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From: categories <cat-dist@mta.ca>
To: categories <categories@mta.ca>
Subject: Re: Pratt slices
Date: Wed, 5 Nov 1997 17:33:47 -0400 (AST)	[thread overview]
Message-ID: <Pine.OSF.3.90.971105173329.23856K-100000@mailserv.mta.ca> (raw)

Date: Tue, 04 Nov 1997 11:15:46 -0800
From: Vaughan R. Pratt <pratt@cs.Stanford.EDU>


>From: Dr. P.T. Johnstone <P.T.Johnstone@dpmms.cam.ac.uk>
>So we ought surely to be looking for
>a common generalization, not of toposes and abelian categories, but of
>(pre)toposes and affine categories in Aurelio's sense.

In that context let me rephrase my question about adding in Set\op as,
is the common universal Horn theory of Set, Ab, and Set\op, along with
their slices, finitely axiomatizable?  Or (with or without the slices)
is this nice link between Set and Ab confined to the geometric
(discrete) half of mathematics?

Vaughan



             reply	other threads:[~1997-11-05 21:33 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
1997-11-05 21:33 categories [this message]
  -- strict thread matches above, loose matches on Subject: below --
1997-11-04 17:34 categories

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