The Incoherence of the Philosophers

Al-Ghazâlî was one of the most prominent and influential philosophers, theologians, jurists, and mystics of Sunni Islam. He was active at a time when Sunni theology had just passed through its consolidation and entered a period of intense challenges from Shiite Ismâ’îlite theology and the Arabic tradition of Aristotelian philosophy (falsafa). Al-Ghazâlî understood the importance of falsafa and developed a complex response that rejected and condemned some of its teachings, while it also allowed him to accept and apply others. Al-Ghazâlî's critique of twenty positions of falsafa in his The Incoherence of the Philosophers (Tahâfut al-falâsifa) is a significant landmark in the history of philosophy as it advances the nominalist critique of Aristotelian science developed later in 14th century Europe.

His 11th century book The Incoherence of the Philosophers marks a major turn in Islamic epistemology, as al-Ghazali effectively discovered philosophical skepticism that would not be commonly seen in the West until René Descartes, George Berkeley and David Hume. The encounter with skepticism led Ghazali to embrace a form of theological occasionalism, or the belief that all causal events and interactions are not the product of material conjunctions but rather the immediate and present will of God.

On the Arabic and Muslim side, al-Ghazâlî's acceptance of demonstration (apodeixis) led to a much more refined and precise discourse on epistemology and a flowering of Aristotelian logics and metaphysics. With al-Ghazâlî, begins the successful introduction of Aristotelianism or rather Avicennism into Muslim theology. After a period of appropriation of the Greek sciences in the translation movement from Greek into Arabic and the writings of the falâsifa up to Avicenna (Ibn Sînâ, c.980–1037), philosophy and the Greek sciences were “naturalized” into the discourse of kalâm and Muslim theology. Al-Ghazâlî's approach to resolving apparent contradictions between reason and revelation was accepted by almost all later Muslim theologians and had a significant influence on Latin medieval thinking.

In the next century, Averroes (Ibn Rushd) drafted a lengthy rebuttal of Ghazali's Incoherence by another book entitled The Incoherence of the Incoherence; however, the epistemological course of Islamic thought had already been set by al-Ghazali and accepted by the Muslim world.

Extract below is taken from The Incoherence of the Incoherence, being the rebuttal by Ibn Rushd to The Incoherence of the Philosophers by Imam al-Ghazali, both books sitting on my bookshelf for the last 10 years, yet to be understood:

The Incoherence of the Philosophers:
The philosophers say: It is impossible that the temporal should proceed from the absolutely Eternal. For it is clear if we assume the Eternal existing without, for instance, the world proceeding from Him, then, at a certain moment, the world beginning to proceed from Him - that it did not proceed before, because there was no determining principle for its existence, but its existence was pure possibility. When the world begins in time, a new determinant either does or does not arise. If it does not, the world will stay in the same state of pure possibility as before; if a new determinant does arise, the same question can be asked about this new determinant, why it determines now, and not before, and either we shall have an infinite regress or we shall arrive at a principle determining eternally.

The Incoherence of the Incoherence:
This argument is in the highest degree dialectical and does not reach the pitch of demonstrative proof. For its premisses are common notions, and common notions approach the equivocal, whereas demonstrative premisses are concerned with things proper to the same genus.

For the term ‘possible’ is used in an equivocal way of the possible that happens more often than not, of the possible that happens less often than not, and of the possible with equal chances of happening, and these three types of the possible do not seem to have the same need for a new determining principle. For the possible that happens more often than not is frequently believed to have its determining principle in itself, not outside, as is the case with the possible which has equal chances of happening and not happening. Further, the possible resides sometimes in the agent, i.e. the possibility of acting, and sometimes in the patient, i.e. the possibility of receiving, and it does not seem that the necessity for a determining principle is the same in both cases. For it is well known that the possible in the patient needs a new determinant from the outside; this can be perceived by the senses in artificial things and in many natural things too, although in regard to natural things there is a doubt, for in most natural things the principle of their change forms part of them. Therefore it is believed of many natural things that they move themselves, and it is by no means self-evident that everything that is moved has a mover and that there is nothing that moves itself.; But all this needs to be examined, and the old philosophers have therefore done so. As concerns the possible in the agent, however, in many cases it is believed that it can be actualized without an external principle, for the transition in the agent from inactivity to activity is often regarded as not being a change which requires a principle; e.g. the transition in the geometer from non-geometrizing to geometrizing, or in the teacher from non-teaching to teaching.