Arithmetic is numbers you squeeze from your head to your hand to your pencil to your paper till you get the answer. – Carl Sandburg, "Arithmetic"

As far as the laws of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality. – Albert Einstein, Sidelights on Relativity

But mathematics is the sister, as well as the servant, of the arts and is touched with the same madness and genius. – Harold Marston Morse

Why do we believe that in all matters the odd numbers are more powerful? – Pliny the Elder, Natural History