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the 4 colour theorem, and an alternative to the current list of guidelines.

From: Jonathan Chetwynd <j.chetwynd@btinternet.com>
Date: Mon, 20 Aug 2001 07:21:11 +0100
Message-ID: <003f01c12940$4e94b9a0$0f8c7bd5@btopenworld.com>
To: <w3c-wai-gl@w3.org>
perhaps, this would serve as a good analogy to explain the variety of
simplicity, and help explain why we need an alternative to the current

we have:

a name:
the 4 colour theorem

a title:
Every planar map is four colorable

a brief description:
Is it possible to colour any map, so that no borders share the same colour,
using only 4 colours?
or similar

an illustration:

a game:

a new simpler proof:

a reference to a currently accepted proof:
K. Appel and W. Haken, Every planar map is four colorable. Part I.
Discharging, Illinois J. Math. 21 (1977), 429-490.

a description of the problem with this proof:
"(it) is extraordinarily complicated and tedious, and as far as we know, no
one has verified it in its entirety." see a new simpler proof.

a test?
well if there was one.....

It is unlikely that accessibility will be solved in the near future.
The proof of the 4 colour theorem is generally accepted to be understood by
very few, this may help those having problems relating to issues relating to

We need to understand that users have different preferred learning methods,
and those reading the guidelines are presumably seeking to learn.
Not everyone prefers lists, some (like me) prefer to steal code snippets
from working examples, others like complete working modules like .class,
yet others like wizards, some prefer a workbook which takes one thru each
term with tests of partial learning, many enjoy playing a game with levels,
plenty learn from good audio-visual materials some of which offer
interactive tests. The list is endless, and I strongly recommend offering an
alternative to the current 'dry' list of guidelines.

best wishes

jonathan chetwynd
IT teacher (LDD)
http://www.peepo.com         "The first and still the best picture directory
on the web"
Received on Monday, 20 August 2001 02:44:29 UTC

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