نشریه حکمت سینوی
پیاپی 43 (بهار و تابستان 1389)

Aristotelian logic (predicative logic) through direct translation and by virtue of Aristotle’s works, and Stoic – Megarian logic (conditional logic) through indirect translation and by virtue of some Latin texts of Galen, Alexander of Aphrodisias and Boethius belonging to the early centuries of Christion era was introduced into Islamic world. After two centuries of attempt to translate, exposition, ulterance and understanding the Greek logical heritage, with Ibn Sina “the period of innovation and originality began. Ibn Sina’s logical innovations and logics of innovation, in particular the two theories of “conjunctive syllogism” and “temporal modalities” that by attempts in two hundred later until khaje Nasir al _ Din tusi came to such a perfection and solid foundation that this period of logical investigations can be called as “Avicennian logic” or “logic of Ibn Sina” and one shouldemphasize on its importance and independence in comparison to Aristotelian and Stoic-Megarian schools. In the present article the author besides giving a brief treatment of the two above – mentioned theories, presents his reasons for proving of the idea of “Avicennian logic”.

Transcendence of Necessary Being as compared with possible beings and their imperfections which is taken from religious teachings is one of the most important theistic preoccupation of Muslim Philosophers. In the meantime, Ibn Sina has a more transcendental view compared with other philosophers, including Mulla Sadra. He believes in God’s separateness from the universe. The distinction between God and possible beings is so great that Bu Ali has called it a total difference. The origin of God’stranscendenee should be sought in common ontological foundations of Sheikh al-Rais with other philosophers and the origins of separation of necessary Being from possible beings must be seen in his special view about this matter. His discussions in general theology and his speculations in subjects such as being and quiddity, necessary and possible and their characteristics can be conceived as a preparing ground for God’s transcendence. But what has been a motive in Ibn Sina’s more transcendental view as compared with other philosophers is his pluralistic view towards creation and his rejection of special gradation. In such a view, God is separate and distinctive of other beings.In the present article first the common foundations of Ibn Sina with other philosophers in presenting a transcendental view towards God and in the following the grounds for formation a more transcendental image towards God in Ibn Sina’s philosophy will be considered

Foreknowledge in Ibn Sina’s point of view means the encompassing knowledge of the Most High to the whole creation with best order and according to the most gracious possible way. He calls the foreknowledge of God a source of emanation of the goodness throughout the world of creation and the order which has been created accordingly as best order. Ibn Sina considers the evil as a privation of something or nonperfection for abeing and divides beings into two groups:Pure good which is devoid of any evil and corruption; something that its goodness and benefit is accompanied by an accidental evil. For Ibn Sina, such matter in spite of the existence of evil which occurs because of them and accompanies them is considered good. Foreknowledge and divine emanation demands that in addition to pure goodness to create existents that have plenary goodness and little evil as well. In Avicennian theosophy evils neither have relation with being which is the ground of all goodness, norwith divine attributes and actions. In Ibn Sina’s philosophy any imperfections in the world of creation belong to the weakness and failure of material recipients in natural world. On this basis it can be said that the best possible order is an order that on the one hand has more perfection and goodness in vaster and higher perfection than in any other world, and on the other has fewer and more limited imperfections and evils (in the naturalworld).

Although stating explicitly the difference between de re and de dicto modalities, Ibn-Sina deals only with de re modality and its divisions, neglecting de dicto modality and its importance in Islamic philosophy. Among the uses of de dicto modality, one is predicating species on genus: in Ibn-Sina’s view, the proposition “animal is (a) human” is necessary orimpossible if human individuals are considered, but possible if human’s essence is considered. A proposition involving “the possibility of predicating species on genus” (such as “animal is possibly human”) lacks any name in ancient logic, so I name it “essential proposition”. It is not contained in the classical divisions in ancient logic because it is not any one of the singular, natural, indefinite, or quantified propositions, nor is it haml e awwali or haml e shaie. The secret of its being out of the classical divisions is that they areonly for abstract propositions and de re modalities, whereas it is not in principle a de re modality and has to be regarded as de dicto one.

Philosophers regard the problems of science as essential accidents of the subject of science and they call a predicate which a subject derived at the level of it and a predicate which is joined to it by essence and substance of a subject joined to it essential accident. Although the basis of this remark is taken from Aristotle, but philosophers such as Farabi and Ibn Sina have propounded new topics about the relation of the subject of science with the subject of a problem which can not be seen in Aristotle’s works. Since thepredicates of problems are the essential accidents of subject of science, the subject of science should be derived at the level of predicates of problems of science. But application the rule of essential accidents to all the problems of science is not without its difficulties. To solve this problem the concept of essential accident has been developed by Farabi and Ibn Sina with different elaborations and thereby the subjects of the problems besides the science includes matters such as kind of the subject of science, subdivision of kinds of the subject of science and essential accidents of the subject of science as well. Sheikh al- Rais for identifying the boundaries of this development hasset forth the standard of specification and mediation in predication. Ibn Rushd in his commentary and compendia of Aristotle’s works has paid no attention to innovations of Farabi and Ibn Sina and has no a consistent remarks in these matters.

In Islamic Philosophy and messengership are explained by two principles of reason and imagination. Ibn Sina has regarded the Prophecy as having three degrees.The first degree, which is devoted to the perfection of holy reason and the faculty of theoretical reason. The second degree is a particular characteristic of perfect imagination and finally is the Prophecy characterized by specific physical affections and locomotive faculties.He considers the perfection of imagination for the fulfillment of Prophecy as a sufficient requirement. The importance given to imagination in the explanation of the meaning of Prophecy can pay the way for entering of the personal imagination of the prophet into the area of revelation and receiving and transmitting it to others. But in the Philosophy of Sheikh al - Rais as long as the imagination is stronger, it can impart its impressions. On the one hand, if like Ibn Sina we regard the strength of locomotive faculties as another degree of Prophecy, then we have opened the way for this objection that anyone who attains to the perfection of imagination or the locomotive strength has attained to Prophecy. Whereas Ibn Sina believes that reception of revelation from active intellect through holy reason, conveying it to others a result of subtle impressions of strong imagination and declaration of miracles with the locomotive faculty, all sensual faculties in their perfect strength are the servants of rational faculty. Thus Ibn Sina shows that theperfection of imagination and locomotive faculties of prophet alongside the strength of intellect constitute a degree of Prophecy.

In Essentialism says: there re things which have essences and these essences do not depend on how we consider or call them. According to essentialists, everything is a complex of its essential properties which is called individual essence. These properties are distinct from accidental properties and independent from how we consider or call them. On thecontrary, a conventionalist does not believe in essences. According to him, athing’s essence is a mirror of how people consider or call it. According to Aristotle, individuals have essences and ousias which determine their whole reality. For Avicenna too, substances -and accidents- have essences which are independent from other things. In Aristotelian-Avicennian essentialism, knowledge and definition is just due to form and essence. While this tradition is mostly intended to solve the problems of knowledgeand definition, contemporary essentialism mostly discusses the problems of “identity” and “possible worlds”. In this tradition, an essential property of a thing is the one which is with the thing in any possible world.