1Of the three that remain, the most wide-ranging is the principle by which the society of men among themselves and, as it were, the community of life is held together; 1it has two parts: justice, in which the splendour of virtue is greatest and from which men are called good, and, joined to it, beneficence, which may also be called kindness or generosity. 1But the first function of justice is that no one should harm anyone unless provoked by wrong, and next that one should use common things as common and private things as one's own. 21Now nothing is private by nature, but either by ancient occupation, as with those who once came into empty lands, or by victory, as with those who took possession in war, or by law, agreement, contract or lot; 21whence it comes about that the land of Arpinum is said to belong to the Arpinates, that of Tusculum to the Tusculans; 21and similar is the allotment of private possessions.
21Hence, since each man's own comes from what by nature had been common, let each hold whatever has fallen to him; 21if anyone seeks any of this for himself, he will violate the law of human society. 22But since, as Plato has finely written, we are not born for ourselves alone, but our country claims a share of our existence and our friends a share, and since, as the Stoics hold, all that the earth produces is created for the use of men, while men were born for the sake of men, so that they might be able to benefit one another, in this we ought to follow nature as our guide, to bring common advantages into the common stock by exchanging services, by giving and receiving, and by skills, by labour and by resources to bind fast the fellowship of men with men.
23Now the foundation of justice is good faith, that is, constancy and truthfulness in what is said and agreed. 23Hence, although this will perhaps seem rather strained to some, let us nevertheless dare to imitate the Stoics, who diligently inquire where words come from, and let us believe that good faith, fides, is so called because what has been said is done, fiat. 23But there are two kinds of injustice: one of those who inflict wrong, the other of those who, though they can, do not ward off wrong from those on whom it is inflicted. 23For he who unjustly attacks someone, spurred on either by anger or by some other passion, seems as it were to lay hands on a comrade; 23but he who does not defend or resist the wrong, if he can, is as much at fault as if he were deserting his parents or friends or country.
24And those wrongs which are inflicted deliberately for the purpose of harm often arise from fear, when he who plans to harm another fears that unless he does so he himself will suffer some harm. 24For the most part, however, men set about doing wrong in order to obtain what they have coveted; 24and in this vice greed is the most widespread.