The article continues our study of the reception of aristotelian psychology in the philosophy of the greatest thinker of classical Islam — Ibn Sina (Avicenna, 980– 1037), which has been begun in this journal (2021, No. 4). Endowing aristotelism with an immortological dimension, the Muslim philosopher transforms hylemorphism into entelechism, justiϐies the substantiality of the soul, its incorporeality and incorruptibility. In avicennian reconstruction of aristotelian treatise “On the Soul” primary attention is paid to criticism of the opinions on the soul as harmony or mixture, as well as to the interpretation of Stagirite’s thesis about the non-magnitudeness of mind in a sense of assertion about soul’s immateriality resulting from its status as a substratum of intelligibles. The article also highlights Ibn-Sina’s modiϐication of the relevant statements regarding the organs of the rational soul.