Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Mikko Newsgroups: sci.logic Subject: Re: Incompleteness of Cantor's enumeration of the rational numbers (extra-ordinary) Date: Thu, 12 Dec 2024 19:48:05 +0200 Organization: - Lines: 27 Message-ID: References: <0b1bb1a1-40e3-464f-9e3d-a5ac22dfdc6f@tha.de> <95183b4d9c2e32651963bac79965313ad2bfe7e8@i2pn2.org> <33512b63716ac263c16b7d64cd1d77578c8aea9d@i2pn2.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Thu, 12 Dec 2024 18:48:09 +0100 (CET) Injection-Info: dont-email.me; posting-host="a42be70700ef1372c99d8abee7522b36"; logging-data="3022277"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1/VbS5taJY7bKOVNL9evJv+" User-Agent: Unison/2.2 Cancel-Lock: sha1:mbjQcLtii/6DRwkTXONmx8ZheUw= Bytes: 2812 On 2024-12-11 14:04:30 +0000, WM said: > On 11.12.2024 01:25, Richard Damon wrote: >> WM wrote: >>> On 10.12.2024 13:19, Richard Damon wrote: >>> >>>> >>>> The pairing is between TWO sets, not the members of a set with itself. >>> >>> The pairing is between the elements. Otherwise you could pair R and Q by >>> simply claiming it. >>> "The infinite sequence thus defined has the peculiar property to contain >>> the positive rational numbers completely, and each of them only once at >>> a determined place." [Cantor] Note the numbers, not the set. >> >> TWO different sets, not the elements of a set and some of the elements of >> that same set. > > In mathematics, a set A is Dedekind-infinite (named after the German > mathematician Richard Dedekind) if some proper subset B of A is > equinumerous to A. [Wikipedia]. Do you happen to know any set that is Dedekind-infinite? -- Mikko