Abstract

By a primitive analysis of material objects, Aristotle concluded that they consist of two components rather than one. One of them is matter and the other is form. Matter or hyle enjoys faculty and form enjoys actuality. The actions and reactions, as well as the frictions, between them create motion. This he defines motion as the objects gradual coming out of actuality and moving toward actuality.The importance of the principle of the distinction between matter form was so much that in the light of which Aristotle managed to clarify his other philosophically complicated theories. Dividing existents into sensibles and disengaged entities, explaining the distinction of disengaged existents form material ones, expounding actuality as the natural agent, interpreting possibility or preparedness possibility, introducing God as the Primary Unmoving Mover, and qualifying Him with form, pure actuality, quiddity, and substance are among the most distinctive achievements that he has had following accepting the principle of matter and form and disseminating it all over the world.However, influenced by religious teachings and because of believing in God's being the creator and the world's being the created, Ibn Sina claims that the world is essentially originated and one must not suffice to matter and form when interpreting the world. As a result, in addition to the two material and formal components, he speaks of a third component called existence.Therefore, the principle of the distinction of existence from quiddity turns into a basic principle and extending it the chain of worldly existence, Ibn Sina had a number of great achiements including dividing existence into the necessary and the possible, interpreting making activity and possibility as essential possibility, presenting of the argument of the believers, posing the argument of necessity and possibility to demonstrate the necessary, and qualifying the Necessary with a pure existence free from quiddity and substance.In line with a comparison of the above-mentioned two principles in Aristotle and Ibn Sina;s philosophies, we can compare some other philosophical principles and concomitants. Therefore, we must say that Aristotle divides existents in to substances and accidents while Ibn Sina divides them into necessary and possible existents. However, when analyzing the possible into two quiddative and ontological components, he considers substance and accidents as the different kinds of the quiddative component. Moreover, activity and possibility in Aristotle's philosophy are used in the sense of natural agent and preparedness possibility. Nevertheless, they are sued in the sense of making agent and essential possibility in Ibn Sina's philosophy.The argument employed to demonstrate God's existence in Aristotle's philosophy is the argument of motion, but it is the argument of the believers in Ibn Sina's philosophy. Aristotle's God is pure actuality and substance, whereas Ibn Sina's God is a Pure Existence free from substance and quiddity.