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From: cxm7@po.cwru.edu (Colin McLarty)
To: categories@mta.ca
Subject: RE: Mac Lane's inclusions
Date: Mon, 19 Jul 1999 15:45:29 -0400 (EDT)	[thread overview]
Message-ID: <199907191945.PAA22541@babar.INS.CWRU.Edu> (raw)


Robert W. McGrail wrote:

>Correct me if I am wrong, but it seems to me that every \tau-category is a 
>category with inclusions.  Moreover, I recall a result by Freyd that every 
>(sufficiently small? cartesian?) category is equivalent to a \tau-category. 
> The proof does not use choice.

        There is certainly a similarity. Tau categories are cartesian
categories (categories with all finite limits) which not only have selected
monics but also selected jointly-monic n-tuples for all finite n; and all
these things compose. Freyd shows every cartesian category is equivalent to
a tau category.

        My construction seems very like Peter's but shortened by working
only on monics and not jointly monic lists, and never using limits.  

best, Colin





             reply	other threads:[~1999-07-19 19:45 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
1999-07-19 19:45 Colin McLarty [this message]
  -- strict thread matches above, loose matches on Subject: below --
1999-07-17  4:11 Robert W. McGrail
1999-07-15 17:32 Colin McLarty

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