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Single Idea 15717

[filed under theme 4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX ]

Full Idea

The problem with the Axiom of Choice is that it allows an initiate (by an ingenious train of reasoning) to cut a golf ball into a finite number of pieces and put them together again to make a globe as big as the sun.

Gist of Idea

Using Choice, you can cut up a small ball and make an enormous one from the pieces

Source

R Kaplan / E Kaplan (The Art of the Infinite [2003], 9)

Book Ref

Kaplan,R and Kaplan,E: 'The Art of the Infinite' [Penguin 2004], p.256


A Reaction

I'm not sure how this works (and I think it was proposed by the young Tarski), but it sounds like a real problem to me, for all the modern assumptions that Choice is fine.


The 6 ideas from 'The Art of the Infinite'

1 and 0, then add for naturals, subtract for negatives, divide for rationals, take roots for irrationals [Kaplan/Kaplan]
The rationals are everywhere - the irrationals are everywhere else [Kaplan/Kaplan]
The first million numbers confirm that no number is greater than a million [Kaplan/Kaplan]
'Commutative' laws say order makes no difference; 'associative' laws say groupings make no difference [Kaplan/Kaplan]
'Distributive' laws say if you add then multiply, or multiply then add, you get the same result [Kaplan/Kaplan]
Using Choice, you can cut up a small ball and make an enormous one from the pieces [Kaplan/Kaplan]