[201] These men affirm that such pieces of prosperity as are granted by fortune, are the body-guards of the body, namely strength and good health, and that the integrity and sound condition of the organs of the external senses, and all things of that kind, are the guards of that princess, the soul; for since the nature of good is divided according to three divisions, the third and outermost is the champion and defender of the second and yielding one, and the second in its turn is a great bulwark and protection to the first;