From: Dan Christensen on
On Jun 17, 5:26 pm, George Greene <gree...(a)email.unc.edu> wrote:
> On Jun 17, 10:42 am, Dan Christensen <Dan_Christen...(a)sympatico.ca>
> wrote:
>
> > On Jun 17, 7:00 am, "|-|ercules" <radgray...(a)yahoo.com> wrote:
>
> > > CANTOR'S POWER PROOF!
> > > Superinfinity is based on the circular reasoning
> > > "no box contains the box numbers that don't contain their own box number".
>
> > I don't know about "boxes" and "box numbers," but it is relatively
> > easy to formally prove the power set of any set s is larger than s:
>
> > Suppose p is the power set of s. Suppose further that f is a
> > surjective function mapping s onto p. Select a subset k containing
> > those and only those elements of s that are not elements of their
> > images under f. (Do you see a problem with that?)
>
> Of course he does.  First of all, you said "those and only those", so
> this
> subset is UNIQUE -- it is THE subset, NOT *a* subset, of those
> elements.

True.

> Second of all, you are talking about elements of s under THEIR OWN
> images,
> so he's going to claim THAT'S SELF-referential!  It ISN'T, and even if
> it WERE
> it would NOT be a PROBLEM, BUT THAT'S THE PROBLEM HE CLAIMS TO SEE!
>

Examples:

Suppose f(1)={1, 2, 3} and f(2)={4, 5, 6}

Then 1 e f(1) and ~ 2 e f(2) and ~ 1 e k and 2 e k.

No self-reference. Not that I see anything inherently wrong with self-
reference. In my opinion, banning it just makes for a more complicated
system of axioms. There are simpler ways of dealing with so-called
paradoxes of self-reference.

> Seriously, you have been around here long enough to know better than
> this.
> This has been going on for close to a decade now and you HAVE been
> here
> for most of it!
>

Thanks for noticing!


> >  k is an element of p, so there must be a pre-image of k under f, say k'. Applying the
> > definition of k, you can then obtain the contradiction k' e k and ~k e k.
>
> > I have generated a formal proof using my DC Proof software (download
> > it free atwww.dcproof.com):
>
> This will be a proof FROM SOME AXIOMS.

The only set theoretic axiom used in this proof is the subset axiom.
The rest is just FOL.


> Herc WILL NOT UNDERSTAND your axioms, let alone think they mean
> something real about sets.  He will also not understand the point that
> THE AXIOM OF INFINITY IS NOT USED in this proof and that therefore,
> infinity simply has nothing to do with this.  

He may be interested to know that, in my set theory, there is no axiom
of infinity. I do not even have a axiom for the empty set. I haven't
found it to be necessary. If I want to do number theory, I start with
an initial premise giving the equivalent of Peano's Axioms. They are
entirely separate from my set theory. (I made these innovations
primarily for pedagogical reasons. I think they really simplify
matters for students first learning how to write formal proofs.)


He will keep trying to
> say that
> the fact that this proof (allegedly) implies the existence of higher
> infinities
> proves that there must be something OBVIOUSLY wrong with it.

I invite him to examine each step of my proof and point out where I
might have gone wrong. It might help me improve my system.


> THAT is what you are dealing with (or not dealing with, since you keep
> trying to explain the proof, which is completely off-topic here, since
> the burden
> of proof is actually ON HERC to identify SOME ERROR IN the proof, and
> he
> thinks he can refuse to shoulder it because he can cry "self-
> reference!" and "superinfinity!"

I always welcome a challenge. ;^)

Dan
From: Dan Christensen on
Did you have chance to look at my proof, Hercules?

Dan

On Jun 18, 1:57 am, Dan Christensen <Dan_Christen...(a)sympatico.ca>
wrote:
> On Jun 17, 5:26 pm, George Greene <gree...(a)email.unc.edu> wrote:
>
>
>
>
>
> > On Jun 17, 10:42 am, Dan Christensen <Dan_Christen...(a)sympatico.ca>
> > wrote:
>
> > > On Jun 17, 7:00 am, "|-|ercules" <radgray...(a)yahoo.com> wrote:
>
> > > > CANTOR'S POWER PROOF!
> > > > Superinfinity is based on the circular reasoning
> > > > "no box contains the box numbers that don't contain their own box number".
>
> > > I don't know about "boxes" and "box numbers," but it is relatively
> > > easy to formally prove the power set of any set s is larger than s:
>
> > > Suppose p is the power set of s. Suppose further that f is a
> > > surjective function mapping s onto p. Select a subset k containing
> > > those and only those elements of s that are not elements of their
> > > images under f. (Do you see a problem with that?)
>
> > Of course he does.  First of all, you said "those and only those", so
> > this
> > subset is UNIQUE -- it is THE subset, NOT *a* subset, of those
> > elements.
>
> True.
>
> > Second of all, you are talking about elements of s under THEIR OWN
> > images,
> > so he's going to claim THAT'S SELF-referential!  It ISN'T, and even if
> > it WERE
> > it would NOT be a PROBLEM, BUT THAT'S THE PROBLEM HE CLAIMS TO SEE!
>
> Examples:
>
> Suppose f(1)={1, 2, 3}  and  f(2)={4, 5, 6}
>
> Then 1 e f(1)  and  ~ 2 e f(2)  and  ~ 1 e k  and 2 e k.
>
> No self-reference. Not that I see anything inherently wrong with self-
> reference. In my opinion, banning it just makes for a more complicated
> system of axioms. There are simpler ways of dealing with so-called
> paradoxes of self-reference.
>
> > Seriously, you have been around here long enough to know better than
> > this.
> > This has been going on for close to a decade now and you HAVE been
> > here
> > for most of it!
>
> Thanks for noticing!
>
> > >  k is an element of p, so there must be a pre-image of k under f, say k'. Applying the
> > > definition of k, you can then obtain the contradiction k' e k and ~k e k.
>
> > > I have generated a formal proof using my DC Proof software (download
> > > it free atwww.dcproof.com):
>
> > This will be a proof FROM SOME AXIOMS.
>
> The only set theoretic axiom used in this proof is the subset axiom.
> The rest is just FOL.
>
> > Herc WILL NOT UNDERSTAND your axioms, let alone think they mean
> > something real about sets.  He will also not understand the point that
> > THE AXIOM OF INFINITY IS NOT USED in this proof and that therefore,
> > infinity simply has nothing to do with this.  
>
> He may be interested to know that, in my set theory, there is no axiom
> of infinity. I do not even have a axiom for the empty set. I haven't
> found it to be necessary. If I want to do number theory, I start with
> an initial premise giving the equivalent of Peano's Axioms. They are
> entirely separate from my set theory. (I made these innovations
> primarily for pedagogical reasons. I think they really simplify
> matters for students first learning how to write formal proofs.)
>
> He will keep trying to
>
> > say that
> > the fact that this proof (allegedly) implies the existence of higher
> > infinities
> > proves that there must be something OBVIOUSLY wrong with it.
>
> I invite him to examine each step of my proof and point out where I
> might have gone wrong. It might help me improve my system.
>
> > THAT is what you are dealing with (or not dealing with, since you keep
> > trying to explain the proof, which is completely off-topic here, since
> > the burden
> > of proof is actually ON HERC to identify SOME ERROR IN the proof, and
> > he
> > thinks he can refuse to shoulder it because he can cry "self-
> > reference!" and "superinfinity!"
>
> I always welcome a challenge.   ;^)
>
> Dan