There is a closer tie than is commonly supposed between the improvement of the soul and the amelioration of what belongs to the body. Man may leave these two things apart and consider each of them alternately, but he cannot sever them entirely without at last losing sight of both. The beasts have the same senses as ourselves, and very nearly the same appetites. We have no sensual passions which are not common to our race and theirs and which are not to be found, at least in the germ, in a dog as well as in a man. Whence is it, then that the animals can provide only for their first and lowest wants, whereas we can infinitely vary and endlessly increase our enjoyments?

Whatever elevates, enlarges, and expands the soul renders it more capable of succeeding in those very undertakings which do not concern it. Whatever, on the other hand, enervates or lowers it weakens it for all purposes, the chief as well as the least, and threatens to render it almost equally impotent for both. Hence the soul must remain great and strong, though it were only to devote its strength and greatness from time to time to the service of the body. If men were ever to content themselves with material objects, it is probable that they would lose by degrees the art of producing them; and they would enjoy them in the end, like the brutes, without discernment and without improvement.