From: Tim Little on
On 2010-06-21, Peter Webb <webbfamily(a)DIESPAMDIEoptusnet.com.au> wrote:
> The same algorithm does work for all n. Look at the first n terms to
> n places of accuracy.

Provide computer code, please. Here's the required function
signature: int getDigit(BigInteger n). You get to fill in the
function body.


>> For some fixed M, you could embed M digits of the diagonal into the
>> algorithm, and the algorithm would work for all n < M. But that's not
>> enough: it has to work for all n.
>
> I can in fact compute the nth digit of the anti-diagonal for any n
> by hand.

"By hand" is irrelevant to the definition of a computable real,
especially when your "hand" is connected to "eyes" that have the list
as input. The list is *not* input to the algorithm.


> The same objection could be raised to Cantor's proof; after all, he
> accepts a purportedly infinite list as input to his algorithn as
> well.

Cantor does not claim to be proving existence of any finite algorithm.
You are.


> Or are you saying I have to do this without using the infinite list
> itself?

You may use the infinite list to determine which finite algorithm to
use, but the algorithm must be self-contained and not refer to the
list. The *only* input to the algorithm you select will be a natural
number, which denotes n.


> I note that Cantor's original proof also requires an infinite list
> of Reals, but you seem to have no problem with that.

Indeed I don't. Cantor is not claiming that the antidiagonal is a
computable real, and so finite algorithms are irrelevant.

You *are* claiming that the antidiagonal is a computable real, and so
you must prove the existence of a suitable finite algorithm for the
antidiagonal.


- Tim
From: Tim Little on
On 2010-06-21, Peter Webb <webbfamily(a)DIESPAMDIEoptusnet.com.au> wrote:
> "Tim Little" <tim(a)little-possums.net> wrote in message
>> On 2010-06-21, Peter Webb <webbfamily(a)DIESPAMDIEoptusnet.com.au> wrote:
>>> No, I only need a finite algorithm which will calculate it to n
>>> decimal places with finite input.
>>
>> You have previously stated that you can do this with "about three
>> lines of Java code".
>>
>> Here's your Java method signature: int antidiagonalDigit(BigInteger n).
>>
>> Here are the first twenty digits of the first twenty members of my
>> list:
>>
>> 93525532854532512838
>> 32127313472944276266
>> 70595916184994935423
>> 20733652719572401688
>> 30472031767118774150
>> 47190325821263633948
>> 74236814853458351851
>> 58521903865615844550
>> 91701104659863267390
>> 39510921669610680229
>> 19656091025330568974
>> 49591084533660072011
>> 81683520683673830124
>> 93720622611168810054
>> 50284245443806050152
>> 11702670934156383526
>> 58534679962278312978
>> 68478827933494896765
>> 83579375050000862329
>> 50241229144880453593
>>
>> Now let's see your Java code.
>
> Here is my p-code.

As I suspected, your claim that you could actually do it was pure
puffery, and you probably know as little about programming as you do
about mathematics.


> Take the nth digit of the nth item.

The n'th item of *what*? The list is not a parameter, it is not a
global variable, it is completely out of scope. You fail already.


- Tim
From: Tim Little on
On 2010-06-21, Peter Webb <webbfamily(a)DIESPAMDIEoptusnet.com.au> wrote:
> OK, I have a list of all Reals. Which real is missing?

Denoting your list by L, antidiag(L) is missing. If you *tell* me L,
I can verify that it is missing. Otherwise you'll have to verify it
yourself. Either way, it is missing.


>>> But you have made an excellent point in your example. When Cantor is
>>> confronted with some digit as poorly defined your Chaitan's number
>>> example
>>
>> It's not poorly defined at all; it is precisely defined.
>
> No, its not precisley defined, you can't tell me its value to arbitrary
> accuracy.

It looks like the concept of mathematical definition is also an area
of incompetence for you. Failing that, there really in no point in
continuing any further. Goodbye.


