We can think of the base set as consisting of all objects. Then we can promote them to a higher state to create a number chain.
So the number 1, 2, 3, etc. already exist in the base set. Then we put them into the marked or excited state or spin up state or positive energy state. These latter are analogs to quantum field theory and Dirac Hole Theory.
The base set is like the vacuum in quantum field theory. It is a source of creativity and we can create particles, numbers or reality out of it.