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Path: ...!Xl.tags.giganews.com!local-2.nntp.ord.giganews.com!news.giganews.com.POSTED!not-for-mail NNTP-Posting-Date: Thu, 05 Sep 2024 19:57:34 +0000 Subject: Re: Replacement of Cardinality (infinite middle) Newsgroups: sci.logic,sci.math References: <hsRF8g6ZiIZRPFaWbZaL2jR1IiU@jntp> <wdScnSnh-eTlnyH7nZ2dnZfqn_qdnZ2d@giganews.com> <58c50fcb-41ea-4ac3-9791-81dafd4b7a59@att.net> <Z1qdnZK14ptcl137nZ2dnZfqn_ednZ2d@giganews.com> <29fc2200-8ddc-43fe-9130-ea49301d3c5d@att.net> <bKGdnSJUP5vzn1_7nZ2dnZfqnPWdnZ2d@giganews.com> <1c5a8e0d-db33-4254-b456-8bb8e266c295@att.net> <wFadnSzMD4-A-1_7nZ2dnZfqnPqdnZ2d@giganews.com> <fe1ff590-228e-4162-b59d-5e66fadedfef@att.net> <jWSdneBt4MAqAV77nZ2dnZfqn_udnZ2d@giganews.com> <nP-dnd-rxey3Z037nZ2dnZfqnPednZ2d@giganews.com> <ca4ff00c-5652-4a98-a8b3-1c2df29371b6@att.net> <Ozqdna0HeI3Rk0z7nZ2dnZfqn_GdnZ2d@giganews.com> <i5KcnV8Iaeagj0z7nZ2dnZfqn_GdnZ2d@giganews.com> <822a53d2-7503-47d6-b632-6ebaa3ca4a92@att.net> <BOydnXx-lv9FuU_7nZ2dnZfqnPudnZ2d@giganews.com> <97d738be-af48-4e3c-b107-d49f4053f9eb@att.net> <L5adnfZdJdKXK0n7nZ2dnZfqn_qdnZ2d@giganews.com> <ee965bbc-311a-492b-a3f4-93ef249a5ef6@att.net> <5-ScnQ9Ks5z8ykv7nZ2dnZfqn_SdnZ2d@giganews.com> <884e5b13-5d91-4430-ba18-5f4208e283f2@att.net> From: Ross Finlayson <ross.a.finlayson@gmail.com> Date: Thu, 5 Sep 2024 12:57:26 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <884e5b13-5d91-4430-ba18-5f4208e283f2@att.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Message-ID: <JtGdnY-GeMGzkEf7nZ2dnZfqnPSdnZ2d@giganews.com> Lines: 142 X-Usenet-Provider: http://www.giganews.com X-Trace: sv3-ZJnjoBfbpePdTBRYlyc1dO4ObF0t7PjLr1/ZU30YLzXVF6wYJ/fYep2OoQ+RxyrNSCJxBJa0gJUdxLz!g8X0spnjUa2cxiAy6VBBE11orEzW7aFLCJspzI1WnrykTDoXw7CcTGjcZLP2CDTpWcuyvagMxhvj!WQ== X-Complaints-To: abuse@giganews.com X-DMCA-Notifications: http://www.giganews.com/info/dmca.html X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 Bytes: 7537 On 09/03/2024 01:50 PM, Jim Burns wrote: > On 9/2/2024 8:25 PM, Ross Finlayson wrote: >> On 09/02/2024 02:46 PM, Jim Burns wrote: >>> On 9/1/2024 2:44 PM, Ross Finlayson wrote: > >>>> Then the point that induction lets out is >>>> at the Sorites or heap, >>>> for that Burns' "not.first.false", means >>>> "never failing induction first thus >>>> being disqualified arbitrarily forever", >>> >>> Not.first.false is about formulas which >>> are not necessarily about induction. >>> >>> A first.false formula is false _and_ >>> all (of these totally ordered formulas) >>> preceding formulas are true. >>> >>> A not.first.false formula is not.that. >>> >>> not.first.false Fₖ ⇔ >>> ¬(¬Fₖ ∧ ∀j<k:Fⱼ) ⇔ >>> Fₖ ∨ ∃j<k:¬Fⱼ ⇔ >>> ∀j<k:Fⱼ ⇒ Fₖ >>> >>> A finite formula.sequence S = {Fᵢ:i∈⟨1…n⟩} has >>> a possibly.empty sub.sequence {Fᵢ:i∈⟨1…n⟩∧¬Fᵢ} >>> of false formulas. >>> >>> If {Fᵢ:i∈⟨1…n⟩∧¬Fᵢ} is not empty, >>> it holds a first false formula, >>> because {Fᵢ:i∈⟨1…n⟩} is finite. >>> >>> If each Fₖ ∈ {Fᵢ:i∈⟨1…n⟩} is not.first.false, >>> {Fᵢ:i∈⟨1…n⟩∧¬Fᵢ} does not hold a first.false, and >>> {Fᵢ:i∈⟨1…n⟩∧¬Fᵢ} is empty, and >>> each formula in {Fᵢ:i∈⟨1…n⟩} is true. >>> >>> And that is why I go on about not.first.false. > >> Then about not.first.false >> thanks for writing that up a bit more, >> then that also you can see what I make of it. > > What I find poetic about not.first.false and all that > is that our finiteness isn't only _permitted_ > It is _incorporated into_ our logic. _Required_ > > A finite linear order _must be_ well.ordered > (must be, both ways) > ∀γ:T(γ) ⇐ ∀β:(T(β) ⇐ ∀α<β:T(α)) > ∀α:T(α) ⇐ ∀β:(T(β) ⇐ ∀γ>β:T(γ)) > > We are finite. > The formulas we write are finitely.many. > In a linear order, they must be in a well.order. > > In a well.order, > if each formula Φ[β] is not.first.false > ∀β:¬(¬T(Φ[β] ∧ ∀α<β:T(Φ[α]) > ∀β:(T(Φ[β]) ⇐ ∀α<β:T(Φ[α])) > then each formula is not.false. > ∀γ:T(Φ[γ]) > > ...because well.order (because finite). > ∀γ:T(Φ[γ]) ⇐ ∀β:(T(Φ[β]) ⇐ ∀α<β:T(Φ[α])) > >> Not.ultimately.untrue, ..., has that >> F, bears the value for all F_alpha parameterized by ordinals >> (which suffice, large enough, to totally order things), >> of true, and that, >> there are classes of formulas F, >> for example self-referential or differential formulas, >> defined for example according to >> "when F_alpha is not also as for an ordinal less than omega", >> at least making a trivial clear example of >> a definition that is for classes of these sorts formulas >> where "not.ultimately.untrue" is not held by all classes >> for formulas "not.first.false". > > "Not.ultimately.untrue" sounds to me vaguely like "ω-consistent". > But I don't really know what you are talking about. > I usually don't know what you are talking about. > It is what it is. > > That "points do not make lines" and "lines do not make points" yet "any two points define a line" and "any two intersecting lines define a point", are of course quite fundamental and elementary since for most of time that Euclid's Elements is the second-most published book in the world. (Euclid is a panel.) https://en.wikipedia.org/wiki/Transfer_principle I have pretty much no use for the hyper-reals as merely a "conservative" (i.e., saying nothing) extension of the usual Archimedean field, while, something like Nelson's Internal Set Theory and that it's co-consistent with ZFC, with regards to either "both or neither", much like the "both or neither" of "the anti-diagonal and the only-diagonal", have that there are "conservative non-standard" extensions saying _nothing_ and "non-conservative non-standard" extensions saying _something_. When Hilbert _added_ a postulate of continuity to Euclid's axioms, so to establish that a point-set topology could be a thing at all, it's quite a non-conservative non-standard axiom, as it were, itself, though of course for "axiomless geometry" it already exists from there being a prototype continuum as elementary in a theory, co-consistent this theory of geometry "points and spaces" with the usual theory of words (algebra's, set theory's, ...), that, more-than-less you might as well start reading the most-published book in the world, or just the first few items "in the beginning ..." there was space then from the middle "in the beginning ..." there was the word, of an example of a necessary sort of ontological commitment with regards to nominalism, and its weaker forms fictionalism, fallibilism, and anti-realism. I.e., as a strong mathematical platonist with a stronger logicist positivism, my model philosopher's model physicist's model philosophy's model physics, easily encompasses the tiny, weaker, hereditarily-finite fragment what's conservative off ZFC. https://en.wikipedia.org/wiki/Eleatics "The Eleatics have traditionally been seen as advocating a strict metaphysical view of monism in response to the materialist monism advocated by their predecessors, the Ionian school." It certainly is what it is, ....