even before the final dissolution of the human body of the moment of death there is incessant transmigration of the bodily atoms… That which is common to the human and to the sub-human worlds alike, namely, matter in its varied aspects as solids, liquids, and gases, eternally transmigrates.
Evans-Wentz argues that transmigration operates at both the material-atomic level and the consciousness level, using the esoteric Bardo doctrine to reframe the concept as a universal, continuous process rather than a discrete post-mortem event.
, The Tibetan Book of the Dead (Evans-Wentz Edition), 1927thesis