text: Indeed, to sum up, that alone is perfect which is perfect according to nature as a whole, and nature as a whole is possessed of reason. Other things can be perfect according to their kind. That which cannot contain the happy life cannot contain that which produces the happy life; and the happy life is produced by Goods alone. In dumb animals there is not a trace of the happy life, nor of the means whereby the happy life is produced; in dumb animals the Good does not exist. The dumb animal comprehends the present world about him through his senses alone. He remembers the past only by meeting with something which reminds his senses; a horse, for example, remembers the right road only when he is placed at the starting-point. In his stall, however, he has no memory of the road, no matter how often he may have stepped along it. The third state – the future – does not come within the ken of dumb beasts.