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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 12:06 AM

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

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