Although the philosophical system of Ibn Sina is a purely intellectual one that many of its underlying principles is constituted by the principles of Aristotelian philosopy and his philosophy is called "peripatetic philosophy", but Ibn Sina never commits himself to the preservation of all the principles of Aristotelian philosophy and in many cases criticises them. By accepting some Aristotelian principles and presenting his own philosophical principles, Ibn Sina is considered the founder of Islamic prepatetic philosophical system which is a philosophy based on existent.He regards the object of his metaphysics existent qua existent and founds his metaphysical principles of the basis of that concept.Throughout the history besides Ibn Sina many of the philosophers after him as well in the Islamic world and in the west consider the object of metaphysic as existent qua existent, but it does not mean at all that all these philosophers have a single metaphysical structure. In the philosophy of Ibn Sina existent is a univocal concept which by anological gradution applies to its exemplifications. The concept of existent qua existent is so universal and comprehensive that all the objects in the universe are the extentions and denotations of it.The wide scope of existent qua existent include all creatures, from the blessed and exalted God to abstract possibilities and then corporeal possibilities and at last at the lowest level of existence, the primary matter.Among these existents God has a pure self subsitent existence, depends on no other being and by contrast possible being have a correlative and dependent existence on neccessary beings and in their existence and survial need neccessary being.