The Forbidden Fountain of Oz food, which occurs most famously in the "forbidden fruit" of the Tree of Knowledge of Good and Evil in the Book of Genesis, but in other contexts too. The idea of water that purges the drinker's memory is also ancient. In Greek mythology it occurs as the river Lethe: the souls of the dead lose their memories of their earthly lives by drinking its water. The same idea can also be found in Eastern and other literatures, as in the "Well of the Waters of Forgetfulness" and other guises. "The 'Drink of Forgetfulness' is found in Greek, Hindu, Norse, and
Chinese mythology on earth, and that adequate records are kept about the process. One example being Yánluó the wáng ("King Yanluo"). Various functions are said to be performed by minor officials and their minions, such as Ox-Head and Horse-Face, humanoid devils with animal features. The functions performed in Diyu tend to focus on punishment by torture according to the crimes committed during life, weighed against any merits earned through good deeds through a process of judgment. In some versions of mythology or Chinese folk religion, the souls are re-incarnated after being given the Drink of Forgetfulness by Meng Po. Much mythology involves