And Pythagoras, son of Mnesarchus, who expounded the doctrines of his own philosophy, mystically by means of symbols, as those who have written his life show, himself seems to have entertained thoughts about the unity of God not unworthy of his foreign residence in Egypt. For when he says that unity is the first principle of all things, and that it is the cause of all good, he teaches by an allegory that God is one, and alone. ^[2545] And that this is so, is evident from his saying that unity and one differ widely from one another. For he says that unity belongs to the class of things perceived by the mind, but that one belongs to numbers. And if you desire to see a clearer proof of the opinion of Pythagoras concerning one God, hear his own opinion, for he spoke as follows: "God is one; and He Himself does not, as some suppose, exist outside the world, but in it, He being wholly present in the whole circle, and beholding all generations; being the regulating ingredient of all the ages, and the administrator of His own powers and works, the first principle of all things, the light of heaven, and Father of all, the intelligence and animating soul of the universe, the movement of all orbits." Thus, then, Pythagoras.