There is no truth, then, in such pretexts. It can be urged with more justice that as, when you snarl at a dog, he snarls in return, and when you pet him, he fawns; so it lies in the nature of men to return hostility by hostility, and to be embittered and irritated at any signs of depreciatory treatment or hatred: and, as Cicero says, _there is something so penetrating in the shaft of envy that even men of wisdom and worth find its wound a painful one_; and nowhere in the world, except, perhaps, in a few religious sects, is an insult or a blow taken with equanimity. And yet a natural view of either would in no case demand anything more than a requital proportionate to the offence, and would never go to the length of assigning _death_ as the proper penalty for anyone who accuses another of lying or stupidity or cowardice. The old German theory of _blood for a blow_ is a revolting superstition of the age of chivalry. And in any case the return or requital of an insult is dictated by anger, and not by any such obligation of honor and duty as the advocates of chivalry seek to attach to it. The fact is that, the greater the truth, the greater the slander; and it is clear that the slightest hint of some real delinquency will give much greater offence than a most terrible accusation which is perfectly baseless: so that a man who is quite sure that he has done nothing to deserve a reproach may treat it with contempt, and will be safe in doing so. The theory of honor demands that he shall show a susceptibility which he does not possess, and take bloody vengeance for insults which he cannot feel. A man must himself have but a poor opinion of his own worth who hastens to prevent the utterance of an unfavorable opinion by giving his enemy a black eye.