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: Sun, 1 Dec 2024 12:17:25 +0200 Organization: - Lines: 28 Message-ID: References: <5b8de1bc-9f6c-4dde-a7cd-9e22e8ce19d9@att.net> <31419fde-62b3-46f3-89f6-a48f1fe82bc0@att.net> <476ae6cb-1116-44b1-843e-4be90d594372@att.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Sun, 01 Dec 2024 11:17:26 +0100 (CET) Injection-Info: dont-email.me; posting-host="bdc9a2c0b734bba0a507d8ea3cf51499"; logging-data="2532852"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1/NkrGShM8xodCw0LzfGA2H" User-Agent: Unison/2.2 Cancel-Lock: sha1:Fs0nuZo5mCq+jX3cEFfeRLiAAYQ= Bytes: 2731 On 2024-11-27 11:10:51 +0000, WM said: > On 27.11.2024 10:33, Mikko wrote: >> On 2024-11-26 11:07:57 +0000, WM said: >> >>> On 26.11.2024 10:09, Mikko wrote: >>>> On 2024-11-25 14:38:13 +0000, WM said: >>> >>>>> The simple example contradicts a bijection between the two sets >>>>> described above. >>>> >>>> What does "contradicts a bijection" mean? >>>> >>> It shows that the mapping claimed to be a bijection is not a bijection. >> >> If so, no bijection is contradicted. > > The possibility of a bijection between the sets ℕ = {1, 2, 3, ...} and > D = {10n | n ∈ ℕ} is contradicted. No, it is not. You merely deny it, disregarding obvious facts. The function f(x) = 10 * f obviously maps every element of ℕ to a different element of D and there is no element of D that is not 10 * f for some f so this f is a bijection between ℕ and D. -- Mikko