On Saturday, 23 March 2019 11:14:41 UTC-6, Khong Dong wrote:
> On Saturday, 23 March 2019 10:53:05 UTC-6, Khong Dong wrote:
> > On Saturday, 23 March 2019 10:24:34 UTC-6, Khong Dong wrote:
> > > On Saturday, 23 March 2019 09:26:31 UTC-6, Khong Dong wrote:
> > > > On Saturday, 23 March 2019 04:45:46 UTC-6, Rupert wrote:
> > > > > On Saturday, March 23, 2019 at 12:05:57 AM UTC+1, Khong Dong wrote:
> > > > > > On Friday, 22 March 2019 15:22:22 UTC-6, Rupert wrote:
> > > > > > > On Friday, March 22, 2019 at 4:47:27 PM UTC+1, Khong Dong wrote:
> > > > > > > > On Friday, 22 March 2019 08:56:42 UTC-6, Rupert wrote:
> > > > > > > > > On Friday, March 22, 2019 at 3:47:48 PM UTC+1, Khong Dong wrote:
> > > > > > > > > > On Friday, 22 March 2019 08:41:33 UTC-6, Rupert wrote:
> > > > > > > > > > > On Friday, March 22, 2019 at 6:02:48 AM UTC+1, Khong Dong wrote:
> > > > > > > > > > > > On Thursday, 21 March 2019 20:35:22 UTC-6, Rupert wrote:
> > > > > > > > > > > > > On Friday, March 22, 2019 at 3:18:56 AM UTC+1, Khong Dong wrote:
> > > > > > > > > > > > > > On Thursday, 21 March 2019 04:22:16 UTC-6, Rupert wrote:
> > > > > > > > > > > > > > > On Thursday, March 21, 2019 at 7:49:07 AM UTC+1, Khong Dong wrote:
> > > > > > > > > > > > > > > > Not 100% sure why I ping you - "Me" - perhaps partially because it strikes
> > > > > > > > > > > > > > > > me that you're technical, objective, deliberate, fair poster, in evaluating
> > > > > > > > > > > > > > > > technical matters, or perhaps because it's a shot in the dark I'm trying,
> > > > > > > > > > > > > > > > or perhaps because you said in the other thread:
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > "It's well known that we have to be careful if dealing with the notion
> > > > > > > > > > > > > > > > of /infinity/".
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > but whatever the reasons, I'm just wondering if you could comment on the
> > > > > > > > > > > > > > > > technical correctness of the three meta theorems below (which I posted in
> > > > > > > > > > > > > > > > MO last month or so) - basically proving it's logically impossible (there
> > > > > > > > > > > > > > > > being no meta proofs) to know, verify the truth value of:
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > cGC <-> "There being infinitely counter examples of Goldbach Conjecture".
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > Certainly the presentation isn't perfect given it's as long as only one post
> > > > > > > > > > > > > > > > but I'll try my best to answer any question you might have.
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > Thank you in advance,
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > Best Regards,
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > -Nam Nguyen
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > ===========================================================================
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > ===> Definitions
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > GC <-> Goldbach Conjecture
> > > > > > > > > > > > > > > > cGC <-> "There are infinitely many counter examples of Goldbach Conjecture"
> > > > > > > > > > > > > > > > SR <->(~GC /\ ~cGC)
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > knowable(S) <=> There's a FINITE meta mathematical proof that S is (non-vacuously) true.
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > undecidable(S) <=> neg(knowable(S)) and neg(knowable(neg(S))).
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > Caveat: This is meta level truth-"undecidable", _not_ FOL provability-"undecidable".
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > intrinsic(S) <=> TRUE(S), for all the meaning of S.
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > ===> Assumptions
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > The definition of prime(p)is free of occurrences of the language constant successor function symbol - required for any proof by induction:
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > prime(p)<->((~p=0)/\~Az[p*z=z]/\((p=x*y)->(Az[x*z=z]\/Az[y*z=z])))
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > Let's let U be the set of Von Neumann's (or Zermelo's) finite ordinals, or some kind of (infinite) union between the two sets.
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > There exists an uncountable set K of language structures M's having these following properties:
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > 1. All M's have the same domain - the universe of discourse U, mentioned
> > > > > > > > > > > > > > > > above.
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > 2. A natural number n is interpreted by a term of the language - a numeral -
> > > > > > > > > > > > > > > > denoting an element e_n in U but is neither the element nor the term
> > > > > > > > > > > > > > > > (numeral)!
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > For the economy of typing, we might conveniently use natural numbers and
> > > > > > > > > > > > > > > > elements interchangeably but that does *not* take away the said
> > > > > > > > > > > > > > > > distinction.
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > 3. The truth of a formula F in any of them can also be interpreted the truth
> > > > > > > > > > > > > > > > of F of (about) the natural numbers.
> > > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > > 4. Any element in U that is interpreted as a non-odd prime natural number n
> > > > > > > > > > > > > > > > in any of the structures is interpreted as the same non-odd prime natural
> > > > > > > > > > > > > > > > number n in all of the structures.
> > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > I have a question about this.
> > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > You're talking about an infinite family of structures for the first-order language of arithmetic, right, all of them with the same domain of discourse U. Where U, if I understand correctly, is some fixed infinite subset of the union of the set of all finite von Neumann ordinals and the set of all
> > > > > > > > > > > > > > > finite Zermelo ordinals.
> > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > And I assume "non-odd prime natural number n" means, a natural number n
> > > > > > > > > > > > > > > which is not an odd prime number.
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > It means the natural number n here is either, Zero, One, Two, or a multiple.
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > So, what exactly does it mean to say that an element of U is interpreted
> > > > > > > > > > > > > > > as a natural number n in one of the structures? That means that, in that
> > > > > > > > > > > > > > > structure, the referent of the numeral for n is equal to the element of U
> > > > > > > > > > > > > > > in question, does it?
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > Right. It means exactly as Assumption 2 states:
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > <quote>
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > 2. A natural number n is interpreted by a term of the language - a numeral -
> > > > > > > > > > > > > > denoting an element e_n in U but is neither the element nor the term
> > > > > > > > > > > > > > (numeral)!
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > </quote>
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > It goes without saying that, in general, each different M in K would induce
> > > > > > > > > > > > > > a different interpretation on the individual element e_n in U.
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > > Also later on with your statement of Lemma 1.
> > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > "Lemma 1: If p is a variable denoting an odd prime (element) in M, the
> > > > > > > > > > > > > > > uniqueness of the numeral of p - numeral(p) - is unknown."
> > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > So M is one of the structures in the collection, right? Now, are you
> > > > > > > > > > > > > > > assuming that every element of U is the referent of a numeral relative to
> > > > > > > > > > > > > > > M?
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > Correct. For instance, the Zermelo element z_3 = {{{{}}} could be a referent
> > > > > > > > > > > > > > for the (prime) numeral SSSS0 for some M but could also be a referent for
> > > > > > > > > > > > > > the (prime) numeral SSSSSS0 for some different M'.
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > > And what does it mean to say the uniqueness of the numeral of p is
> > > > > > > > > > > > > > > unknown?
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > Because there's an 1-many relationship between an element e_n and the
> > > > > > > > > > > > > > numerals relative to which M of K we choose: in the example above you have
> > > > > > > > > > > > > > the element z_3 but it's invalid to say its numeral must necessarily be
> > > > > > > > > > > > > > SSSS0, or SSSSSS0, ... _without referring to a *particular* M_ in K.
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > > What if I stipulate that the numeral of p is SSSSS0? Then surely I know
> > > > > > > > > > > > > > > the numeral of p, and that seems to be consistent with the hypotheses
> > > > > > > > > > > > > > > of your lemma. So what can this lemma really be saying?
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > Here you've involved another issue: p as stated in Lemma 1 is a free
> > > > > > > > > > > > > > _free variable term of the language_ and all you'd know (would be given in
> > > > > > > > > > > > > > the Lemma) is that p is an odd prime element: but you can't sufficiently
> > > > > > > > > > > > > > know the specificity of M.
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > If you stipulate that the numeral of p be the particular numeral SSSSS0 then
> > > > > > > > > > > > > > you've sufficiently specified the underlying M, and in that case p as an
> > > > > > > > > > > > > > element (or as denoting an element) would have to be (or refer to) a
> > > > > > > > > > > > > > specific element. Iow, p would no longer be a free variable that Lemma 1 is
> > > > > > > > > > > > > > talking about: it'd be a language-defined symbol for an individual constant
> > > > > > > > > > > > > > element, a syntactical alias for SSSSS0.
> > > > > > > > > > > > >
> > > > > > > > > > > > > Okay. Well, I wouldn't mind seeing the proof of Lemma 2 then.
> > > > > > > > > > > >
> > > > > > > > > > > > Sure. Proof:
> > > > > > > > > > > >
> > > > > > > > > > > > By Assumption 4, in a *general M* of K, the *general* even element e of U,
> > > > > > > > > > > > in Lemma 2, would be interpreted as the same natural even number, say, N_e.
> > > > > > > > > > >
> > > > > > > > > > > I'm sorry, I don't understand this sentence.
> > > > > > > > > >
> > > > > > > > > > Perhaps you could say which part of it that would prevent you? Would you
> > > > > > > > > > understand all the antecedent (required) assumptions (particularly
> > > > > > > > > > Assumption 4) prior to Lemma 2?
> > > > > > > > >
> > > > > > > > > I think the main problem is that your use of the word "general" is unclear.
> > > > > > > >
> > > > > > > > In this context "general" would mean "non specific" or "free" (variable).
> > > > > > >
> > > > > > > I'm afraid that doesn't help me very much.
> > > > > >
> > > > > > Why? You don't know what a free variable means? I could look up Shoenfield's and
> > > > > > explain it for you if you'd like.
