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Re: context (comments on http://www.w3.org/TR/2002/WD-rdf-schema-20021112/)

From: pat hayes <phayes@ai.uwf.edu>
Date: Tue, 3 Dec 2002 14:39:01 -0600
Message-Id: <p05111b1aba12c2b5f307@[10.0.100.247]>
To: "Richard H. McCullough" <rhm@cdepot.net>
Cc: "Brian McBride" <bwm@hplb.hpl.hp.com>, <www-rdf-comments@w3.org>
>Just two quick comments on context -- stimulated by your previous 
>comments on context.
>
>1. Context is always important. 

I might take that comment seriously if I knew what it meant.

>Here's a trivial example.
>         Dick McCullough is married.
>In the context of December 2002, this statement is false. 
>In the context of any time between June 1960 and September 1996, it's true.

No. It was true AT one time but not AT another; or, it was true OF 
one time but not OF another; or, it is incompletely specified as 
stated and hence neither true not false, but rather something like a 
predicate which applies to temporally located entities.

>
>Here's another example.
>         Names denote things in the universe, and sets of triples 
>denote truth-values.
>which is true in the context of your document 
><http://www.w3.org/TR/2002/WD-rdf-mt-20021112/>http://www.w3.org/TR/2002/WD-rdf-mt-20021112/
>but is false in the context of my document 
><http://rhm.cdepot.net/doc/KEtutorial.txt>http://rhm.cdepot.net/doc/KEtutorial.txt.

Documents are not contexts in your first sense, and truth is not 
defined with respect to documents in any case.

>
>2. Knowledge is advanced by integrating facts into a wider context. 
>For example, in physics,
>         force = mass x acceleration
>is a principle which integrates observed facts from many different 
>contexts into a single context. 

Nonsense. Cite me any physics textbook which refers to such a notion 
of 'context'.

>By expanding that context to include variable mass and acceleration, 
>we get a broader principle
>         force = rate of change of momentum

Your message illustrates the central problem with the word 'context': 
it means everything, and so it means nothing. You use it above in 
three distinct senses which have got nothing whatever to do with one 
another, and it has been used to mean anything from a single token of 
a phrase in a particular utterance to an entire culture or human 
epoch. I have been to maybe six or seven workshops, colloquia, etc., 
on the topic of 'context' and I don't think I have yet heard two 
people agree on a definition of the word. On one memorable occasion I 
listened to talks every hour for 3 working days, and kept careful 
records, and NONE of them agreed with ANY of the others.  My own 
considered opinion is that 'context' is a kind of dustbin category, 
used by people to refer to that part of the problem of specifying 
meaning they don't yet understand properly.

If you can come up with something like a definition of what you mean, 
I would be interested in discussing how to formalize it. Your first 
sense, which has to do with temporal distinctions, has already been 
thoroughly analyzed and formally specified.

Pat

>============
>Dick McCullough
><http://rhm.cdepot.net/>knowledge := man do identify od existent done
>knowledge haspart proposition list


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Received on Tuesday, 3 December 2002 15:38:45 GMT

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