Those in whom anger or desire or any other passion, or again any insidious vice holds sway, are entirely enslaved, while all whose life is regulated by law are free. And right reason is an infallible law engraved not by this mortal or that and, therefore, perishable as he, nor on parchment slabs, and, therefore, soulless as they, but by immortal nature on the immortal mind, never to perish.