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From: "mail.btinternet.com" <ronnie.profbrown@btinternet.com>
To: "catbb" <categories@mta.ca>
Subject: Re: terminology in definitions of limits
Date: Thu, 22 Jan 2009 11:16:38 -0000	[thread overview]
Message-ID: <E1LQBgE-0002NU-Mi@mailserv.mta.ca> (raw)

Without getting into discussion of the `game' aspect, I feel category
theorists should speak out against the epsilon-delta approach to limits as
against the neighbourhood
                       f(M) \subseteq N
approach, where the notation easily describes  the pictures. The
epsilon-delta approach is in terms of measurement of a neighbourhood, i.e.
one step away from the neighbourhood, and less actual (I almost wrote
`real'!), and students find that step difficult.  The utility of
epsilon-delta is in terms of calculation, rather than geometry and
structure.

The  `only measurable things are real' approach is based on the notion that
numbers are the most important aspect of science, rather than one tool to
investigate  structure.

Ronnie





             reply	other threads:[~2009-01-22 11:16 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-01-22 11:16 mail.btinternet.com [this message]
  -- strict thread matches above, loose matches on Subject: below --
2009-01-22 12:07 Eduardo J. Dubuc
2009-01-22 11:17 Richard Garner
2009-01-22  1:47 Michael Barr
2009-01-21 18:01 John Baez
2009-01-21 16:48 Charles Wells
2009-01-21  7:34 Vaughan Pratt
2009-01-20 17:15 Colin McLarty
2009-01-20 16:39 Paul Taylor
2009-01-19 18:13 peasthope

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