Aristotle is considered by many to be the founder of 'faculty psychology'--the attempt to explain a variety of psychological phenomena by reference to a few inborn capacities. In The Powers of Aristotle's Soul, Thomas Kjeller Johansen investigates his main work on psychology, the De Anima, from this perspective. He shows how Aristotle conceives of the soul's capacities and how he uses them to account for the souls of living beings. Johansen offers an original account of how Aristotle defines the capacities in relation to their activities and proper objects, and considers the relationship of...