From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/6736 Path: news.gmane.org!not-for-mail From: William Messing Newsgroups: gmane.science.mathematics.categories Subject: Re: size_question_reloaded Date: Mon, 04 Jul 2011 08:11:04 -0500 Message-ID: References: Reply-To: William Messing NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: quoted-printable X-Trace: dough.gmane.org 1309969379 7356 80.91.229.12 (6 Jul 2011 16:22:59 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Wed, 6 Jul 2011 16:22:59 +0000 (UTC) Cc: Categories list To: "Eduardo J. Dubuc" Original-X-From: majordomo@mlist.mta.ca Wed Jul 06 18:22:54 2011 Return-path: Envelope-to: gsmc-categories@m.gmane.org Original-Received: from smtpx.mta.ca ([138.73.1.30]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1QeUsF-0006G2-PF for gsmc-categories@m.gmane.org; Wed, 06 Jul 2011 18:22:51 +0200 Original-Received: from mlist.mta.ca ([138.73.1.63]:40550) by smtpx.mta.ca with esmtp (Exim 4.71) (envelope-from ) id 1QeUpv-0004tn-0g; Wed, 06 Jul 2011 13:20:27 -0300 Original-Received: from majordomo by mlist.mta.ca with local (Exim 4.71) (envelope-from ) id 1QeUpu-0005Or-9v for categories-list@mlist.mta.ca; Wed, 06 Jul 2011 13:20:26 -0300 In-Reply-To: Precedence: bulk Xref: news.gmane.org gmane.science.mathematics.categories:6736 Archived-At: Concerning Eduardo's question: Now, if you work with a Grothendieck=20 base topos =93as if it were the category of sets=94, you are forced to=20 specify which small category of finite sets you are using, or not ?. No, in the definition of an U-topos, E, given in SGA 4, Expose IV, =A7 1= ,=20 it is required that E has an U-small (topologically) generating set of=20 objects. Bu such a set or, equivalently, full subcategory of E, is not=20 part of the data. Bill Messing [For admin and other information see: http://www.mta.ca/~cat-dist/ ]