The parents ought to be in the prime of life, which for a man may be reckoned at thirty years—from twenty-five, when he has ‘passed the point at which the speed of life is greatest,’ to fifty-five; and at twenty years for a woman—from twenty to forty. Any one above or below those ages who partakes in the hymeneals shall be guilty of impiety; also every one who forms a marriage connexion at other times without the consent of the rulers. This latter regulation applies to those who are within the specified ages, after which they may range at will, provided they avoid the prohibited degrees of parents and children, or of brothers and sisters, which last, however, are not absolutely prohibited, if a dispensation be procured. ‘But how shall we know the degrees of affinity, when all things are common?’ The answer is, that brothers and sisters are all such as are born seven or nine months after the espousals, and their parents those who are then espoused, and every one will have many children and every child many parents. Socrates proceeds: I have now to prove that this scheme is advantageous and also consistent with our entire polity. The greatest good of a State is unity; the greatest evil, discord and distraction. And there will be unity where there are no private pleasures or pains or interests—where if one member suffers all the members suffer, if one citizen is touched all are quickly sensitive; and the least hurt to the little finger of the State runs through the whole body and vibrates to the soul. For the true State, like an individual, is injured as a whole when any part is affected. Every State has subjects and rulers, who in a democracy are called rulers, and in other States masters: but in our State they are called saviours and allies; and the subjects who in other States are termed slaves, are by us termed nurturers and paymasters, and those who are termed comrades and colleagues in other places, are by us called fathers and brothers. And whereas in other States members of the same government regard one of their colleagues as a friend and another as an enemy, in our State no man is a stranger to another; for every citizen is connected with every other by ties of blood, and these names and this way of speaking will have a corresponding reality—brother, father, sister, mother, repeated from infancy in the ears of children, will not be mere words. Then again the citizens will have all things in common, in having common property they will have common pleasures and pains.