> > > > >
> > > > > I know what a free variable is.
> > > > >
> > > > > But that is no particular help in understanding your sentence.
> > > >
> > > > Then I don't think any mathematician or sci.logic poster in the right mind
> > > > would understand what you've complained on Lemma 2:
> > > >
> > > > "Lemma 2: If e is a free variable ranging over the set of even elements
> > > > in U of M, and p is a prime element bounded to e, the uniqueness of
> > > > numeral(p)is unknown."
> > > >
> > > > Rupert:
> > > >
> > > > "Okay. Well, I wouldn't mind seeing the proof of Lemma 2 then."
> > > >
> > > > NN:
> > > >
> > > > "Sure. Proof:
> > > >
> > > > By Assumption 4, in a *general M* of K, the *general* even element e of U,
> > > > in Lemma 2, would be interpreted as the same natural even number, say,
> > > > N_e."
> > > >
> > > > Rupert:
> > > >
> > > > "I'm sorry, I don't understand this sentence."
> > > >
> > > > NN:
> > > >
> > > > "Perhaps you could say which part of it that would prevent you? Would you
> > > > understand all the antecedent (required) assumptions (particularly
> > > > Assumption 4) prior to Lemma 2?"
> > > >
> > > > Rupert:
> > > >
> > > > "I think the main problem is that your use of the word "general" is
> > > > unclear."
> > > >
> > > > NN:
> > > >
> > > > "In this context "general" would mean "non specific" or "free" (variable)."
> > > >
> > > > Rupert:
> > > >
> > > > "I'm afraid that doesn't help me very much."
> > > >
> > > > ====================================================
> > > >
> > > > Your "main problem" in understanding the Lemma 2 proof's is that the proof
> > > > would refer to the variable e (the Lemma 2's "e is a free variable ranging
> > > > over the set of even elements") as a _general_ variable which you complained
> > > >
> > > > <quote>
> > > > the word "general" is unclear
> > > > </quote>
> > > >
> > > > but which I has clearly explained "general" means "free": so you or any
> > > > student can replace e being a "general" even number here by e being a free variable denoting an even element in U in M. It's bizarre that you couldn't
> > > > even understand that much!
> > > >
> > > > So either your complaint:
> > > >
> > > > <quote>
> > > >
> > > > the word "general" is unclear
> > > >
> > > > </quote>
> > > >
> > > > wasn't genuine or for some inexplicable reasons you forgot what a "free" variable would mean!
> > > >
> > > > Btw, Rupert, the below inferrecne :
> > > >
> > > > P(n) -> An[P(n)]
> > > >
> > > > is possible by an inference rule named UG - universal - _GENERALIZATION_ !
> > > >
> > > > Are you going to complaint TOO something like:
> > > >
> > > > "I think the main problem is that the use of the word 'GENERALIZATION'
> > > > here is unclear"
> > > >
> > > > ?
> > >
> > > Anyway, the technical proof for Lemma 2 isn't that convoluted, Rupert.
> > >
> > > Let M, M' be free variables over K. We don't know whether or not M = M' but
> > > we do know by Assumption 4 the successions of even elements in both M and
> > > M' are identical. But by Assumption 5 the same can't be logically said of
> > > the successions of (odd) primes in M and M'.
> > >
> > > That's all Lemma 2 really says.
> >
> > For instance, consider the below Zermelo's elements:
> >
> > Even elements:
> >
> > z_6 = {{{{{{{}}}}}}}
> > z_8 = {{{{{{{{{}}}}}}}}}
> >
> > Prime elements:
> >
> > z_3 = {{{{}}}}
> > z_11 = {{{{{{{{{{{{}}}}}}}}}}}}
> >
> > Your M could have these 2-tuples in the binary relation symbolized by '<':
> >
> > (z_6, z_8), (z_3, z_6), (z_3, z_11), (z_11, z_8), ...
> >
> > But your M' otoh could have:
> >
> > (z_6, z_8), (z_11, z_6), (z_11, z_3), (z_3, z_8), ...
> >
> > Note the identical 2-tuple (z_6, z_8) exists in both cases - but the
> > remaining 2-tuples are different.
> >
> > Incidentally, the numeral for z_3 would be different between M and M', ditto
> > for that of z_11, as implicated in Lemma 2!
> >
> > Hope this has helped clarifying proof of Lemma 2 you've requested.
>
> Note that from Lemma 2, we can show it's invalid to _even assume_
> Shoenfield's N8 [1] be true in any M of K (hence it'd be invalid to assume
> it be true of the natural numbers) - independent of whether or not PA is
> _syntactically_ consistent.
>
> This in effect is one of the gateways into showing Completeness is invalid.
>
> [1]
>
> N8 <-> (x < Sy <-> (x < y \/ x = y))
It's an interesting coincidence (or may be not) that Rupert once said:
"There are mathematical propositions which can neither be proved true
nor proved false."
Shoenfield's N8 seems to fit right in, whether or not Rupert himself
realizes it.