I've always wondered about this very fundamental question. Who SAID, their names were Adam and Eve? If these were the first and only humans in the world, and they bore sons Cain, Abel, and other children, who did their children sleep with to create the grandchildren of Adam and Eve? Does this mean incest was going on here? For literal thinking bible believers, that would have to be the case. The more questions I have, the more I lean toward evolution.