From: pare@mathstat.dal.ca (Robert Pare)
To: categories@mta.ca
Subject: Canonical quotients
Date: Sun, 12 Sep 2010 09:04:38 -0300 (ADT) [thread overview]
Message-ID: <20100912120438.14DF55C186@chase.mathstat.dal.ca> (raw)
Peter Freyd's and John Kennison's examples definitively settled
Mike Barr's question about canonical subobjects that compose. But
I had started thinking about it and had what I thought would be a
nice example. The category of sets has canonical quotients (equivalence
classes) but they don't compose. I think there is no choice that do,
but so far I haven't been able to prove or disprove this. Anybody?
Bob
[For admin and other information see: http://www.mta.ca/~cat-dist/ ]
next reply other threads:[~2010-09-12 12:04 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-09-12 12:04 Robert Pare [this message]
2010-09-12 21:18 ` Thorsten Palm
2010-09-13 18:56 ` Michael Barr
2010-09-13 14:09 Peter Selinger
2010-09-14 15:06 Thorsten Palm
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