Averroes

Ibn Rushd

A century before Averroes was born, the most influential theologian in Islam, al-Ghazali, wrote a book to destroy philosophy. He called it The Incoherence of the Philosophers, and it argued, with devastating skill, that the Greek-inspired thinkers who claimed to prove things by reason had wandered into outright unbelief, that their eternal universe and their distant, uninvolved God put them outside the faith, and that reason, pushed that far, collapses into contradiction. In much of the Islamic world the book did its work; it helped turn a whole civilization away from systematic philosophy. Then, generations later, in Muslim Spain, a judge and physician named Averroes wrote the reply, and he announced his intent in the title alone. He called it The Incoherence of the Incoherence. Point by point he took al-Ghazali's charges and answered every one, defending the philosophers, defending reason's right to inquire, defending the idea that the universe is intelligible and runs on real causes. It is one of the great duels in the history of thought, and the stakes could hardly be higher: whether a culture would trust human reason to understand the world, or decide that the attempt leads only to ruin.

Does anything really cause anything? The sharpest exchange in the duel is about a burning piece of cotton, and it reaches further than either man knew. When fire touches cotton, the cotton burns; we say the fire causes the burning. But al-Ghazali denied it. There is, he argued, no necessary connection between the fire and the burning at all; we see them go together, again and again, and lazily call the one the cause of the other, but all we ever actually observe is one thing and then a second thing. The real cause of the burning is God, who simply chooses to create the burning whenever fire meets cotton, and could just as easily decline. On this view nature has no powers of its own; there is only God, acting from moment to moment, and the regularities we trust are nothing but his settled habits. Averroes was appalled, and his reply is a defense of the intelligible world. To deny that things have natures and powers, he argued, to say that fire does not really burn, is to deny that things have definitions, and to deny that is to deny knowledge itself; a world without real causes is a world the mind cannot understand. The argument matters enormously, because a science is possible only if nature has its own reliable causes to be discovered. And the strange thing is that seven centuries later David Hume would look at the same burning cotton and side, in his own way, with al-Ghazali: that we never see the necessary connection, only the constant conjunction. The deepest problem in the philosophy of science was already fully alive in twelfth-century Córdoba.

Two ways to one truth. Averroes did not think himself an enemy of his religion; he thought himself its truest friend, and he made the case in a short, bold book cast in the form of a legal ruling. The Quran, he pointed out, repeatedly commands the believer to reflect, to consider the heavens and the earth, to reason; so the study of the world by philosophy is not merely permitted but commanded by scripture itself, for those with the capacity for it. And when a demonstrated philosophical truth seems to clash with the literal words of revelation, the answer is not to abandon reason but to read the scripture more deeply, because its surface was pitched for ordinary people who think in images, while its inner meaning agrees with what reason proves. There is one truth, Averroes insisted, not two; different people simply reach it by different roads, the crowd through vivid stories, the theologians through argument, the philosophers through proof. The Latins would later garble this into a scandalous doctrine of "double truth," as though Averroes had held that a thing could be true in philosophy and false in religion, but that was never his view. His view was bolder and more confident: that something demonstrated by reason and something revealed by God cannot finally conflict, because reality is one.

One mind for all of us. One Averroist doctrine went off like a bomb, and it rewards understanding, because it is stranger and deeper than the scandal it caused. Thinking about how universal concepts work, how "triangle" or "justice" can be the very same idea in your mind and in mine, Averroes reached a radical conclusion: that the intellect itself, the faculty that grasps universals, is not private to each of us but is a single thing, one shared mind in which all human beings participate. What makes my thought mine and yours yours is not the intellect, which is one, but the particular images and experiences each of us feeds into it. It is a strange idea, but not a stupid one; it neatly explains how we can all think the identical thought. The trouble was theological: if the intellect is one and shared, then there is no individual mind left to outlast your body, and personal immortality is gone. In the Christian universities this was intolerable; Aquinas wrote a whole treatise against it, and it became the centerpiece of the great Paris condemnation that tried to fence off the dangerous parts of Aristotle. But the doctrine has never quite died, because the question beneath it is real and still open: when two people genuinely grasp the same truth, what exactly is the thing they share?

Lost at home, crowned abroad. Averroes's story has an ending of extraordinary irony, though the irony is about ideas more than about the man. In his own civilization, he lost. A political turn against philosophy in his later years brought him a spell of disgrace; more lastingly, the Islamic world, persuaded by al-Ghazali, was turning away from the kind of systematic rational philosophy Averroes embodied, and after him the great tradition of Arabic falsafa faded as a living movement. And then, just as he was being forgotten by his own, he was discovered by his rivals. His commentaries on Aristotle, translated into Latin, reached the new universities of Christian Europe exactly as they were straining to absorb the flood of Aristotle, and they were a revelation. For the next four hundred years Averroes was simply "the Commentator," the indispensable guide to "the Philosopher," read and argued with by everyone from Aquinas to the professors of Renaissance Padua. A Muslim judge from Córdoba became one of the most important teachers the Christian West would ever have, honored by the civilization that was not his and sidelined by the one that was.

Why the duel still matters. The room reads Averroes in an older translation of his defenses of philosophy, cited by work and section; the great commentaries themselves survive in English only under copyright, so the chat works from the wider record where it must. What makes him matter now is less any single doctrine than the thing he stood for, at real cost, in a culture that was deciding to stop trusting reason. He believed that the world is the kind of place a mind can understand; that things have real natures and act by real causes; that revelation and reason, rightly read, point the same way; and that to give up on rational inquiry out of fear of where it might lead is to give up on the world's intelligibility itself. He happened to lose that argument in his own time and place, and the cost of philosophy's retreat there was long and real. It is hard to read him, in an age with its own loud suspicions of reason and expertise, without sensing that the argument he was making never quite ends, and that which side a civilization takes still decides a great deal about what it will be able to know.

There is a poignancy in Averroes that outlasts his arguments. He was a working judge who spent his nights recovering, defending, and clarifying the thought of a pagan Greek dead fifteen hundred years, convinced that to think clearly was itself a kind of devotion and that no honest use of the mind could be an enemy of the truth. He could not have known how it would come out, that his books would be burned by some and canonized by others, that he would lose his own world and conquer a foreign one, that a line of Christian friars would carry his reading of Aristotle into the universities from which, in time, modern science would grow. He only did the work in front of him, which was to insist, against a rising tide, that the world is intelligible and the mind is built to understand it. That remains one of the bravest things a person can insist on, and one of the most necessary.