From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/2008 Path: news.gmane.org!not-for-mail From: rosicky@math.muni.cz (Jiri Rosicky) Newsgroups: gmane.science.mathematics.categories Subject: Re: Pro C Date: Fri, 8 Jun 2001 14:37:49 +0200 (CEST) Message-ID: <20010608123749.12BE3836E@queen.math.muni.cz> NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1241018279 1701 80.91.229.2 (29 Apr 2009 15:17:59 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 29 Apr 2009 15:17:59 +0000 (UTC) To: categories@mta.ca Original-X-From: rrosebru@mta.ca Sat Jun 9 05:50:36 2001 -0300 Return-Path: Original-Received: (from Majordom@localhost) by mailserv.mta.ca (8.11.1/8.11.1) id f597bXA00842 for categories-list; Sat, 9 Jun 2001 04:37:33 -0300 (ADT) X-Authentication-Warning: mailserv.mta.ca: Majordom set sender to cat-dist@mta.ca using -f X-Mailer: ELM [version 2.4ME+ PL69 (25)] Original-Sender: cat-dist@mta.ca Precedence: bulk X-Keywords: X-UID: 18 Original-Lines: 12 Xref: news.gmane.org gmane.science.mathematics.categories:2008 Archived-At: < Choice isn't needed: all you need is the result that, for any filtered < category C, there is a directed poset P and a final functor P --> C. < There is a proof of this somewhere in SGA4 (I don't have the reference < to hand), where it is attributed to Pierre Deligne; but I suspect it < may be older than this. < Peter Johnstone The proof is also in my book with Adamek, Locally presentable and accessible categories, Theorem 1.5, Jiri Rosicky