In this article, by an introduction about the importance of recognition of existence, I proceed to existence as a common subject between philosophy and gonastism. The subjects of existence is the most obvious concept and also the most comlex fact in metaphysics. In this article also pointed to the Molla Sadra"s views about the existance and his several profound questions about the significance and recognition of existence... seven reasons from the last chapter of Tahrir -al- Tamhid and reasonof piouses has been explained briefly. Another part of this article is the viewpoints of professor Assar about existence and Ayatolah Rafiee Ghazvini about the EXISTENT unity. This article is an introduction to the proposal of research about Ibn Arabi and late Imam Khomeyni" s viewpoints which we are going to explain them later.

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.

Generally speaking, Islamic philosophy is the legacy of Greece and is modeled on Aristotle's works in particular. Like the collection of his philosophical works, it consists of logic, general metaphysics, physics, theology, and practical wisdom. Concerning the definition and subject of philosophy, following the Aristotelian tradition, Islamic philosophy has referred to "EXISTENT qua EXISTENT" and "separate substances" and posed the discussion of whether each is separately the subject of philosophy, and whether they are the same as each other or one includes the other. Moreover, it asks how, if the former is true, this sameness is justified, and if the latter is true, which is general and which is particular.In all the philosophical systems of the East and the West, these two issues, that is, the accidents of EXISTENT qua EXISTENT and separate substances are mixed with each other and cannot sometimes be separated from each other. However, in Islamic philosophy, particularly after Mulla Sadra, they were separated from each other under the titles general theology and particular theology or theodicy. However, both are subcategorized under the all-inclusive title "prime philosophy" or theology. There have also been debate concerning the scientific borderlines between the two issues; nevertheless, they have not led to any conclusions in practice. This paper deals with a methodological demarcation between them.

growing process of Islamic philosophy handed it to Sadr al- Mutaallhin and his followers to guarantee its flourishing. The interdisciplinary which was published by Sadra resulted to guarantee the strength of other homogenous courses for his philosophy. Like this category is the gnostic interests and the applying of the real EXISTENT (haqiqah) and intangible EXISTENT (raqiqah) doctrine in order to solve the different issues of ontology, theist and self-knowledge. Presenting a coherent Weltanschauung (world view) is the result of the applying of this more effective issue in all high processing of Sadra and the followers of the transcendental philosophy (al-hikmat al mutaaliya). The expanded realm of this subject has extended to include epistemology And ontology of the self and in these key arguments and controversial subjects such as the unity of soul and body, the circumstance of creation of science, the knowing for self and its created (huduth) and eternal (qidam) and other coherent issues it has a crucial role.

It is known that Ibn Sina Has mentioned three arguments to prove the necessary of EXISTENT, that is the argument from causality, from movement, and the argument from necessity and possibility. With a little reflection, it becomes clear that none of these arguments are Ibn Sina's innovative demonstration and are clearly stated in the works of Aristotle, Kindi and Farabi. What is Ibn Sina's original demonstration in proving the necessity of existence is the argument that is requisite for his philosophical system, that is, the demonstration based on the rational analysis of "existence" which can be called the Ibn Sinai demonstration. Ibn Sina, by rational analysis of existence as rational truth, proves the being of necessary EXISTENT and divine attributes and actions. Whereas in the above three proofs, with the presumption of possible existence, God is proved. In this article, we show with arguments and the evidences that Ibn Sina's main and innovative argument is based on his theory about existence. Existence in Ibn Sina's thought is a metaphysical and a priori truth. contemplating on Ibn Sina's theory about existence makes it clear that his argument is not of Anselm and Descartes' argument and is not subject to Kant's criticism. On this basis, Ibn Sina is the first to present an EXISTENTial argument that, while preceding philosophers such as Anselm, is also significantly different from them.

There are principles in Islamic Philosophy which serve as evidence in favor of the view that Muslim philosophers understand Necessary EXISTENT to be “ personal” . The principles include “ division of beings into necessary and contingent while accepting univocity of existence” , “ The demand of Necessary EXISTENT for evidence” , “ univocity of Necessary EXISTENT’ s attributes and those of contingent beings” , “ application of personal beings’ predicates to Necessary EXISTENT” , “ understanding revelation as speech” , “ personal account of God in the course of prayer” , etc. There are, however, some other pieces of evidence that indicate impersonality of Necessary EXISTENT, e. g. “ Theory of Emanation” , “ pure simplicity of Necessary EXISTENT” , “ Infinity of Necessary EXISTENT” , “ Apophaticity in religious language” , and “ denial of independent existence of caused being” . The latter pieces of evidence show, at least, that there is an ambiguity in understanding whether the concept of Necessary EXISTENT in Islamic philosophy indicates an (im)personal God. At most, they demonstrate that the concept of Necessary EXISTENT in Islamic philosophy is more compatible with an impersonal notion of God. In this article, while giving some points on the strong claim, I shall argue for the weak one.

In the fourth subpart (namat) of Kitāb al-Ishārāt wa-l-Tanbīhāt, Ibn Sīna tries to prove the existence of a particular being, named “Necessary EXISTENT”. There he also explains the central role of this being in the world, His relation to other beings, and His attributes. It is in this very framework that he discusses other beings, that is, only to glorify the “Necessary EXISTENT”. Ibn Sīna believes that the “Necessary EXISTENT” is the cause of existence and makes things exist. In his ontology, the possible EXISTENTs, i.e. everything except the necessary being, are considered to be “caused”. In view of this, in the fourth subpart of Kitāb al-Ishārāt wa-l-Tanbīhāt as well, everything other than the “Necessary EXISTENT” has been taken into consideration only as a caused thing or an effect.

The problem of self- evidency of existence has been propounded in a content contrary, or at least unconcerned, to the theory of the reality of existence. But some scholars such as Riizl or Tusl have claimed self-evidency of EXISTENT. EXISTENT here has been interpreted as EXISTENTiality. If we accept the reality of existence and notice that this reality could not be found in the mind, we can conclude that we can only understand the implications of the EXISTENT not its reality. Its reality can be understood only in the Knowledge by presence. Knowledge by presence is not divided to concepts and propositions. So the meaning of self- evidency of existence is the self- evidency of existence's implications.

"Potentiality and actuality" is among the qualities of the absolute EXISTENT, which is the subject of First Philosophy. An EXISTENT is "potential" with respect to the actuality it can possess, though it is an "actual EXISTENT" by attention to the actuality it now possesses. It should be mentioned that potentiality is an EXISTENTial thing, however a weak existence which is distinguished from nonexistence. The present essay initially deals with the question how 'potentiality and actuality' entered First Philosophy. Then it proceeds to analyze the relation between such an issue and the subject of first philosophy as well as the how of application of existence to it. And finally, the paper propounds some dubious things and then responds to them.