How to Create a Set of Natural Numbers

There are two rules. First rule is, you get zero. Second rule is, any number you could create, you cn create a successor. And so that's the set of natural numbers - considered a mathematically precise definition. But it took mathematicians a while to accept this because there were no negative numbers or complex imaginary numbers until around 18 hundred years ago. The era of not allowing certain constructs in mathematics has now been 'killed', says Hilbert.