Combining Texts

Ideas for 'Two Notions of Being: Entity and Essence', 'System of Logic' and 'The Art of the Infinite'

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2 ideas

4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
Using Choice, you can cut up a small ball and make an enormous one from the pieces [Kaplan/Kaplan]
     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.
     From: R Kaplan / E Kaplan (The Art of the Infinite [2003], 9)
     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.
4. Formal Logic / F. Set Theory ST / 7. Natural Sets
What physical facts could underlie 0 or 1, or very large numbers? [Frege on Mill]
     Full Idea: What in the world can be the observed fact, or the physical fact, which is asserted in the definition of the number 777864? ...What a pity that Mill did not also illustrate the physical facts underlying the numbers 0 and 1!
     From: comment on John Stuart Mill (System of Logic [1843]) by Gottlob Frege - Grundlagen der Arithmetik (Foundations) §7
     A reaction: I still think patterns could be an empirical foundation for arithmetic, though you still have to grasp the abstract concept of the pattern. An innate capacity to spot resemblance gets you a long way.