Note 22 — Chapter II
Reading edition
Mr. Darwin refers to Mr. Herbert Spencer's theory of "the necessary acquirement of each mental power and capacity by gradation"; and indeed it is apparent that this class of philosophers have constructed a theory which denies the creation of the human mind as a spiritual essence, independent of matter, although some of them may adhere to the idea that it was God who caused matter to evolve out of its own action the substance or existence that we call mind.