Path: ...!Xl.tags.giganews.com!local-3.nntp.ord.giganews.com!news.giganews.com.POSTED!not-for-mail NNTP-Posting-Date: Mon, 30 Dec 2024 01:17:51 +0000 Subject: Re: Incompleteness of Cantor's enumeration of the rational numbers (extra-ordinary) Newsgroups: sci.math References: <069069bf23698c157ddfd9b62b9b2f632b484c40@i2pn2.org> <2d3620a6e2a8a57d9db7a33c9d476fe03cac455b@i2pn2.org> <75921cc1f17cdb691969a99e666f237cd09c0b09@i2pn2.org> <25729298b142c60d5b245231984119d42d4ac089@i2pn2.org> <8a5ea464a97000a9e3e8cad62bd9d2a0f5aa5742@i2pn2.org> <4z6dnRakN8kgDOz6nZ2dnZfqn_sAAAAA@giganews.com> <727cd9d4-df50-4a44-8529-cfc5dfb39bcb@att.net> From: Ross Finlayson Date: Sun, 29 Dec 2024 17:17:45 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Message-ID: Lines: 39 X-Usenet-Provider: http://www.giganews.com X-Trace: sv3-9Bs9AyGkj8gzRuASPDq+yA8NhxetdIcswuEMtOINkXk7/50T5LkftSSOV8cXMeabKawjqPCCYXFYa5V!LShkPLpQfddUDkhBAcqo8oIv11wjd7tP3EF/C/6EBeCj+WFjYP8Uh4lHs4GsfEd1MxuUObUY1Ws= X-Complaints-To: abuse@giganews.com X-DMCA-Notifications: http://www.giganews.com/info/dmca.html X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 Bytes: 3209 On 12/29/2024 01:48 PM, Jim Burns wrote: > On 12/29/2024 3:57 PM, Ross Finlayson wrote: >> On 12/29/2024 12:34 PM, Jim Burns wrote: >>> On 12/29/2024 1:15 PM, Ross Finlayson wrote: >>>> On 12/29/2024 06:43 AM, joes wrote: > >>>>> The infinite union doesn’t. >>>> >>>> There is no "infinite union" in ZF, >>>> only "pair-wise union", >>>> according to the axiom of union. >>> >>> No. >>> https://en.wikipedia.org/wiki/Axiom_of_union >>> ⎛ Informally, the axiom states that >>> ⎜ for each set x there is a set y >>> ⎜ whose elements are precisely >>> ⎝ the elements of the elements of x. >> >> "In-formally [naively], ...." > > 'Informally' isn't 'naively'. > > ⎛ In the formal language of the Zermelo–Fraenkel axioms, > ⎜ the axiom reads: > ⎝ ∀A∃B∀c(c∈B⟺∃D(c∈D∧D∈A)) > -- ibid. > > Yeah, "pair-wise". I'm telling you, I am not wrong, and for a long time, I am not under-informed, about ZF and ZFC set theories. Mistakes to the contrary are wrong and/or under-informed.