El. knyga: Aristotle's On the Soul: A Critical Guide

"We naturally think of the De Anima as belonging to psychology, whether more empirical or more philosophical. De Anima's declared subject, however, is the soul, considered as a source or principle of life-an animator. Thus the subject S to which De Animacontributes deals with souls quite generally. And because it does, it deals also with the animator of plants, which is nutritive soul (DA II.4). This marks one important difference between S and what we call psychology-one way in which S is aligned more closely with biology or botany. Moreover, Aristotle himself acknowledges that S is a divided or bipartite science,: There is a puzzle too about the affections of the soul, as to whether they are all also shared by what has the soul or whether there is also some attribute that is special to the soul itself. For it is necessary to attain [ a resolution of] this, but it is not easy. It appears that in most cases, though, the soul is neither affected by nor does it act without the body-for example, being angry, being confident, having an appetite for things, perceiving in general-whereas understanding seems to be most of all special to the soul. ... And this is why it already belongs to the natural scientist to get a theoretical grasp on the soul, either all soul or this sort of soul"--