1.6.1 "Then what? Isn't castigation sometimes necessary?" Why not? But (we do) that with consideration, not with anger; for it doesn't harm but heal with pretence of harming. Just as we burn certain distorted shafts to straighten (them) and we strike (them) not to break but to unfold (them), with wedges hurled, so we straighten the talents, (which are) perverse with vices, with pain of body and mind.
1.6.2 Indeed, in (case of) light illness, a doctor at first doesn't try to change a lot of everyday habit, but to put foods, drinks, and exercises in order, and to confirm health only by changing the disposition of one's life. Next he lets limitation benefits (the patient). If limitation and order are not useful, he cuts off and remove somthing; If it doesn't yet respond indeed, he forbids (the patient) from foods and unload the body by fasting; If lighter (cures) result in vain, he cuts veins and gives his hands (=perform an operation) onto the limbs, if the clinging (badnesses) harm and diffuse the disease; any cure whose effect is healthy doesn't seem harsh.
1.6.3 Thus it is decent for a protector of laws and a leader of a state, as long as possible, to cure their tempers with words, even with softer ones, so that he would persuade (them) (to do) what are to be done, recommend a desire of honourable and just mind, and arouse hatred of vices and pride of virtues; He then would change his oration (=words) into harsh one, with which he would yet warn and reproach; At last he would go down to punishments, but yet light and revocable ones; He would carry out the maximum penalties (only) for maximum crimes so that none would die unless someone's dying be of interest of the dying man himself.
1.6.4 He (=the protector of laws) is not similar to doctors in one point: that (while) they give an easy death (=euthanasia) to those whom they can no longer dispense life to, he drives out from life those condemned with dishonour and public disgrace (=public execution), not because he is pleased with the someone's punishment ―― for such an inhumane savageness is far from the Wise ―― but so that it (=the punishment) would be a lesson to everyone and, because they (=the criminals) haven't wanted to be beneficial when living, the republic would certainly make use of their death. Thus man's nature is not desirous of punishment; and so even anger is not following man's nature because it is desirous of punishment.
1.6.5 I will also adduce Plato's argument ―― for, why is it harmful to make use of others' (arguments) in the part where ours are (as well)? Plato says, "A good man doesn't hurt (others)." Punishment hurts; Thus punishment is not fitting to a good man, nor is anger from this point, because punisment is fitting to anger. If a good man isn't pleased with punishment, he isn't pleased even with the affection, for which punishment is a pleasure; Thus anger is not natural.