Let us consider a further point. The matters which are now in question are generally called customs rather than laws; and we have already made the reflection that, though they are not, properly speaking, laws, yet neither can they be neglected. For they fill up the interstices of law, and are the props and ligatures on which the strength of the whole building depends. Laws without customs never last; and we must not wonder if habit and custom sometimes lengthen out our laws. 'Very true.' Up to their third year, then, the life of children may be regulated by customs such as we have described. From three to six their minds have to be amused; but they must not be allowed to become self-willed and spoilt. If punishment is necessary, the same rule will hold as in the case of slaves; they must neither be punished in hot blood nor ruined by indulgence. The children of that age will have their own modes of amusing themselves; they should be brought for their play to the village temples, and placed under the care of nurses, who will be responsible to twelve matrons annually chosen by the women who have authority over marriage. These shall be appointed, one out of each tribe, and their duty shall be to keep order at the meetings: slaves who break the rules laid down by them, they shall punish by the help of some of the public slaves; but citizens who dispute their authority shall be brought before the magistrates. After six years of age there shall be a separation of the sexes; the boys will go to learn riding and the use of arms, and the girls may, if they please, also learn. Here I note a practical error in early training. Mothers and nurses foolishly believe that the left hand is by nature different from the right, whereas the left leg and foot are acknowledged to be the same as the right. But the truth is that nature made all things to balance, and the power of using the left hand, which is of little importance in the case of the plectrum of the lyre, may make a great difference in the art of the warrior, who should be a skilled gymnast and able to fight and balance himself in any position. If a man were a Briareus, he should use all his hundred hands at once; at any rate, let everybody employ the two which they have. To these matters the magistrates, male and female, should attend; the women superintending the nursing and amusement of the children, and the men superintending their education, that all of them, boys and girls alike, may be sound, wind and limb, and not spoil the gifts of nature by bad habits.