A Shift Toward Science in Philosophy – Aristotle greatly valued scientific explanation and was more empirical than Plato, even though Aristotle does not have a modern view of matter. For him, any theory of human nature must include nutrition, respiration, and digestion (59).
Aristotle’s View of the Psyche Not Equal to Immaterial Soul – Because for Aristotle psyche [ψυχη] is something that all living, animate beings have (even plants), it is a mistake to equate Aristotle’s notion of the psyche with non-material views of the soul (via Christian theology) or mind (via the mind vs. matter problem), even though psyche is often translated “soul” and used in Christian writings this way (59).
Aristotle’s Notions of Form and Matter – In Book II of On the Soul, Aristotle articulates his theory that every living body is both form and matter. The form is the psyche and identifies what the living thing essentially is. The matter is the stuff out of which it is composed. Yet, Aristotle denies that form and matter and independent things. Describing a bronze sphere via form, it is a sphere, described via matter, it is bronze. On the one hand, the form is the sphere itself, not some non-material universal form as Plato would have described it. On the other hand, one cannot reduce the sphere to mere matter (i.e. the bronze) in the way some of the pre-Socratics would (60). Similarly, human beings are only one thing: persons. Described via form, they are a special kind of psyche identified by essential and distinctly human functions. Described via matter, persons are flesh and bone. Neither the form nor the matter should be thought of as separate substances, but as two aspects of an indivisible unity called “human.” This, according to Thomson and Missner, cuts across the grain of dualist (mind/body) and materialist accounts of reality. In contemporary terms, we might say a person can be described physically as flesh and bone, or psychologically in terms of what the person wants, believes, hopes, feels and does (61).
I am not an expert in Aristotelian philosophy, and therefore, I do not know whether this interpretation of Aristotle is unique and controversial, or generally agreed upon.