Every virtue is perfected, as was shown by us in the beginning, from reason, deliberate choice, and power. Each of these, however, is not by itself a part of virtue, but the cause of it. Such therefore, as have the intellective and gnostic part of virtue,[67] are denominated skilful and intelligent; but such as have the ethical and pre-elective part of it, are denominated useful and equitable.[68] Since however, man is naturally adapted to act unjustly from exciting causes; and these are three, the love of pleasure in corporeal enjoyments; avarice, in the accumulation of wealth; and ambition, in surpassing those that are equal and similar to him;—this being the case, it is necessary to know, that it is possible to oppose to these such things as procure fear, shame, and desire in men; viz. fear through the laws, shame through the Gods, and desire through the energies of reason. Hence, it is necessary that youth should be taught from the first to honor the Gods and the laws. For from these, it will be manifest, that every human work, and every kind of human life, by the participation of sanctity and piety, will sail prosperously [over the sea of generation].