He next proceeds further to object against himself what is said on behalf of man, viz., that the irrational animals were created on his account, saying: “If one were to call us the lords of the animal creation because we hunt the other animals and live upon their flesh, we would say, Why were not we rather created on their account, since they hunt and devour us? Nay, we require nets and weapons, and the assistance of many persons, along with dogs, when engaged in the chase; while they are immediately and spontaneously provided by nature with weapons which easily bring us under their power.”
And here we may observe, that the gift of understanding has been bestowed upon us as a mighty aid, far superior to any weapon which wild beasts may seem to possess. We, indeed, who are far weaker in bodily strength than the beasts, and shorter in stature than some of them, yet by means of our understanding obtain the mastery, and capture the huge elephants. We subdue by our gentle treatment those animals whose nature it is to be tamed, while with those whose nature is different, or which do not appear likely to be of use to us when tamed, we take such precautionary measures, that when we desire it, we keep such wild beasts shut up; and when we need the flesh of their bodies for food, we slaughter them, as we do those beasts which are not of a savage nature.
The Creator, then, has constituted all things the servants of the rational being and of his natural understanding. For some purposes we require dogs, say as guardians of our sheep-folds, or of our cattle-yards, or goat-pastures, or of our dwellings; and for other purposes we need oxen, as for agriculture; and for others, again, we make use of those which bear the yoke, or beasts of burden. And so it may be said that the race of lions, and bears, and leopards, and wild boars, and such like, has been given to us in order to call into exercise the elements of the manly character that exists within us.
Source: Against Celsus (New Advent)