  Zabarella, then, did not give one decisive criterion according to which all arts and sciences could be arranged into one single hierarchy. However, when dealing with the place of the science of the soul among the other sciences, Zabarella gives an description of the nobility of this part of natural philosophy. Zabarella opposed the definition of the science of the soul as a middle discipline between physics and metaphysics. He states that Aristotle did not only wish to compare the science of the soul with other sciences, but to compare it with other parts of natural science. In Zabarella’s view it is obvious that the science of the soul is the most noble part of natural philosophy, the king and emperor of every other part, which are all dependent upon it, because it shows the first cause and the sum of everything that is in animals and in plants. The science of the soul is more exquisite and certain than all the parts of natural philosophy, because the causes of the science of the soul are more exact, not only to us, but also according to nature (Mikkeli 1997, p. 220).