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




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 fancyschmancy methods?
Posted:
Nov 16, 2012 12:46 AM


On Nov 16, 12:33 am, William Hale <bill...@yahoo.com> wrote: > In article > <17eeb6262a354177ad6892cf18be5...@c16g2000yqe.googlegroups.com>, > > CharlieBoo <shymath...@gmail.com> wrote: > > On Nov 15, 11:22 pm, donstockba...@hotmail.com wrote: > > > Just askin. > > > 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"). > > > CB > > You can view "Prinicpia Mathematica" at the link: > > http://archive.org/stream/PrincipiaMathematicaVolumeI/WhiteheadRussel... > 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)?
CB



