From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/4907 Path: news.gmane.org!not-for-mail From: Uwe.Wolter@ii.uib.no Newsgroups: gmane.science.mathematics.categories Subject: Re: patenting colimits? Date: Thu, 28 May 2009 17:49:40 +0200 Message-ID: Reply-To: Uwe.Wolter@ii.uib.no NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain;charset=ISO-8859-1;DelSp="Yes";format="flowed" Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1243560829 17045 80.91.229.12 (29 May 2009 01:33:49 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Fri, 29 May 2009 01:33:49 +0000 (UTC) To: Steve Vickers , categories@mta.ca Original-X-From: categories@mta.ca Fri May 29 03:33:46 2009 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 1M9qyg-000775-IG for gsmc-categories@m.gmane.org; Fri, 29 May 2009 03:33:46 +0200 Original-Received: from Majordom by mailserv.mta.ca with local (Exim 4.61) (envelope-from ) id 1M9qOZ-0003An-Fe for categories-list@mta.ca; Thu, 28 May 2009 21:56:27 -0300 Content-Disposition: inline Original-Sender: categories@mta.ca Precedence: bulk Xref: news.gmane.org gmane.science.mathematics.categories:4907 Archived-At: Quoting Steve Vickers : > Toby Bartels wrote: >> ... >> Certainly much of what is in the patent application is obvious, >> but perhaps not all of it; were these diagrams of diagrams a new idea?, >> or was applying them to computer system specifications a new idea?. >> ... > > Dear Toby, > > The idea of treating specifications as colimits is a few decades old > now. Burstall and Goguen used it in their categorical account of their > specification language Clear, with a specification used to construct a > new theory as colimit of others. Yes, Steve! And they coined also the idea of so-called "based objects" that allow to distinguish between parameter specifications and imported specifications once you are going to develop a fully fledged theory of parametrized specifications. Ingo Classen worked out this in more detail in his PhD thesis around 1995 (?) at Technical University Berlin. Best regards Uwe Wolter [For admin and other information see: http://www.mta.ca/~cat-dist/ ]