Motion, is gradual exit of object from potentiality to action. In various positions of Asfar, Molla Sadra, speaks about the necessity of movement to a gradient. There are, in Malle sadra's view, two kinds of movement: accidental movement and substantial movement. In accidental movement, motion needs a subject which is composed of mā bi al- quwwa (what is potential) and of mā bi al- fi'l (what is actual), which is the substance. In accidental movement, therefore, we need an indelible object, which is substance. And after creating an object, motion occurs to it. But in substantial movement we do not need such subject, as the motion is in sustance and created by simple fiction not by synthetic one. Metaphysics, then, invent the existence and the existence is like that we can abstract the movement. In substantial movement, therefore, we do not need an indelible object for motion. In this article we try to survey this questions according to Malla Sadra's view.
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