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From: Paul B Levy <P.B.Levy@cs.bham.ac.uk>
To: "categories@mta.ca" <categories@mta.ca>
Subject: free cocompletion
Date: Wed, 11 May 2016 14:08:15 +0100	[thread overview]
Message-ID: <E1b0dG8-0005Li-En@mlist.mta.ca> (raw)

Hi, the following result appears to be folklore:

Given a locally small category C, the full subcategory of [C^op,Set] on
small presheaves (i.e. those presheaves that are colimits of a small
diagram of representables) is a free cocomplete locally small category on C.

I've seen and heard this result in many places, and know how to prove
it, but is there a proof written out in the literature?  And where did
the statement first appear?

Paul



-- 
Paul Blain Levy
School of Computer Science, University of Birmingham
http://www.cs.bham.ac.uk/~pbl


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


             reply	other threads:[~2016-05-11 13:08 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-05-11 13:08 Paul B Levy [this message]
2016-05-12  8:27 ` Tom Hirschowitz
     [not found] <CAK9bN=CFTC3DhitMRrb_9QQFc2atr5UbPcSAMZpC-8X67ypTLQ@mail.gmail.com>
     [not found] ` <CAK9bN=Bdc4nMiKhEE2Nq3FEDYd4RvYuFDdVB238tq-aVY5BfAw@mail.gmail.com>
2016-05-12  7:55   ` Free cocompletion Sam Dean
2016-05-15 15:21 Andree EHRESMANN

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