Jung linked the collective unconscious to 'what Freud called "archaic remnants" – mental forms whose presence cannot be explained by anything in the individual's own life and which seem to be aboriginal, innate, and inherited shapes of the human mind'. He credited Freud for developing his "primal horde" theory in "Totem and Taboo" and continued further with the idea of an archaic ancestor maintaining its influence in the minds of present-day humans. Every human being, he wrote, "however high his conscious development, is still an archaic man at the deeper levels of his psyche."