Wallace thought that natural selection could not account for mathematical, artistic, or musical genius, as well as metaphysical musings, wit and humour. He eventually said that something in "the unseen universe of Spirit" had interceded at least three times in history. The first was the creation of life from inorganic matter. The second was the introduction of consciousness in the higher animals. And the third was the generation of the higher mental faculties in mankind. He also believed that the purpose of the universe was the development of the human spirit. 