Some precious achievements have survived all the vicissitudes of rising and falling states: the making of fire and light, of the wheel and other basic tools; language, writing, art, and song; agriculture, the family, and parental care; social organization, morality, and charity; and the use of teaching to transmit the lore of the family and the race. These are the elements of civilization, and they have been tenaciously maintained through the perilous passage from one civilization to the next. They are the connective tissue of human history.
