Number does exist in nature. It is part and parcel of existence.
No it doesn't. Numbers are mental abstractions. Perception of 'red' is perception of some property in a thing, but assigning a number to a set of objects is a purely mental operation. For example, if I have two golden finches, can you point to any property in either finch that contains its 'twoness'?
And it is because numbers are purely mental phenomena that we can have absolute certainty about the statements we make about them. If they were real properties of things, we would have the same difficulty we have with other properties of things - i.e. any statement we made about them could only have high probability associated with it, never absolute certainty. (This, at bottom, is the difference between science and mathematics).
'I can't even fit all my wife's clothes into a suitcase for travelling. So you want me to believe we're going to put all of the planets and stars and everything into a sandwich bag?' - q3psycho on the Big Bang
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