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- Are all infinities equal? 5 answers
I asked a math professor once about infinity and his answer puzzled me. I asked if i had two sets of numbers:
A = all the whole numbers in infinity B = all the whole and half numbers (1, 1.5, 2, 2.5 etc...)
Is B twice as large as A? He chuckled and said no, and then explained something about ordinal and cardinal numbers, that left me confused and still not understanding why my logic that it would be twice as large (and not the same size as he argued) did not hold up. Any good way to explain it to a non-mathematician?