As it dies it turns black, putrefies, and is filled with poison. The alchemist then enters the picture and subjects the poison-laden carcass to the fire of the alchemical process… the poison is changed to a paradoxical medicine that can kill or save, the elixir.
Edinger demonstrates that in alchemical psychotherapy, poison generated by the mortification of the prima materia is the very substance that, when processed, becomes the paradoxical elixir — establishing poison as structurally necessary to transformation.
, Anatomy of the Psyche: Alchemical Symbolism in Psychotherapy, 1985thesis