Secular Thought in the Islamic Golden Age The Golden Age of Islam is generally considered to be from the 9 th to the 12 th c AD or CE with the main centers at Baghdad, Bukhara and Damascus. The House of Wisdom in Baghdad was created by Harun Al-Rashid in the 8 th c whose main purpose was the translation of the Greek texts of Aristotle, Ptolemy and the Neo Platonists into Arabic, Persian and Hebrew. It also served as an academy for scholars from all over the Islamic world. This paper will attempt to give a feel for the contributions of perhaps the best known of these scholars -Ibn Sina (Avicenna) 980 to 1037 CE. Ibn Sina was born in a small village outside Bukhara which at that time was a thriving center due to its location on the Silk Road from China to the Levant. He was an autodiktat having little or no formal education but extensive access to the library of the Persian ruler of the region the Amir Ibn Mansur. He completed his first work The Compendium of the Soul at the age of 18. He was forced to flee to Khorezm in the North due to a Turkish invasion. By that time he had absorbed enough of the wisdom of his predecessors especially Al Farabi (d. 950 CE) to be assured of employment elsewhere and he spent the rest of his life as a peripatetic scholar eventually dying in Hamadan in Persia. Ibn Sina was an extraordinarily prolific scholar, writing in Arabic on Medicine, Philosophy, Physics, Metaphysics, Logic, Politics and Psychology. These were organized under a number of different Summa, the most famous of which was the monumental The Cure. His accomplishments had an lasting effect on both Islamic thought and later Medieval philosophy and theology, his works being translated into Latin which were to have a profound influence on Thomas Aquinas. Unfortunately his interpretations of Aristotle and Porphyry led to accusations of heresy by Al Gazali 1058 to 1111 CE and with the exception of the later Andalusian outlier Ibn Rashd marked the decline of intellectual advance in Eastern Islam. A little over a century later Baghdad was sacked and completely destroyed by the Mongols. The philosophy of Ibn Sina It should be clearly understood that in the 11 th c there was no clear distinction between philosophy and theology. Ibn Sina wrote at a time when the Greek translations had been organized into a school of Islamic theology known as Kalam to reconcile issues related to the suras of the Qur'an. One of the most orthodox branches was Ash'arism that rejected cause and effect reasoning. Falsafa (a loan word) was basically Aristotlean thought in an Islamic context and is exemplified by Al Farabi who stated somewhat bravely that religion is the imitation of Philosophy, its other exemplars being Ibn Sina and Ibn Rashd (Averroes) Given the huge scope of Ibn Sina's studies it seem that it would be most useful to limit this paper to his Natural Philosophy with some brief excursions into Ontology and Epistemology. Ibn Sina was mainly interested in explaining causality and the principles existing in Nature. He took the 4 causes: matter, form, agent and end from Aristotle. The material cause is a substratum of form and is attributed to the Giver of Forms. Ibn Sina expands Aristotle's categories to include both the 1
physical and the metaphysical, Such metaphysical causes are what determines existence and continuity (as concrete particulars) e.g a metaphysical agent is what gives species and form to matter, hence parents in procreation only prepare matter for the form and the substance of the same kind as the parents. Nature Aristotle did not try to prove the existence of nature but simply wondered if it was passive or active. Ibn Sina distinguishes between external causes and those particular to substance itself giving the example that water becomes hot due to the action of heat but becomes cool by itself. Motion may result from volition or not, uniformly or otherwise. Another example he gives is the motion of a magnet due to the proximity of a body of iron which may be misunderstood as an internal volition of the magnet itself as opposed to an externality. This empirical approach was criticized by Al Gazali (an Asherite) who argued that observations could not distinguish between a true causal connection and constant conjunctions (a point made by Hume much later) The contrary explanation from the Kalum perspective is the business of cotton catching fire when exposed to a flame. Is this the nature of fire or simply the will of God or his custom? Since God is omnipotent he has causal power over everything and impious ideas of nature are simply not necessary (as secondary causes). Nature then for Ibn Sina is an active cause that produces motion in the moved body. The nature of the substance is the immediate efficient cause of all of its characteristics both active and passive. Bodies Sensible or simple bodies are composed of either finite or infinite numbers of parts. Are these to be considered as distinct (internal) arrangements or potential as in surface edges or components. Parts according to Ibn Sina are units and are finite, since a body with an infinite number of parts would itself have to be of infinite extent. Bodies are active due to form and passive as a consequence of matter. Active motions may be circular or to or from the center. For terrestrial bodies there is only rectilinear motion. Celestial bodies natural motion is around the center (The earth being the center of the Ptolemic Universe) The 4 elements constitute nature, Fire and Air move up and Water and Earth down (per Hippocrates). The limits of natural division of bodies are limited by qualitative characteristics. Ibn Sina gives the example of a small quantity of water in a container which may be reduced to a natural minimum where the effect of the surrounding warmer air eventually overcomes the coolness of the water at which point the water becomes air (or we would say it simply evaporates). This leads to a question of exactly how far can parts or atoms be divided. The atoms of Democritus have shape that implies limits either conceptually or physically. In Kalum thought atoms were indivisible and their only characteristic is that they should occupy space. Ibn Sina argues along the following lines. Consider for the sake of simplicity a 2 D space populated with such Kalum atoms set out like a checkerboard. Construct an isosceles right triangle with equal sides of length 3 atoms. The correct length of the hypotenuse from Pythagoras is ~4.24 hence the conceptual indivisibility argument of Kalum fails for indivisible atoms. 2
