I want to know the answer to the following question:
What subject is seen throughout Avicenna's Book of Healing?
All the background I'm provided with is that "Avicenna's legacy in classical psychology is primarily embodied in the Kitab al-nafs parts of his Kitab al-shifa (The Book of Healing) and Kitab al-najat (The Book of Deliverance).". Is that enough to answer the question?