Philosophers have always been interested in trying to understand the truth of the soul and its results. And it is considered as one of the concerns of their philosophical course. In this regard, they have provided many definitions of the soul. Some believed in the old and some in the new. And a group like Ibn Sina believed in the singleness of the soul at the beginning of creation and Sadra in the materiality of the soul at the beginning of creation. As Ibn Sina states, the occurrence of the soul is accompanied by the occurrence of the body, or in other words, the occurrence of the soul is "with the body". According to Ibn Sina, the human soul is intellectually single from the beginning of its nature when it occurs but in Sadra's view, the soul is first and foremost a material thing, and it is a hierarchical truth to which the body is a descendant. Accordingly, any interaction at any level is related to interaction at higher and lower levels. And finally, what caused the fundamental difference between the two peripatetic and transcendent wisdoms is the belief and disbelief in the movement of the substance, in the light of which this discussion takes on a new life.