De anima
Ratramnus wrote two treatises on the soul, upholding traditional Augustinian psychology. The first, "On the Soul", was written against someone named Macarius Scotus, and the second, "The Book on the Soul", addressed to bishop Odo I of Beauvais, challenged an idea raised by an anonymous monk of Fly Abbey – that all human beings participate in a universal soul. In "The Book on the Soul", Ratramnus argued that a soul cannot be universal, only individual.