نشریه حکمت سینوی
پیاپی 41 (زمستان 1387)

Acceptance the philosophical rule of unity (or the One) and belief in a unitary ground for all multiple creatures leads philosophers to the problem of the nature of emanation of multiplicity form God who is one from all respects. Peripatetic philosophers like Ibn Sina in response to this problem have proposed a well-known theory about the order of universe. In contrast, Muslim theologians (in particular, Fakhr Razi) with religious motives have opposed both this rule and philosophical views about the order of existence. Khajeh Nasir al-Din Tusi in his works by establishing the rule of one and in response to the criticism of opponents supports the theories of philosophers like Ibn Sina. However, in some of his works, Mohaghigh Tusi offers his own utterance. He believes that from the one, for the reason that it is one, emanates nothing except one, but emanation of multiple beings from a single ground with different aspects is possible. In his works, Mohaghigh Tusi carefully formulates the causal orders of creatures. In the first order a being emanates from the Most High and in the second order there are two beings which one of them has emanated from the first ground. In the following orders in addition to creatures which themselves have emanated from the Most High, become the source of different things, also special creatures emanate from the ground of the Most High.

Alongside with his philosophical studies, Ibn Sina has dealt with nature in order to gain a firm knowledge of nature and discovering scientific rules which govern it. Ibn Sina's view of nature, as a stage in infinite orders of existence which in a longitudinal order (on the basis of cause and effect) reaches to necessary by-itself, has been a major factor that his study of nature to have a religious tinge. Although as a experimental scholar he has used the method of induction and objective observation, but metaphysical principles in peripatetic philosophy has been a dominant element is his mind, and in different stages experimental method has played its own role. Therefore Ibn Sina's study of nature is not merely a result of method of induction and objective observation, but by completing the method of induction through rational argument he has produced certain propositions and has discovered scientific laws.He repeatedly points to sensual perception and imperfect induction and insists on the necessity of benefiting from intellect for supplementing this understanding and attainment of certainty. The aim of this article is to examine the method of Ibn Sina in knowing nature; for this purposed I have made use of what he has propose in his logical and philosophical (epistemology) discussions about empirical science or experimental method as a means of obtaining definitive knowledge concerning nature.

The habit of using well - established terms in traditional debates of a science makes people to have this attitude that also in daily and current discussions of that science these terms are always used with the same meaning. This opinion in many cases brings about error and mental perversions. Among the sciences in which the possibility of such a problem seriously exists is science of logic. Description and analysis of conditional propositions in Ibn Sina's logic and his followers shows these points. First, although non – predicative propositions have been designated as "conditional propositions" but habitual and literal concept of condition has no any necessity and certainty in the realization of this kind of propositions. Secondly, common criterion of being conditional among conjunctive and disjunctive propositions is indicative of a conviction to the possibility in the kinds of this division in Avicennian logic. With these two foundations, the scope of the extent of conditional propositions can cover all kinds of compound propositions in modern logic. Such an extent can be regarded as a good ground for this proposal: the term "conditional" in the subject of Avicennian logical propositions can be considered as an equivalent of the term "compound" in discussion of compound proposition in modern logic.

Suhravardi regards a good grasp of peripatetic philosophy a prevequisite for dealing with illuminative wisdom and all his works except "Illuminative Wisdom" are mainly concerned with Ibn Sina's teachings. In his discussion of the nature of soul he has the same approach. On the problem of inner perceptions he criticizes in his "Illuminative Wisdom" the five faculties that Ibn Sina has put forward rational conceptualization. But in his symbolie stories he states all the attempt and holy struggle of wayfarer for the liberation from bodily prison. In all cases that he speaks of inner perception, he has used symbols for the five senses of Ibn Sina. Since the external senses are proposed both before and after the internal senses, all these symbols are tenfold: ten birds, ten angels, ten graves, five towers, five cells and five gates.

Action and reaction of human soul in perception and intellection that is without doubt one of the most fundamental and oldest problems of philosophy goes by the name of active intellect in the philosophy of Aristotle. This designation in the history of Philosophy after Aristotle is interpreted from two points of view: natural and illuminative. The first view considers both active and passive intellect inherent in human soul, and like all creatures in natural world, it regards the evolutionary process of human spirit as coming out from the stage of passivity and receiving to the dimension of activity. By contrast, the second view allocates the passive aspect of intellect to human being and ascribes the active aspect to the order of Godhead this view regards the actuality of intellect as an emanation and divine illumination. In spite of a gap between the two view about the reference of intellect's activity, both view inevitably agree on this point that is beyond the will and power of human being and consequently speculative evolution of man's soul is an involuntary and deterministic matter. Contrary to these two customary exegesis, Islamic Prepatetic Philosophy of Farabi and Ibn Sina by ascribing the aspect of intellect's activity to two faculties that have come into being by a separative substance by the name of active intellect as well as intention and volition they succeed to propose a third view in the theory of active intellect that in spite of the assertion with the implication of the influence of a separative agent of the process of intellection, to explain the voluntariness and intentionality of speculative evolution of human soul.

Final perfection of human being is his progressive movement is to attain to the threshold of the Most High, and this in itself is his perfection and goodness, because human being whom God has created as His image has so high a dignity that as the most noble creature among possible beings can posses the attributes of the Truth and imitating the moral of the Truth. In Ibn Sina's view, mystic is a person who has turned his attention to the saceed world so that the light of the Truth continually shines on his inner being. Ibn Sina regards asceticism and worship as a preparation for mystical journey. He calls the first phase "volition" that he interprets as desire and inclination and considers its origin as demonstrable certainty and heart's inner faith. According to him the second phase is "asceticism" which means piety and doing hard works by suffering pain in the way of self-discipline. In Ibn Sina's view, after traveling the following phases, that is time, deep penetration, tranquility, fear and concealing, quietude, providence and ascent, the wayfare reaches a state where he has a glimpse of the Most High and sees himself as a mirror of Him. Finally the mystic, who is now united with God, at the end of this journey attains a state where he only sees God.

One of the most important parts of Aristotles Philosophy is devoted to theology or subjects pertaining to our Knowledge of God. Aristotle regards God as the first cause of movements of the universe, but considers him exonerated of any motion.The important point is that Aristotle's God is not the final cause of the world's movement and has no creative aspect.Aristotle in the Book of Lambda (the tenth book of Metaphysics) has proved the existence of Unmoved Mover and attempts to explain its attributes. This part of Metaphysics has been examined and interpreted by great peripatetic philosophers.On the basis of an a priori proof and by the observation of empirical movements in the world, Aristotle proves the existence of Unmoved Mover and holds that he has attributes such as all – knowing, being alive and goodness. Themistius, Ibn Sina, Ibn Rushd and Aquinas on the basis of differences they have on the grounds of their religious and philosophical belief, have commented on this part of Metaphysics. In some cases these commentaries have something in common and in others they are different form each other.