Energy conveys to us the idea of motion and activity. Inside a living organism we see a source of power, which by some manner is released in terms of movement.... Life is energy... it is the creator or initiator of movement change, development. We are different from moment to moment because the life principle is at work with us.... The spirit of humanity, like the forces of nature, and like the physical life, is at bottom energy.... Spiritual life, therefore, is just as much a development out of what has gone before in the evolutionary process as physical life is; which means that the origin of spiritual life is from within.