Reincarnation and the Law of Karma - William Atkinson - Bog

"the doctrine of Reincarnation played a very important part in their philosophy. The prevailing idea was that the worthy souls pass on to a state of bliss, without rebirth, while the less worthy pass the waters of the river of Lethe, quaffing of its waters of forgetfulness, and thus having the recollection of their earth-life, and of the period of punishment that they had undergone by reason of the same, obliterated and cleansed from their memories, when they pass on to re-birth."