From Faculties to Functions: Fakhr al-Dīn al-Rāzī’s Critique of Internal Senses

One of the basic questions of the classical theory of soul is the theory of internal senses. It is Avicenna who gave this theory its most elaborate form. While he effectively revised the theory of internal senses that he inherited as it was laid out, he expounded upon it along his own philosophical inclinations, making significant additions on intricate matters like the number and appellation of internal senses, introducing new distinctions and classifications. Over time, Avicenna’s novel framework concerning the theory drew several criticisms by his successors. An important critique against Avicennian theory of internal senses was leveled by Fakhr al-Dīn al-Rāzī. The first point of al-Rāzī’s contestation would be the critique of the arguments for the existence of each internal sense as a separate faculty. Al-Rāzī supposes that soul could perceive all objects of perception without recourse to independent faculties each designed for a separate function. Second, he criticized the narrative that plotted the brain for internal senses. While Fakhr al-Dīn al-Rāzī’s critique of the internal senses comprise the main subject of the current study, it will also try to clarify the aspects of this critique related to greater epistemological and psychological questions like the nature of the soul, the character of the relation and interaction of soul and body, the nature of perception, degrees of abstraction, the relation of the soul with the particulars and its bearing on them.