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From: "Reinhard Boerger" <Reinhard.Boerger@FernUni-Hagen.de>
To: "'Ellis D. Cooper'" <xtalv1@netropolis.net>, <categories@mta.ca>
Subject: Re: Fundamental Theorem of Category Theory?
Date: Wed, 17 Jun 2009 09:29:46 +0200	[thread overview]
Message-ID: <E1MGv5P-0000Jp-Qa@mailserv.mta.ca> (raw)

Dear all,

I strongly agree to Ellis Gould's quote of Bill Lawvere's remark on the
Yoneda Lemma:

> -- a mathematical theory corresponds "roughly to
> the definition of a class
> of mathematical objects"

One of the most important points in category theory are universal
properties. The existence of universal solutions is equivalent to the
representability of certain functors - at least under reasonable smallness
conditions. This is closely related to the Yoneda Lemma; therefore it is
really one of the fundamental theorems to me.


Greetinge
Reinhard



[For admin and other information see: http://www.mta.ca/~cat-dist/ ]


             reply	other threads:[~2009-06-17  7:29 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-06-17  7:29 Reinhard Boerger [this message]
  -- strict thread matches above, loose matches on Subject: below --
2009-06-22 12:31 claudio pisani
2009-06-19 19:46 Matsuoka Takuo
2009-06-18  8:33 Vaughan Pratt
2009-06-18  0:27 Matsuoka Takuo
2009-06-17 22:45 Steve Lack
2009-06-17 17:04 Fred E.J. Linton
2009-06-17  3:28 Vaughan Pratt
2009-06-16 21:58 Steve Lack
2009-06-16 20:23 Ellis D. Cooper
2009-06-16 19:34 Prof. Peter Johnstone
2009-06-15 22:02 Ellis D. Cooper
2009-06-15 21:58 Vaughan Pratt
2009-06-14 15:08 Makoto Hamana
2009-06-10  2:29 Hasse Riemann
2009-06-08 20:33 Miles Gould
2009-06-08 11:44 tholen
2009-06-07  1:09 Fred E.J. Linton
2009-06-05 20:36 Ellis D. Cooper

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