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Topic: How do you prove that 2+2=4? Is it enough to consider 2 objects,
then 2 more then put them together and count them and get 4, or do you have
to resort to fancy-schmancy methods?

Replies: 8   Last Post: Nov 18, 2012 7:45 PM

 Messages: [ Previous | Next ]
 Charlie-Boo Posts: 1,635 Registered: 2/27/06
Re: How do you prove that 2+2=4? Is it enough to consider 2 objects,
then 2 more then put them together and count them and get 4, or do you have
to resort to fancy-schmancy methods?

Posted: Nov 16, 2012 12:46 AM

On Nov 16, 12:33 am, William Hale <bill...@yahoo.com> wrote:
> In article
>
>  Charlie-Boo <shymath...@gmail.com> wrote:

> > On Nov 15, 11:22 pm, donstockba...@hotmail.com wrote:
>
> > Principia Mathematica BS says it takes 100 pages.  I don't know
> > anybody who has tried to explain what is going on there (everyone just
> > sits in awe at the number of pages), but Peano Arithmetic proves it in
> > a few steps where 2 is 0'' and 4 is 0'''', based on the axioms x+0=x
> > and x+y' = (x+y)' where x' is x+1 ("successor of x").

>
> > C-B
>
> You can view "Prinicpia Mathematica" at the link:
>
> incipiaMathematicaVolumeI#page/n95/mode/2up
>
> More is being done than just proving that "2+2=4". For example, logical
> propositions like "q implies (p implies q)" are being proved.

People always say "It takes 100 pages to prove 1+1=2!" as if it's
cool, contrary to Occam's Razor. So how many pages are needed for the
ultimate derivation of 1+1=2 (or 2+2=4 whatever)?

C-B

Date Subject Author
11/15/12 donstockbauer@hotmail.com
11/15/12 William Elliot
11/16/12 Charlie-Boo
11/16/12 William Hale
11/16/12 Charlie-Boo
11/16/12 William Hale
11/17/12 Charlie-Boo
11/18/12 harold james
11/18/12 William Hale