Justified True Belief

(●) The Muslim theologian who took the Greek philosophers apart, and left behind an argument for the Creator that Christians still use. + Abu Hamid al-Ghazali held the most sought-after teaching post in the Islamic world before he was thirty-five, and then walked away from it. He spent eleven years wandering, praying, and writing, and when he came back he was one of the most widely read religious authors Islam has produced. Muslims have called him Hujjat al-Islam, the Proof of Islam, for nine centuries. He belongs on a Christian apologetics site for a plain reason: the argument most often heard today for a Creator is his. Whatever begins to exist has a cause; the universe began to exist; therefore the universe has a cause. Christian philosophers call that the kalam cosmological argument, after kalam, the Arabic word for the discipline of Muslim theology (it means "speech" or "discourse," and came to mean reasoned argument about God). Al-Ghazali did not invent every part of it, and the Christian John Philoponus and the Muslim al-Kindi had argued for a beginning before him, but he gave the argument the compact form that carried, and the modern Christian version is a direct descendant. One fact worth carrying away: the Latin West met him first as a name on a book jacket, "Algazel," and got him almost exactly backwards. The book that reached Paris was his summary of the philosophers’ positions, translated without the preface explaining that he was summarizing them in order to demolish them. For more than a century, Christian scholars cited the man who wrote The Incoherence of the Philosophers as though he were one of the philosophers. His birth year is a convention rather than a certainty. The medieval biographers give 450 AH, and AH counts the years of the Muslim calendar from the hijra, Muhammad’s move from Mecca to Medina in 622, so 450 AH falls in 1058. That is the date the tradition settled on. Several modern scholars, reading a remark in his own autobiography, argue for 1055 or 1056 instead, and there is no document that decides between them. So every age counted from his birth carries the same uncertainty, and the round numbers are worth holding loosely.

(●) c. 1058 AD: Born at Tus in eastern Persia, and orphaned young. + Tus sat in Khorasan, the north-eastern province of the Persian world, near what is now Mashhad in Iran. It was a provincial town in a vast empire: the Seljuq Turks ruled the territory, the Abbasid caliph in Baghdad held the religious title, and the roads between them carried scholars looking for a patron. The traditional account of his childhood comes from biographers writing generations later, so it is a story the Muslim world has always told rather than a documented fact. His father, it says, was a poor spinner of wool who loved the company of scholars and prayed for learned sons. When he died he left Muhammad and his younger brother Ahmad to a Sufi friend, a man of the Muslim mystical tradition that sought God by stripping away everything else, along with a small sum for their education. The money ran out, as small sums do, and the friend put the boys into a madrasa, a residential college where students were fed and housed. Later in life al-Ghazali is said to have remarked that he had begun studying for the sake of something other than God, and that the studies had refused to be for anything else. Even his name is a small puzzle. Some read it al-Ghazzali, from ghazzal, a spinner of wool, which fits the story about his father; others read al-Ghazali, from Ghazala, a village near Tus. Both spellings are old, and the medieval sources do not settle it.

(●) 1085 AD: His teacher at Nishapur died, and the best student in Persia went looking for a patron. + As a young man he made his way to Nishapur, then one of the great cities of the eastern Islamic world, to study under al-Juwayni, known as Imam al-Haramayn, the Imam of the Two Holy Cities. Al-Juwayni was the leading theologian of the Ash’arite school, the tradition of Sunni theology that had grown up defending revealed doctrine with the tools of rational argument. Under him al-Ghazali learned law, logic, and disputation, and learned them so quickly that his teacher is supposed to have said of him, with more exasperation than warmth, that he was a deep ocean who would drown you. Then, in 1085, al-Juwayni died. Learning in that world followed the teacher rather than the building, so when he died the circle around him scattered, and a young scholar with no master and no post had to find someone willing to keep him. Al-Ghazali went to the military camp of Nizam al-Mulk, the Seljuq vizier who effectively ran the empire and who had built a chain of state colleges, the Nizamiyya madrasas, to train the men who would staff its courts and mosques. The camp was a moving university as much as an army headquarters: scholars debated in front of the vizier, and reputations were made in an afternoon. Al-Ghazali made his there.

(●) 1091 AD: At thirty-three he was given the most coveted chair in Islam. + Nizam al-Mulk appointed him to the Nizamiyya of Baghdad, the flagship college of the empire, in the capital of the caliph, the Abbasid successor of the Prophet who was the titular head of Sunni Islam while the Seljuq sultan did the actual ruling. Three hundred students are said to have crowded his lectures, and they were not ordinary students: they were the coming judges and jurists of the Islamic world. He was consulted by the court. At the caliph’s request he wrote against the Isma’ilis, a Shi’ite movement teaching that the Qur’an carries a hidden meaning reachable only through an infallible teacher, and one whose followers in Persia by then held mountain fortresses and had begun murdering officials who opposed them. By any measure his society could apply, he was at the top. He was also, by his own later account, miserable about why he was there. Looking back, he wrote that the fairest-seeming of all his activities was his teaching, and that when he examined its motives he found it "only actuated by a vain desire of honour and reputation." A man can be entirely right about his subject and entirely wrong about himself, and he came to think that was his exact condition. The empire around him was a good deal less secure than his lecture hall. In 1092 Nizam al-Mulk, the patron who had made him, was assassinated, and the killing was laid at the door of the Isma’ilis. The sultan Malikshah died weeks later, and the succession dissolved into fighting. So the doctrine al-Ghazali was refuting on paper had men in the street with knives, and the two men who had guaranteed his position were both gone inside a single autumn.

