Just as He——said [in the prophetic tradition]: "People are mines like the mines of gold and silver," until the degrees in loftiness culminate in annihilation within the Essential Unification (al-fana' fi al-tawhid al-dhati). And the appetitive soul (al-nafs al-shahwaniyyah) is the subtle vapor carrying life, sensation, and voluntary movement; it is that which the sages call the animal spirit (al-ruh al-hayawani), and it is a radiant substance.

Upon the body. For if it shines upon the outward aspect of the body and its inward aspect, wakefulness occurs; and if it shines upon the inward aspect of the body but not upon its outward aspect, sleep occurs; and if its shining is entirely severed from the animal, death occurs. So Glory be to the Wise Creator (al-Sani').

As for the rational soul (al-nafs al-natiqah), it is a substance abstract from matter in its essence, associated with it in its actions. And this soul is that which is named the commanding (al-ammarah), the self-reproaching (al-lawwamah), the inspired (al-mulhimah), the tranquil (al-mutma'innah), the pleased (al-radiyah), the well-pleasing (al-mardiyyah), and the perfect (al-kamilah).