Infinity Ibn Sina is very clear on the nature of infinity-it does not exist either as a quantity or as say numbers in a sequence (until Cantor came along). By contrast Kalum says there is no infinity apart from God as actual or potential. Ibn Sina illustrates his position with the following thought experiment. Consider two beams of light projected into space to an infinite distance. The both originate from the same point A at an acute angle to each other. Any equidistant points from A are point B on one beam and point C on the other. Now however distant A-B and A-C are, the distance between them is still finite, even at infinity. So the universe is either finite or a contradiction. Motion This is a difficult area in part due to the meaning of the Greek entelecheia. Is it actualization or actuality (outcome). Ibn Sina sees motion as perfection vs process. This he elaborated into traversal motion say a walk from point A to point B with a medial potential state at any point during the progress of the motion. The totality of the walk does not exist in the same way as say a measure of total distance A-B. The medial motion is the form that the body has when it is in motion and can explain its motion. ( Hope that is clear). He does not specifically refer to time but in considering motion over ever smaller distances we get down to instantaneous motion which he calls the first perfection. He also defines motion into two categories genus (difference) and species. He is not certain if it belongs as genus within the Aristotlean categories. As to species he defined quantity, quality and place, the later being the most primary. Changes in place are motion and motion with respect to position is exemplified in the spin of an orb, since quantity and quality remain fixed. This requires further explanation since motion implies start and end points, however the rotation of the heavens has no beginning or end and Ibn Sina thought they have neither. However noting the position of the sun overhead on successive days does mark a relative sequence of a beginning and an end state. Place, following Aristotle is the surface that is the extremity of the containing body and per Ibn Sina is intrinsic (essential) or extrinsic (accidental) to a body and he argues that a body's extrinsic nature is what it encompasses. What may lie between then? And Ibn Sina claims that voids are not possible since if it is nothingness then what is it? The quantity of a void may be more or less. This is argued in terms of accidentality associated with substance which needs to have corporeality and therefore existence. Or if essential then the quantity of the void needs be some (undefinable) species of quantity. Hence there can be no positive definition of void in terms of genus or difference. Time This was never clearly defined by Aristotle. Ibn Sina produces definitions based on motion: 1. Two moving bodies with the same speed start and stop at the same points then they travel the same distances. 2. If bodies have different speeds then the distance covered that they travel relative to fixed marks will differ. 3
Thus he concludes that the distance covered at a fixed speed is what we call time. Since he earlier defined circular motion in terms of prior and post events he contends it can be extended into both past and future. This addresses the question of the creation of the universe. Take some arbitrary time measured by rotations of the sun and assume that God made the world at some particular moment (along with the motion of all known bodies) By applying the same reasoning to some other finite time intervals in like manner he concludes time must exist including motion and bodies. And if nothing predated God then so would the framework of the universe- a clear contradiction. Therefore the only conclusion is that time existed infinitely back into the past. He goes further than Aristotle in asserting that God is not only the prime mover but he who gave being to the world. Ontology The distinction between existence and essence raises questions about the nature of God as part of existence. Ibn Sina suggests a distinction between the being of a thing and its existence. Hence it can be said that there is both existence and the reality of the thing its essence. Existence may be either mental or external. Essence is regardless of existence, the thingness of its character or modality that its existence has. Quiddity can be seen as a possibility whereas existence is necessity. In everything the difference between what a thing is and the fact that it is, is inevitable. But which is prior? Existence can therefore be be seen as external to essence. (a thing that does not exist or exists in imagination may have an essence) Necessity is an affirmation of existence and a cause allowing a transition or tendency from the possible to the necessary. Al Farabi taught that if essence preceded existence then we could end up with two different beings one prior and one post existence. Al Gazali said that God cannot be known as a simple existence without essence. Ibn Sina concluded that existence is an additional attribute to the essence of a thing which is, but essence is not a causal agent since it would have to cause itself. Further essence may be seen as a mental construct unrelated to existence as when man comes to be aware of his own existence, his self or consciousness is his essence. (but see Sartre) Epistemology Man according to Ibn Sina is born a tabla rosa. Knowledge is gained from empirical judgements from which are abstracted universal concepts. There is a transcendental intellect in which all essences and knowledge exist. God's knowledge is pure simple and immaterial, not specific and only applies to universals. Criticisms Al Ghazali published a work Tahafut al-falasifa The incoherence of the Philosophers directed at the falsafa of Al Farabi and Ibn Sina. He listed 20 objections of which the most serious errors were:- 1. The universe is eternal and not created in time 2. God knows universals not particulars 3. There is no resurrection of bodies only souls (since they are immortal) This along with the slow collapse of the Abbasid Dynasty marked the eventual abandonment of the secular tradition within Islam, the reinforcement of orthodoxy and historically the retreat into religious teachings in the madrassas and universities. The East's loss was the West's gain and Ibn Sina's ideas transmitted via Moorish Spain formed the broad basis for medieval Scholastic thought and Renaissance scholarship until the emergence of enlightenment scientific method and enterprise. 4
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