He thinks not of others but of himself, and prefers that others should do the same. He makes no claim upon them, and acknowledges no debt to them. He is alone in the midst of human society, he depends on himself alone, for he is all that a boy can be at his age. He has no errors, or at least only such as are inevitable; he has no vices, or only those from which no man can escape. His body is healthy, his limbs are supple, his mind is accurate and unprejudiced, his heart is free and untroubled by passion. Pride, the earliest and the most natural of passions, has scarcely shown itself. Without disturbing the peace of others, he has passed his life contented, happy, and free, so far as nature allows. Do you think that the earlier years of a child, who has reached his fifteenth year in this condition, have been wasted? BOOK IV How swiftly life passes here below! The first quarter of it is gone before we know how to use it; the last quarter finds us incapable of enjoying life. At first we do not know how to live; and when we know how to live it is too late. In the interval between these two useless extremes we waste three-fourths of our time sleeping, working, sorrowing, enduring restraint and every kind of suffering. Life is short, not so much because of the short time it lasts, but because we are allowed scarcely any time to enjoy it. In vain is there a long interval between the hour of death and that of birth; life is still too short, if this interval is not well spent. We are born, so to speak, twice over; born into existence, and born into life; born a human being, and born a man. Those who regard woman as an imperfect man are no doubt mistaken, but they have external resemblance on their side. Up to the age of puberty children of both sexes have little to distinguish them to the eye, the same face and form, the same complexion and voice, everything is the same; girls are children and boys are children; one name is enough for creatures so closely resembling one another. Males whose development is arrested preserve this resemblance all their lives; they are always big children; and women who never lose this resemblance seem in many respects never to be more than children. But, speaking generally, man is not meant to remain a child. He leaves childhood behind him at the time ordained by nature; and this critical moment, short enough in itself, has far-reaching consequences. As the roaring of the waves precedes the tempest, so the murmur of rising passions announces this tumultuous change; a suppressed excitement warns us of the approaching danger. A change of temper, frequent outbreaks of anger, a perpetual stirring of the mind, make the child almost ungovernable. He becomes deaf to the voice he used to obey; he is a lion in a fever; he distrusts his keeper and refuses to be controlled.