Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail From: Moebius Newsgroups: sci.math Subject: Re: Incompleteness of Cantor's enumeration of the rational numbers (extra-ordinary) Date: Fri, 10 Jan 2025 03:01:10 +0100 Organization: A noiseless patient Spider Lines: 45 Message-ID: References: <53d93728-3442-4198-be92-5c9abe8a0a72@att.net> <9c18a839-9ab4-4778-84f2-481c77444254@att.net> <8ef20494f573dc131234363177017bf9d6b647ee@i2pn2.org> <66868399-5c4b-4816-9a0c-369aaa824553@att.net> <417ff6da-86ee-4b3a-b07a-9c6a8eb31368@att.net> <07258ab9-eee1-4aae-902a-ba39247d5942@att.net> Reply-To: invalid@example.invalid MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Injection-Date: Fri, 10 Jan 2025 03:01:10 +0100 (CET) Injection-Info: dont-email.me; posting-host="e55a72decad5857fdf1d7f2890a6564b"; logging-data="3816152"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX19/SQLacmYRD15rnD7BZ3B0" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:SSOyAoyy7tkzIxRBIas9P/TUlZ4= Content-Language: de-DE In-Reply-To: Bytes: 3446 Am 10.01.2025 um 02:48 schrieb Moebius: > Am 10.01.2025 um 02:45 schrieb Moebius: >> Am 10.01.2025 um 02:19 schrieb Chris M. Thomasson: >>> On 1/9/2025 5:15 PM, Moebius wrote: >>>> Am 09.01.2025 um 22:12 schrieb Chris M. Thomasson: >>>>> On 1/9/2025 8:18 AM, WM wrote: >>>>>> On 09.01.2025 10:56, FromTheRafters wrote: >>>>>>> WM explained : >>>>>> >>>>>>>> The set {1, 2, 3, ...} is smaller by one element than the set >>>>>>>> {0, 1, 2, 3, ...}. >>>>>>> >>>>>>> Both sets are equal in size >>>>>> >>>>>> No. Both sets appear equal (although everybody can see that they >>>>>> are not) when measured by an insufficient tool. > > Hint: WM here meant (of course): "Both sets appear equal IN SIZE ..." Hint@WM: The size of {1, 2, 3, ...} EQUALS the size of {0, 1, 2, 3, ...} when "measured" by the "tool" /equivalence/. See: https://www.britannica.com/science/set-theory/Equivalent-sets ____________________________________________________________________ Hint: Using Zermelo's definition of the natural numbers we have 1 = {0}, 2 = {1}, 3 = {2}, 4 = {3}, ... And hence {1, 2, 3, 4, ...} = {{0}, {1}, {2}, {3}, ...} If we NOW compare {{0}, {1}, {2}, {3}, ...} (= {1, 2, 3, 4, ...}) with { 0 , 1 , 2 , 3 , ...} , does ist STILL make sense to claim "everybody can see that they are not equal in size"? > . > . > . >