Drexel dragonThe Math ForumDonate to the Math Forum



Search All of the Math Forum:

Views expressed in these public forums are not endorsed by Drexel University or The Math Forum.


Math Forum » Discussions » sci.math.* » sci.math

Topic: Peer-reviewed arguments against Cantor Diagonalization
Replies: 156   Last Post: Nov 4, 2012 3:01 PM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]
Virgil

Posts: 9,012
Registered: 1/6/11
Re: Peer-reviewed arguments against Cantor Diagonalization
Posted: Nov 4, 2012 2:08 AM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

In article <k7548a$tk8$1@news.albasani.net>,
"Peter Webb" <webbfamilyDIEspamDie@optusnet.com.au> wrote:

> Shmuel (Seymour J.) Metz wrote:
>

> > In <k71vu3$cb7$1@news.albasani.net>, on 11/03/2012
> > at 02:35 AM, "Peter Webb" <webbfamilyDIEspamDie@optusnet.com.au>
> > said:
> >

> > > Obviously they are. Somebody constructs a list of purported Reals,
> >
> > Nobody constructs anything. There is a universal quantifier, that's
> > all.
> >

>
>
> Sorry, but the proof commences with a purported list of all Reals. Look
> at it.


Cantor's own proof definitely does not start by assuming that any list
is complete, or even that it is a list of reals. He merely shows that if
one has any list of binary sequences of m's and w's at all, of any sort,
and then that list is not complete.
>
>

> > > Cantor showed that the Reals are not recursively
> > > enumerable, not that they are uncountable.

> >
> > No, he proved that they are uncountable. Theories like ZFC may not be
> > to your taste,

>
> Ohh no, that's definitely false.


Cantor's first proof showed that any list of reals omitted some reals,
i.e., that any listing of reals was necessarily incomplete.

His second, the diagonal proof, did not even mention reals, but was
later modified by someone else to apply to lists of reals s well.
>
>

> > but Cantor's proof is valid in them and nobody has ever
> > found an inconsistency in them.
> >

>
> The proof we are discussing is not formulated in the language of ZF.
> The equivalent proof in ZF is correct.
>
>
>

> > > The proof actually says that such a list cannot be constructed.
> >
> > No, it proves that such a list does not exist, a stronger result.

>
> By showing any purported list is missing a Real.


Actually by showing that any list of binary sequences is missing some
binary sequences.
>
>

> >
> > > It starts with a hypothetical list that has already been
> > > constructed.

> >
> > It uses a shorthand notation for a longer expression involving
> > universal quantifiers.

>
> That's the source of some of the problem in the proof - it uses a
> shorthand which isn't quite correct and isn't properly explained.
>
> I have no problem with the very similar proof in ZF.

--




Date Subject Author
10/27/12
Read Peer-reviewed arguments against Cantor Diagonalization
JRStern
10/27/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Frederick Williams
10/27/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
JRStern
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Tim Little
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
JRStern
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
J. Antonio Perez M.
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Michael Stemper
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
David C. Ullrich
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
JRStern
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
JRStern
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
David C. Ullrich
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
David C. Ullrich
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
LudovicoVan
10/27/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
J. Antonio Perez M.
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
INFINITY POWER
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Shmuel (Seymour J.) Metz
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
magidin@math.berkeley.edu
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
INFINITY POWER
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Virgil
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
JRStern
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
magidin@math.berkeley.edu
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
magidin@math.berkeley.edu
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
magidin@math.berkeley.edu
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Frederick Williams
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
LudovicoVan
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Richard Tobin
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
LudovicoVan
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
J. Antonio Perez M.
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
J. Antonio Perez M.
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
magidin@math.berkeley.edu
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Frederick Williams
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
JRStern
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
magidin@math.berkeley.edu
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Hercules ofZeus
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
magidin@math.berkeley.edu
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Hercules ofZeus
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Arturo Magidin
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Hercules ofZeus
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Arturo Magidin
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Hercules ofZeus
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
J. Antonio Perez M.
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
JRStern
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Frederick Williams
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
magidin@math.berkeley.edu
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Pubkeybreaker
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
JRStern
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
magidin@math.berkeley.edu
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
JRStern
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
magidin@math.berkeley.edu
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
magidin@math.berkeley.edu
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
J. Antonio Perez M.
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
magidin@math.berkeley.edu
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Shmuel (Seymour J.) Metz
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Virgil
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
MoeBlee
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
11/2/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
11/1/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
11/1/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Hercules ofZeus
11/2/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Richard Tobin
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
MoeBlee
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
MoeBlee
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Richard Tobin
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Richard Tobin
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Richard Tobin
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
LudovicoVan
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
J. Antonio Perez M.
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
LudovicoVan
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
LudovicoVan
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
LudovicoVan
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
LudovicoVan
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
J. Antonio Perez M.
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
LudovicoVan
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Virgil
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
J. Antonio Perez M.
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
LudovicoVan
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
LudovicoVan
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
J. Antonio Perez M.
10/30/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
adamk
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Shmuel (Seymour J.) Metz
11/1/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
LudovicoVan
11/1/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Jesse F. Hughes
11/2/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
11/2/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
LudovicoVan
11/2/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
11/2/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Shmuel (Seymour J.) Metz
11/2/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Virgil
11/2/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
11/2/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
11/3/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
J. Antonio Perez M.
11/3/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Shmuel (Seymour J.) Metz
11/4/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Peter Webb
11/4/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Virgil
11/4/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Shmuel (Seymour J.) Metz
11/1/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Shmuel (Seymour J.) Metz
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Shmuel (Seymour J.) Metz
10/31/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Shmuel (Seymour J.) Metz
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
JRStern
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Shmuel (Seymour J.) Metz
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Graham Cooper
10/28/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
J. Antonio Perez M.
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
David C. Ullrich
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
JRStern
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
LudovicoVan
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Fernando Revilla
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
Shmuel (Seymour J.) Metz
10/29/12
Read Re: Peer-reviewed arguments against Cantor Diagonalization
adamk

Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© Drexel University 1994-2014. All Rights Reserved.
The Math Forum is a research and educational enterprise of the Drexel University School of Education.