Path: ...!weretis.net!feeder9.news.weretis.net!i2pn.org!i2pn2.org!.POSTED!not-for-mail From: joes Newsgroups: sci.math Subject: Re: The set of necessary FISONs Date: Sun, 16 Feb 2025 12:11:05 -0000 (UTC) Organization: i2pn2 (i2pn.org) Message-ID: References: <79920977-902d-4f59-a11c-497383221c82@att.net> <468b9c37-ba93-485c-8685-4b320e168251@att.net> <68bab5c2-50d3-43fc-be0d-51e01c5952bb@att.net> <1e5cb0d4-f447-4fa7-b1e9-8056b03d27a2@att.net> <8a4c44c4ba0d3260a90d463acfa814fbc83f557a@i2pn2.org> <853f9685ed5be27fedb6486ca2931ef189b920df@i2pn2.org> <5aefc0d0b454a230e721a8cdb8400cb25ea9a8c1@i2pn2.org> <340761ab1ceb68741d949331a0c64a3d6d5fa237@i2pn2.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Injection-Date: Sun, 16 Feb 2025 12:11:05 -0000 (UTC) Injection-Info: i2pn2.org; logging-data="300144"; mail-complaints-to="usenet@i2pn2.org"; posting-account="nS1KMHaUuWOnF/ukOJzx6Ssd8y16q9UPs1GZ+I3D0CM"; User-Agent: Pan/0.145 (Duplicitous mercenary valetism; d7e168a git.gnome.org/pan2) X-Spam-Checker-Version: SpamAssassin 4.0.0 Bytes: 3171 Lines: 25 Am Sun, 16 Feb 2025 11:39:45 +0100 schrieb WM: > Am Sat, 15 Feb 2025 17:54:05 +0000 schrieb joes: >> Am Sat, 15 Feb 2025 12:50:40 +0100 schrieb WM: >>> On 14.02.2025 19:02, Richard Damon wrote: >>>> On 2/14/25 11:28 AM, WM wrote: >>> >>>>> The definition is that it is a set of FISONs which has a smallest >>>>> element that is not as useless as a cup of coffee. >>>> Which, as I said, is a definition in Naive Set theory, >>> Obviously you have no clue of set theory, be it naive or advanced. >>> Every set of ordinals has a smallest element. Look up the notion of >>> well-order. >> No, that is not the definition. No element of the set of FISONs is >> necessary > Therefore all can be removed, and U(F) = ℕ ==> U(F\F) = ℕ. No, obviously you can’t remove all („which one is necessary?” my ass). That the union of the empty set is not N has no bearing on the matter. >> (though one could be, if we wouldn’t agree that none is) >> for their union to be N. *That* set has a smallest element, as does >> every other infinite set of FISONs (the nonempty finite sets do as >> well, but their union is not N, but the largest FISON). Now you come >> along and claim that the empty set should have a first element. -- Am Sat, 20 Jul 2024 12:35:31 +0000 schrieb WM in sci.math: It is not guaranteed that n+1 exists for every n.