Mathematics is both a part of the way we think, that is, an abstraction, a construct of the mind, and a powerful tool in understanding how the world really works. The reason for this is that the way we think corresponds in a deep way to how the world works. People often create a false dichotomy between mathematics having some sort of independent existence, and mathematics as a product of the human psyche, but it's not one, or the other. It's both. Mathematics is both a labyrinth of the mind we are in the process of inventing and discovering, and a window into the mysteries of the universe itself.