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From: FEJ Linton <FLinton@Wesleyan.edu>
To: categories@mta.ca
Subject: Re: The Idea of Structure as Data and Conditions
Date: Mon, 28 May 2012 02:00:12 -0400	[thread overview]
Message-ID: <E1SZ8q4-0004H2-2Y@mlist.mta.ca> (raw)
In-Reply-To: <alpine.LRH.2.02.1205261942060.32490@msr03.math.mcgill.ca>

On Sat, 26 May 2012 19:48:26 -0400 (EDT), Michael Barr wrote:

> Let me point out that not every structure comes with an obvious notion of
> morphism.  --- [examples snipped] ---

The most common example: sets. The structure is based on membership.
Virtually no one ever wants to restrict attention to functions that respect
(preserve or reflect) membership (other than "preserve" between ordinals).

Cheers, -- Fred



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


  parent reply	other threads:[~2012-05-28  6:00 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-05-25 22:09 Ellis D. Cooper
2012-05-26 23:48 ` Michael Barr
2012-05-27 18:16   ` Eduardo J. Dubuc
2012-05-28  6:00   ` FEJ Linton [this message]
2012-05-29 13:28     ` Staffan Angere
2012-05-30  6:26     ` Vaughan Pratt
2012-05-27 13:02 ` Charles Wells
     [not found] ` <CABZOOqZ54NtG1n3K4f8o6mMRSgZ_2yVjE6S+-UWkQSO_PXi1tQ@mail.gmail.com>
2012-05-27 13:06   ` Charles Wells
2012-05-27 23:25 ` Vaughan Pratt
2012-05-29  3:15 Fred E.J. Linton
2012-05-29 13:28 ` Colin McLarty

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