Freud's postulate of the Unconscious mind as a structure of forgotten unrecoverable memories is a precursor of the rebirth theory. It prepares the way for scientific acceptance of the latter and should inevitably lead to it. In turn, it throws light on the doctrine of karma. For the ego which revives out of apparent nothingness is the conscious mind which reappears out of the unconscious. When the production of these idea-energies (that is, tendencies, samskaras) is brought to rest, then they can never again objectify into a physical environment, a fresh rebirth, and thus man becomes karma-free and enters Nirvana. As long as he believes that he is the body he must reincarnate in the body.
-- Notebooks Category 9: From Birth to Rebirth > Chapter 2: Rebirth and Reincarnation > # 98
-- Perspectives > Chapter 9: From Birth to Rebirth > # 27