From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/5461 Path: news.gmane.org!not-for-mail From: Ross Street Newsgroups: gmane.science.mathematics.categories Subject: Re: Small is beautiful Date: Mon, 4 Jan 2010 08:42:08 +1100 Message-ID: References: Reply-To: Ross Street NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 (Apple Message framework v936) Content-Type: text/plain; charset=ISO-8859-1; format=flowed; delsp=yes Content-Transfer-Encoding: quoted-printable X-Trace: ger.gmane.org 1262574570 23586 80.91.229.12 (4 Jan 2010 03:09:30 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Mon, 4 Jan 2010 03:09:30 +0000 (UTC) To: Vaughan Pratt Original-X-From: categories@mta.ca Mon Jan 04 04:09:22 2010 Return-path: Envelope-to: gsmc-categories@m.gmane.org Original-Received: from mailserv.mta.ca ([138.73.1.1]) by lo.gmane.org with esmtp (Exim 4.50) id 1NRdJq-0006oK-4f for gsmc-categories@m.gmane.org; Mon, 04 Jan 2010 04:09:22 +0100 Original-Received: from Majordom by mailserv.mta.ca with local (Exim 4.61) (envelope-from ) id 1NRctf-0002T0-K1 for categories-list@mta.ca; Sun, 03 Jan 2010 22:42:19 -0400 In-Reply-To: Original-Sender: categories@mta.ca Precedence: bulk Xref: news.gmane.org gmane.science.mathematics.categories:5461 Archived-At: On 03/01/2010, at 6:57 PM, Vaughan Pratt wrote: >> For these, one can't expect the kinds of >> universal constructions that large categories have, > > Not following. FinSet is an essentially small category, what do you > mean that it doesn't enjoy universal constructions? It's even a =20 > topos. Dear Vaughan Part of what Bob Par=E9 was arguing, I believe, was that we should be =20= flexible (pun intended) about what "small" means. If "small" means "finite" =20 then FinSet is not "essentially small". Also, "small" could mean "no more than one =20= element". Ross= [For admin and other information see: http://www.mta.ca/~cat-dist/ ]