Ibn Sina, Abu ‘Ali al-Husayn

(370–428/980–1037)

   Born near Bukhara, Ibn Sina – or ‘Avicenna’, as he was known to the Latins – may very well be the most important and influential thinker, not just of the Neoplatonic- Aristotelian (mashsha’i) school of Islamic philosophy in particular, or of the classical period of Islamic philosophy more generally, but of the whole Islamic philosophical tradition. His life as well as his thought is the stuff of legend. A precocious youth who frequently outstripped his teachers in the course of an ambitious and comprehensive education, Ibn Sina is said to have mastered all the known sciences by the age of eighteen. As a physician and political advisor during an unstable time, his adult life was filled with practical and sometimes dangerous worldly endeavors that often made it difficult for him to record his own original thoughts. Yet in spite of this, he was a prolific writer, penning hundreds of works on medicine, mathematics, the natural sciences and philosophy, as well as in Islamic sciences such as Qur’anic exegesis. Among his medical writings, his foremost contribution was the magisterial Canon of Medicine (Qanun fi al-tibb), which for at least six centuries was considered the definitive text in the field throughout both the East and the West and is used even to this day. His two major philosophical works are the encyclopedic Healing (al-Shifa’) and Directives and Remarks (Isharat wa al-tanbihat), which range in subject from logic to physics to mathematics to metaphysics to mysticism. His Deliverance (al-Najat) provides, as it were, a ‘Reader’s Digest’ condensed version of The Healing, while the Book of Knowledge (Danish-nama-yi ‘Ala’i) offers yet another concise presentation of Ibn Sina’s system – this time written in Persian – which al-Ghazali used as a template for his Intentions of the Philosophers. Although Ibn Sina made major contributions to virtually all the areas of philosophy, he is particularly known for his insights in the field of metaphysics. His complex and original system might be said to revolve around two chief insights. The first is that we have a basic, preconceptual intuition of being, rooted in an a priori awareness of our own existence unmediated by sense experience. Ibn Sina’s ‘floating man’ thought experiment, which illustrates this idea nicely, is ultimately intended to illustrate the substantiality of the soul (since it can conceive of itself independently of any reference to the body). But it also points towards the centrality of intuition (hads) in Ibn Sina’s epistemology (a power that makes demonstrative reasoning possible, inasmuch as it enables us to hit upon the middle term of a syllogism) and the fundamental unity of being and knowledge in his overall philosophy. Ibn Sina’s second chief insight is that the mode of our own existence (and of every other existing thing in the universe) is not sufficient unto itself; that is, it requires a more fundamental being to actualize and sustain it. In Ibn Sina’s terminology, human beings (and all such finite existents) are merely possible or contingent (mumkin) rather than necessary (wajib) in themselves, which means that although they do exist, they could just as easily not exist. Ibn Sina’s point here is ontological rather then simply temporal. It’s not simply that there was a time when a particular tree (for example) did not yet exist and that there will come a time when it no longer exists; the point is rather that even while the tree exists, its mode of existence is dependent, insofar as it is conditioned and determined by other causes. Put differently, we could say that no contradiction or absurdity is involved in conceiving of a merely possible being as non-existent (its existence is not ‘hard-wired’ into it, so to speak). Ibn Sina articulates this insight through his influential distinction between a thing’s essence or quiddity (mahiyya, lit. ‘whatness’) and its existence (wujud). In worldly, contingent things, there is no necessary connection between these two aspects; existence is a kind of accident, something superadded to an essence, which actualizes it and grants it being. Ibn Sina’s argument for the existence of God is essentially an attempt to explain the puzzling existence of composite, contingent beings. By their nature they must depend upon other beings for their very existence. Yet merely possible beings cannot ultimately be caused by other merely possible beings, for in and of themselves they do not possess existence. Such a causal chain could go on indefinitely without ever explaining the bare existence of even one contingent entity. The only way to render the fact of contingent being intelligible is to posit the existence of a First Being whose mode of existence is not merely contingent. That is, we must posit the existence of a Necessary Existent (wajib al-wujud), a being whose non-existence is by definition inconceivable, whose essence and existence are one and the same. This is Ibn Sina’s conception of God.

