But they think it is very important with reference to this subject, that it should be understood that it is the work of nature, that children are beloved by their parents; and that this is the first principle from which we may trace the whole progress of the common society of the human race. And that this may be inferred, in the first place, from the figure and members of the body, which of themselves declare that a due regard for everything connected with generation has been exhibited by nature; nor can these two things possibly be consistent with one another, that nature should desire that offspring should be propagated, and yet take no care that what is propagated should be loved. But even in beasts the power of nature may be discerned; for when we see such labour bestowed upon the bringing forth and bearing of their offspring, we seem to be hearing the voice of nature herself. Wherefore, as it is evident that we are by nature averse to pain; so also it is clear that we are impelled by nature herself to love those whose existence we have caused. And from this it arises that there is such a recommendation by nature of one man to another, that one man ought never to appear unfriendly to another, for the simple reason that he is a man.
For as among the limbs some appear to be created for themselves as it were, as the eyes and ears; others assist the rest of the limbs, as the legs and hands; so there are some monstrous beasts born for themselves alone: but that fish which floats in an open shell and is called the pinna, and that other which swims out of the shell, and, because it is a guard to the other, is called the pinnoteres, and when it has withdrawn within the shell again, is shut up in it, so that itappears that it has given it warning to be on its guard; and also ants, and bees, and storks, do something for the sake of others. Much more is this the case with reference to the union of men. And therefore we are by nature adapted for companionship, for taking counsel together, for forming states. But they think that this world is regulated by the wisdom of the gods, and that it is, as it were, a common city and state of men and gods, and that every individual of us is a part of the world. From which that appears to follow by nature, that we should prefer the general advantage to our own. For as the laws prefer the general safety to that of individuals, so a good and wise man, and one who obeys the laws and who is not ignorant of his duty as a citizen, consults the general advantage rather than that of any particular individual, or even than his own. Nor is a betrayer of his country more to be blamed, than one who deserts the general advantage or the general safety on account of his own private advantage or safety. From which it also follows, that that man deserves to be praised who encounters death voluntarily for the sake of the republic, because it is right that the republic should be dearer to us than ourselves. And since it is said to be a wicked thing, and contrary to human nature, for a man to say that he would not care if, after his own death, a general conflagration of the whole world were to happen, which is often uttered in a Greek verse; so it is certainly true that we ought to consult the interests of those who are to come after us, for the sake of the love which we bear them.