The prime principle in man's constitution is social. The next in order is not to yield to the persuasions of the body, when they are not conformable to the rational principle, which must govern. The third is freedom from error and from deception. "Let then the ruling principle holding fast to these things go straight on, and it has what is its own" (vii. 55). The emperor selects justice as the virtue which is the basis of all the rest (x. 11), and this had been said long before his time. It is true that all people have some notion of what is meant by justice as a disposition of the mind, and some notion about acting in conformity to this disposition; but experience shows that men's notions about justice are as confused as their actions are inconsistent with the true notion of justice. The emperor's notion of justice is clear enough, but not practical enough for all mankind. "Let there be freedom from perturbations with respect to the things which come from the external cause; and let there be justice in the things done by virtue of the internal cause, that is, let there be movement and action terminating in this, in social acts, for this is according to thy nature" (ix. 31). In another place (ix. 1) he says that "he who acts unjustly acts impiously," which follows of course from all that he says in various places. He insists on the practice of truth as a virtue and as a means to virtue, which no doubt it is: for lying even in indifferent things weakens the understanding; and lying maliciously is as great a moral offense as a man can be guilty of, viewed both as showing an habitual disposition, and viewed with respect to consequences. He couples the notion of justice with action. A man must not pride himself on having some fine notion of justice in his head, but he must exhibit his justice in act, like St. James' notion of faith. But this is enough.