Few images are as enigmatic as the Ouroboros, the serpent consuming its own tail. Its roots go back to ancient Egypt where it is first seen in the Pyramid of Unas as "a serpent entwined by a serpent" connoting a union of opposites. The Ouroboros can also represent cyclicality - the end is the beginning. It represents the idea of primordial unity or, in alchemical terms, a symbol of the eternal unity achieved by the opus of devouring oneself (ego) and overcoming or assimilating our darker opposite, i.e. Nietzsche's as well as Jung's 'shadow.' As Jung suggested, "The Ouroboros is a dynamic symbol for the integration and assimilation of the opposite, i.e., of the shadow. . ."