The perfectly natural performance of function constitutes health; and the perfectly natural performance of function results from the natural action of the Principle of Life. There is a Principle of Life in the universe; it is the One Living Substance from which all things are made. This Living Substance permeates, penetrates, and fills the interspaces of the universe; it is in and through all things, like a ver y refined and diffusible ether. All life comes from it; its life is all the life there is.

Man is a form of this Living Substance, and has within him a Principle of Health. (The word Principle is used as meaning source.) The Principle of Health in man, when in full constructive activity, causes all the voluntar y functions of his life to be perfectly performed.