عنوان مقاله [English]
According to Aristotle and his followers time being an essential concept is the quantity of the movement of atlas sphere. Being one of the Aristotelian categories, it occurs with bodies through movement. In the light of his substantial movement, Mulla Sadra proceeds from 'essential time' to 'substantial time'. Time is not among accidental essences nor is it an entity independent of material substances. It is instead the essential constituent of a material substance. That is why all material substances have their own particular timings. Time is the quantity of substantial movement existing together with substantial movement through the same body. In the light of his theory of relativity, Einstein, given that light travels with a constant speed, considers time as relative regarding it as the fourth dimension of a body necessary for the exact evaluation of events. Mulla Sadra sees eye to eye with Einstein on matters like extendedness of time, relativity of time, the fact that each object has its own timing and that time is the fourth dimension of a body, though Sadra looks at issues metaphysically whereas Einstein evaluates things physically. A physical approach, being empirical is deducible from empirical facts whereas a metaphysical approach is not empirical. Einstein's theory of time is related to accidental movements particularly spatial movements saying that there will be no place for time if there is no accidental movement. In addition to accidental movement, Mulla Sadra is, however, aware of substantial movement believing that time is the quantity of substantial movement.