Path: ...!weretis.net!feeder9.news.weretis.net!news.quux.org!eternal-september.org!feeder2.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: "Chris M. Thomasson" Newsgroups: sci.math Subject: Re: Incompleteness of Cantor's enumeration of the rational numbers Date: Wed, 20 Nov 2024 16:53:11 -0800 Organization: A noiseless patient Spider Lines: 48 Message-ID: References: <87babad37e3024a0fb219567f6fb2b7c46ff5eb7@i2pn2.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Injection-Date: Thu, 21 Nov 2024 01:53:14 +0100 (CET) Injection-Info: dont-email.me; posting-host="d9e58977d2d48dce1140db71cc33613f"; logging-data="368990"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX18wowsIjK2hghF0M3J+GrZMYTA5lVhk4nM=" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:Hf9e6/V9PEr9JNTHEMV/JT1glZU= Content-Language: en-US In-Reply-To: Bytes: 3788 On 11/20/2024 4:08 PM, joes wrote: > Am Wed, 20 Nov 2024 19:42:41 +0100 schrieb WM: >> On 20.11.2024 19:18, joes wrote: >>> Am Wed, 20 Nov 2024 13:04:04 +0100 schrieb WM: >> >>>> Try to count to a natural number that has fewer successors than >>>> predecessors. Impossible. >>> Because there are no such numbers. >> All successors are natural numbers. > So? > >> If all can be counted, then no successors remain. > All at once or every single one? > There are no successors "after" all of the other numbers. > >>>> But set theory claims that all natural numbers can be counted to such >>>> that no successors remain. >>> et your quantifiers in order: >> That is a foolish excuse. > You have shown that you don't understand them. > >>> every single natural number is very clearly finite; >> Every number that can be counted to is finite. > There are countably infinite numbers, but ok. A fun part is that if we artificially restrict ourselves to any real number that is also a natural number, well, they are countable now? Fair enough? All naturals are reals, not all reals are naturals... ;^) > >> But every number that can >> be counted to has more successors than predecessors. > Every number, period. There is no number without successors. > >> Therefore not every number can be counted to. > Well, the ordinal numbers less than epsilon_0 are called countably > infinite. > >>> the cardinal number corresponding to the set of all of them is >>> countably infinite. >> The set of all numbers that can be counted to is finite, namely a >> number that is counted to. This cannot change by counting. > WTF there is no largest number. How do you think counting changes > anything? >