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RE: Madonna

From: Spork, Murray <murray.spork@sap.com>
Date: Wed, 9 Feb 2005 19:00:16 +0800
Message-ID: <427A3C83BA264C49A6E9C14BF514B7475F269C@sgsine10.sin.sap.corp>
To: "Henry Story" <henry.story@bblfish.net>, <semantic-web@w3.org>

[Cc's trimmed]

Hi Henry,

I was going to point you towards a keynote speech at Extreme Markup
Languages 2003 by Bill Kent on the "Unsolvable Identity Problem" but
can't find it anywhere - the best I can find is [1].

Doesn anyone know if it's available online? I'm sure it used to be.

Kent's book "Data and Reality" [2] is essential reading (and a little
depressing for all of us interested in the "semantics" of data) - just
as relevant now as it was in the 70s when written.

[1] http://www.extrememarkup.com/extreme/2003/keynotes.asp

>-----Original Message-----
>From: semantic-web-request@w3.org 
>[mailto:semantic-web-request@w3.org] On Behalf Of Henry Story
>Sent: Wednesday,9 February 2005 7:42 PM
>To: semantic-web@w3.org
>Cc: Roy T. Fielding; Atom Syntax; bloged
>Subject: Madonna
>Just a point of clarification about identity. (I thought the example
>is fun enough that it may be of interest)
>As we all know Madonna is a material girl, and she lives in a material
>world [1].
>Madonna is a US citizen also. Let us imagine the day she received her
>social security card through the post. That day Madonna, the material
>girl, had a very specific material constitution. Let us call the set
>of cells, organic and inorganic material that composed Madonna that
>moment M1.
>Now let us stipulate that two material things are equal if they are
>made of exactly the same matter.
>That afternoon Madonna goes to the beauty salon where she gets her hair
>cut and fingernails and toe nails clipped. The resulting material girl
>call her M2 is no longer the same as M1, as M2 is M1 less some hair
>and nail material. M2 may also contain a little more water (she was
>drinking some beauty drink during the process). So M1 is not the same
>material thing as M2.
>Both M1 and M2 are also girls, and have a functional relation to a
>social security number. Ie M1 and M2 each only have 1 social security
>number. There are in fact a very large number of such material Madonnas
>Mx that have a functional relation to that same social security number.
>So clearly the inverse relation (from social security to temporal 
>Material Madonnas) is not functional.
>Now let us think of the mereological fusion [2] of all of these
>Material Madonnas, and let us call that MM. MM also has a functional
>relation to the social security number. But it is also clear that
>there is an inverse functional relation from social security number
>to MM.
>So the social security number identifies madonna in two ways.
>1. via a functional relation
>     temporalId:  temporal material madonnas --> social security number
>2. via an inverse functional relation
>     fusionId: MM --> social security number
>Given a social security number we can via the fusionId relation
>get a hold of the mereological fusion of that person, and from
>the mereological fusion we can find the individual temporal parts,
>each of which of course have a temporalId relation to the same social
>security number.
>The above can probably be also put in terms of set theory, and
>so in terms of rdf graphs. In which case it clearly shows how
>rdf can speak about temporal and non temporal identity.
>Henry Story
>[1] http://www.lyricsfreak.com/m/madonna/86925.html
>     audio clip: http://tinyurl.com/5k9et
>[2] http://plato.stanford.edu/entries/mereology/
Received on Wednesday, 9 February 2005 11:01:28 UTC

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