From justice flows also equity, which makes us declare the needs of all human beings to be our own, and to believe that we are born not for ourselves alone, but also for the human race; and to avoid whatever can harm any human being, as though it harmed ourselves: because we who are human ought to think nothing human alien to us. Inasmuch as it is the part of beasts to live for oneself and not to contribute one's own advantages to the common good. From these we differ not only by the prerogative of mind, but also by the preserved equality of right, if—considering ourselves in the gains or losses of all—we live for the utilities of all the partners of our nature, just as for our own advantages.
Then, if to persecute, tear, or destroy one another is proper to wild beasts, who would doubt that it befits human excellence that they should help, instruct, and edify one another, and care for the common utility as for their own? Whence it is given to understand that those who, born as human beings, persist in oppressing and deceiving human beings, degenerate into beastly ways—by a change not of nature, but of life.