   Ibn Sina’s novel way of understanding the relation between God and the world enabled him to navigate a middle path between the dilemma of the falasifa’s eternal universe and the theologians’ temporally originated world. The former seemed to imply that the universe was necessary in and of itself (since it always had been and always would be), thus rendering God superfluous as an existential explanatory principle. For this reason it was often associated with materialism and atheism. The latter faced a multiplicity of serious conceptual problems in positing a beginning to time caused by an ostensibly eternal God. Ibn Sina’s new conception of God – as the ontological ground of an eternal but contingent universe – seemed to preserve the best aspects of both eternalism and creationism without getting bogged down in their respective problems. Ibn Sina’s cosmology retains an unmistakably Neoplatonic cast, however. For him, the event of being is not a function of God’s free, creative will, but rather is an automatic product of God’s selfknowledge, which generates a complex hierarchy of intellects (the tenth and last of these being the active intellect, which gives rise to the terrestrial world and serves as a link of sorts between human intellect and the divine). This process of emanation is not temporal, but logical: reality unfolds syllogistically. This insures its intelligibility, but it also means that the relation between cause and effect is necessary, much like the relation between premises and a conclusion is. Thus, while the universe and everything in it is merely possible or contingent in itself, it is also necessary through another (i.e. as an effect in relation to its cause). Which is to say that things cannot be other than they are. This seems to commit Ibn Sina to a deterministic model of the universe that constrains (or redefines) divine freedom just as much as it does human freedom.

   Grasping the intelligible structure of reality – and achieving knowledge about the existence and nature of its First Cause, God – has a salvific effect on the soul, enabling it to purify or perfect itself, and ultimately reascend to its ontological source. Ibn Sina argued for the immortality of the rational part of the soul (a point on which Aristotle was at best vague), but, contra the Neoplatonists, he also rejected its pre-eternity. He retained the Qur’anic notion of the resurrection (ma‘ad, lit. ‘return’), but interpreted it figuratively and intellectually, as he did the promise of reward and punishment. These views reflect Ibn Sina’s concern, which was greater than that of his mashsha’i predecessors, with remaining true to the religious particularities of Islam (prophecy, revelation, the hereafter, mystical experience), while still interpreting them in a philosophically respectable manner.

   There is in fact a hotly disputed question as to whether or not Ibn Sina himself was a mystic. A few of his books (most of which are now unfortunately lost) suggest that he formulated an alternative, indigenous system – an ‘Eastern philosophy’ or ‘Oriental wisdom’ (al-hikmat al-mashriqiyya) – which emphasized intuition over demonstrative proof, admitted mystic forms of gnosis, and was intended to complement or even supersede his Neoplatonic-Aristotelian system. While the case for reading Ibn Sina as a kind of proto-Illuminationist thinker is by no means clear-cut, it is at least safe to say that Ibn Sina had a healthy respect for mystic ways of knowing, even if he looked in on them from the perspective of an outsider.

   Ibn Sina’s influence far exceeded his eminent status within the mashsha’i tradition of philosophy. He was the definitive thinker to target when the theologians mounted their decisive attack on philosophy. It is often said that al-Ghazali effectively brought an end to the style of philosophy that Ibn Sina exemplified, but the truth of the matter is more complex. There were of course subsequent philosophers who continued in the mold of Ibn Sina, such as al-Tusi. But perhaps even more importantly, the philosophical theology of later Ash‘arite thinkers like al-Ghazali, al-Shahrastani and Fakhr al-Din al-Razi would – ironically – be virtually unthinkable without Ibn Sina, whose terminology and method of demonstrative proof they appropriated. The same could be said for the school of Illumination; despite its vocal opposition to the ‘Aristotelian’ style of reasoning, figures like al- Suhrawardi were deeply indebted to Ibn Sina’s ‘Eastern philosophy’ and emphasis on intuition, as well as his analysis of the relation between essence and existence. Ibn Sina’s impact outside the Islamic tradition is widely recognized, and can be seen clearly in the thought of crucial thinkers such as Ibn Maymun (Maimonides) and Aquinas.

   See active intellect; afterlife; Aristotle; causality; Eastern philosophy; epistemology; essence and existence; al-Farabi; floating man argument; free will and predestination; al-Ghazali; Ibn Rushd; Illuminationism; metaphysics; Mulla Sadra; mysticism; Neoplatonism; philosophy; prophecy; psychology; al-Suhrawardi

   Further reading: Goodman 1992a/2006; Gutas 1988; Ibn Sina 1952/81, 1973/2001, 1974, 1984, 1985, 1996, 2005; Janssens 2006; Marmura 2005; Nasr with Aminrazavi 1999; Wisnovsky 2003