  Zabarella’s position here can be interpreted as an attempt to raise the status of an independent natural philosophy by emphasizing the nobility of the science of the soul. In fact, it seems that he wanted to elevate the status of De anima to that of a special science among other natural disciplines that is the noblest and most precise of all natural sciences on which all the other parts of natural philosophy could rely. What in the medieval times had perhaps been considered to be part of metaphysics was now the most valuable part of natural philosophy. Following the Alexandrian tradition, Zabarella himself left the question of the immortality of the soul to the theologians, because it did not belong to natural philosophy, and since Aristotle, as a natural philosopher, had not been explicit about it (Kessler 2011, p. 52). It is, in fact, hard to be sure, whether Zabarella himself thought that the soul was mortal. However, in his commentary on Aristotle’s treatise On the Soul Zabarella tried at least to prove that Aristotle himself did not consider it immortal (Mitrovic 2009; Valverde 2012).