definition, but the original definition meant different things to
different readers, and the original authors had not anticipated this.

That example does not sound at all like an argument against semantic
anchoring.  Rather, it sounds like an example in which a URI declaration
turned out to be less constraining than originally thought.  The point
of a URI declaration is not to forbid semantic variability, it is to
permit the bounds of that variability to be easily prescribed and

[ . . . ]
> >> In short, although semantic web architecture could be designed to permit
> >> unrestricted semantic drift, I think it is a better design -- better
> >> serving the semantic web community as a whole -- to adopt an
> >> architecture that permits the semantics of each URI to be anchored, by
> >> use of a URI declaration.
> >
> > And I disagree.
> Seconded. But perhaps for different reasons. We need to leave some 
> flexibility in the system so that the most useful uses of classes and 
> properties can emerge from experimentation and deployment.

Again, the point is not to *forbid* semantic flexibility, but to permit
that semantic flexibility to be clearly constrained.  There *are*
important use cases in which it is advantageous to evolve a URI
declaration over time, or to have an intentionally broad URI
declaration.  But use cases where the semantics of a URI are anchored
are also important, and should not be prevented just because other use
cases need more variability.

David Booth, Ph.D.
Cleveland Clinic (contractor)

Opinions expressed herein are those of the author and do not necessarily
reflect those of Cleveland Clinic.
Received on Monday, 25 May 2009 15:46:21 UTC

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