Whereas Book I is intended to reject the doctrine of innate ideas proposed by Descartes and the rationalists, Book II explains that every idea is derived from experience either by sensation – direct sensory information – or reflection – "the perception of the operations of our own mind within us, as it is employed about the ideas it has got". Furthermore, Book II is also a systematic argument for the existence of an intelligent being: "Thus, from the consideration of ourselves, and what we infallibly find in our own constitutions, our reason leads us to the knowledge of this certain and evident truth, that there is an eternal, most powerful, and most knowing being; which whether any one will please to call God, it matters not!"