- Tim
From: Newberry on
On Jun 20, 6:43 pm, Virgil <Vir...(a)home.esc> wrote:
> In article
> <b1d23660-1b7a-4682-affa-952cf2d9e...(a)e34g2000pra.googlegroups.com>,
>
>
>
>
>
>  Newberry <newberr...(a)gmail.com> wrote:
> > On Jun 20, 1:18 pm, Virgil <Vir...(a)home.esc> wrote:
> > > In article
> > > <f92c169d-ee85-40c2-aa82-c8bdf06f7...(a)j4g2000yqh.googlegroups.com>,
>
> > > WM <mueck...(a)rz.fh-augsburg.de> wrote:
> > > > On 20 Jun., 17:51, "Jesse F. Hughes" <je...(a)phiwumbda.org> wrote:
>
> > > > > Cantor was this utterly insane freak who chose not to accept Newberry's
> > > > > word for it, and instead *prove* that there was no list of all real
> > > > > numbers. Obviously, his proof is nonsense, because, after all, Newberry
> > > > > said there was no list.
>
> > > > His proof is nonsense because it proves that a countable set, namely
> > > > the set of all reals of a Cantor-list and all diagonal numbers to be
> > > > constructed from it by a given rule an to be added to this list,
> > > > cannot be listed, hence, that this indisputably countable set is
> > > > uncountable.
>
> > > That is a deliberate misrepresentation of the so called "diagonal proof".
>
> > > What that proof (not actually by by Cantor himself) ays is that any
> > > listing of reals is necessarily incomplete because given such a listing
> > > one can always construct a real not listed in it.
>
> > Please CONSTRUCT the anti-diagonal in the space provided below.
>
> > Virgil's anti-diagonal construction
> > BEGIN
>
> It is not mine but Cantor's, though the following notation is mine.
>
> N represents the set of natural numbers.
>
> NxN is the Cartesian product of N with itself with members (m,n) where m
> and n are members of N.
>
> F: NxN --> {0,1} is a list of functions, F(m,--),  from N to {0,1}
> with, for each m in N, F(m,--): n --> F(m,n),  being such a function.
>
> Then the anti-diagonal function g:N --> {0,1} is defined by
> g(n) = 1-F(n,n) in {0,1},
> so that   g(n) <>  F(n,n) for all n,
> and thus g(--) <> F(n,--) for all n..
>
> Note the Cantor himself never published  an anti-diagonal argument for
> the reals themselves, though some of his followers did.
>
> > END

Not sure why you think you had to tell us how the anti-diagonal is
defined. You claimed you could CONSTRUCT it. Please go ahead and do
so.

> > > What Cantor himself proved was that for any list of infinite binary
> > > sequences there are binary sequences not listed in that list.
>
> > > Cantor had previously proved by quite a different method, which WM seems
> > > unable or unwilling to criticize, that the set of reals was not
> > > countable.
>
> > > > Even completely blinded matheologicians should be able, perhaps after
> > > > some contemplation, to recognize that.
>
> > > What completely blinded matheologicians are able, perhaps after
> > > some contemplation,to recognize is that WM is not working in the same
> > > world as mathematicians do.- Hide quoted text -
>
> - Show quoted text -- Hide quoted text -
>
> - Show quoted text -

From: Newberry on
On Jun 20, 7:02 pm, "Jesse F. Hughes" <je...(a)phiwumbda.org> wrote:
> Transfer Principle <lwal...(a)lausd.net> writes:
> > On Jun 20, 8:51 am, "Jesse F. Hughes" <je...(a)phiwumbda.org> wrote:
> >> Newberry <newberr...(a)gmail.com> writes:
> >> > That's right. There is no formula or algorithm to construct the list..
> >> > It means that you would have to flip each and every digit one by one..
> >> > And that is impossible.
> >> Of course, it is perfectly reasonable to accept that there is no such
> >> list, because Newberry says so.  
>
> > Ah, so it's nice to see that Newberry has joined Herc and WM in
> > this ever-growing thread.
>
> Yes, how nice!  Er, how come?  Why do you think this is a nice thing?
>
> Honestly?  It's not that I think it's a bad thing --- though, to be
> honest, I think Newberry's better than the argument he gives here ---
> but why do you think it's a positive development?
>
>
>
> >> Cantor was this utterly insane freak who chose not to accept Newberry's
> >> word for it, and instead *prove* that there was no list of all real
> >> numbers.
>
> > But this proof that there is no list of all real numbers must use
> > the axioms of some _theory_ (such as ZFC) -- a theory which
> > Newberry isn't required to accept just because Hughes says so.
>
> Of course he's not required to accept it.  So?
>
> Nonetheless, it is a *theorem*, namely a theorem of ZF.
>
>
>
> > So Hughes continues to be a Herc-religionist (i.e., a religionist
> > according to Herc), appealing to ZFC to prove Newberry wrong even
> > though there's no reason to assume that Newberry is working in ZFC (or
> > any other theory proving Cantor's Theorem).
>
> If Newberry means that Cantor's Theorem is not a Theorem in some other
> (specified) theory, then, of course, I'd have no opinion at all, until I
> saw the theory.
>
> So, let's ask Newberry!
>
> Newberry, what theory did you have in mind?

What I had in mind is that if you drop the axiom of extent you can
either conclude that there is no such list or that the anti-diagonal
does not exist analogously to the conclusion that the set R = {x | ~(x
in x} does not exist.

BTW, Cantor did not work in ZFC and the argument given by McCullough
appeared to be on the intuitive level rather than in any particular
formal theory.

I will grant you that Zermelo figured how to construct a system where
the diagonal argument goes through and his system is probably
consistent. It is a nonsense nevertheless. All the transfinite set
theory is a completely superfluous metaphysics.

> --
> Jesse F. Hughes
> "I'm not going to forget what I've seen.  I understand the devastation
> requires more than one day's attention."
>  -- G. W. Bush reassures Hurricane Katrina victims.  Two days, minimum.