(●) 1095 AD: He spent two years learning the philosophers’ system, and then wrote The Incoherence of the Philosophers against it. + The philosophers he had in view were the falasifa, the Muslim thinkers who had taken up Aristotle and the later Greeks and built a system out of them. The greatest was Avicenna, dead nearly sixty years, whose account of God as the Necessary Existent had reshaped how educated Muslims thought about creation. The Necessary Existent is the one being whose non-existence is impossible, the being that has to be there whatever else is or is not, and on Avicenna’s account everything else pours out of it the way conclusions pour out of a premise. It is a magnificent picture. On several points it was also flatly at odds with the Qur’an: the world had no beginning, God knew only universal truths and not the individual man in front of him, and what survived death was the soul alone and never the body. Al-Ghazali did something unusual before attacking. He taught himself the whole system, in his spare hours, over roughly two years, and then wrote it out fairly in a book called The Aims of the Philosophers, a summary so clean that a reader could use it as a textbook. Only then did he write the attack, The Incoherence of the Philosophers, finished in January 1095. Its method is what makes it formidable. He does not appeal to the Qur’an against them. He takes twenty of their claims and argues, on their own logical ground, that they have not proved what they said they proved. The Andalusian philosopher Averroes answered it a lifetime later with a book titled The Incoherence of the Incoherence, which tells you how hard the first book had landed.

(●) 1095 AD: His voice failed in the lecture hall, and he walked out of his own life. + By his own account the crisis had been building for about six months. He would resolve in the morning to leave Baghdad and by evening talk himself out of it, pulled one way by what he called the voice of religion and the other by the fear of losing a position that no one gives up. Then the argument settled itself in his body. "God caused an impediment to chain my tongue and prevented me from lecturing," he wrote. "Vainly I desired, in the interest of my pupils, to go on with my teaching, but my mouth became dumb." He stopped eating, and grew weak enough that the physicians gave up. Their diagnosis, as he reports it, is the sentence that turns the story: "The mischief is in the heart, and has communicated itself to the whole organism; there is no hope unless the cause of his grievous sadness be arrested." In November 1095 he left. He announced publicly that he was going on pilgrimage to Mecca, because a professor who says he is going to Syria to live as a poor man invites the authorities to stop him, and he admits in the autobiography that the announcement was a cover. He settled money on his children, gave away the rest, installed his brother in the lectureship, and rode out of Baghdad.

(●) 1095 to 1106 AD: Eleven years of Damascus, Jerusalem and Mecca, spent unlearning the man he had been. + He went to Syria first, and by his own account spent about two years there. He describes shutting himself into the minaret of the great mosque at Damascus and spending his days there with the door closed behind him. From there he went to Jerusalem in 1096, three years before the crusading armies took it, and shut himself daily inside the Dome of the Rock. Then Hebron, to the tomb the region calls the shrine of the Friend of God, meaning Abraham, where he vowed never again to serve a ruler or teach in a state college. Then the pilgrimage itself, to Mecca and Medina. Eventually the road ran out and he went home to Tus, where he set up a small school and a Sufi lodge, a house where men lived under a rule of prayer and discipline, and taught a handful of disciples. He is honest that the retreat was never as clean as he wanted: "events, family cares, and vicissitudes of life changed my resolutions and troubled my meditative calm." Out of these years came the Ihya’ ‘ulum al-din, The Revival of the Religious Sciences, forty books in four parts, and the largest thing he ever wrote. It is a strange and impressive object: a complete manual of Muslim life that begins with ritual washing and the etiquette of eating and ends with the diseases of the heart, envy, pride, love of status, and the love of God. Muslims have quoted a saying about it ever since, that if every other Islamic book were lost and only the Ihya’ remained, it would make up for them.

(●) 1106 to 1111 AD: He went back to the lectern, told the whole story in a short book, and died at Tus. + In 1106 Fakhr al-Mulk, the son of the vizier who had first promoted him, pressed him to return to teaching at the Nizamiyya of Nishapur. He went, and he was uneasy about going, since at Hebron he had more or less vowed not to. His defence had two parts. A new century was about to turn on the Muslim calendar, and a saying long current among Muslims promised that God raises up at the head of every hundred years a renewer, a man sent to scrub the rust off the faith of his generation. And a lectureship, he decided, is not the same sin twice: if he could teach now as a man seeking God rather than as a man seeking a reputation, the return was not a relapse. Around this time he wrote al-Munqidh min al-dalal, Deliverance from Error, answering a friend who had asked him to explain himself. It is short, personal, and disarming, and it is the reason we know any of this. He tells about the doubt that took him to the point of trusting nothing but sense and mathematics, about the two years with the philosophers, about the paralysis of his tongue, and about why he came back. Western readers have compared it to Augustine’s Confessions since the nineteenth century, and the comparison holds for the shape of the book more than for its theology. He retired again to Tus and died there on 18 December 1111. A late tradition, told by his brother Ahmad, has him rise at dawn, call for his shroud, kiss it, lay it over his eyes and say that he hears and obeys the order to enter the King’s presence. He was in his early to middle fifties.

What He Taught

(T1) Whatever begins to exist has a cause, and the world began to exist. + Think about what you do when a friend tells you her car started making a noise last Tuesday. You do not ask whether something caused it. You ask what. The noise was not there and then it was, and a thing that starts is a thing that something started. Al-Ghazali’s argument for God is that sentence taken seriously and applied to everything at once. If the whole world began, then the whole world is like the noise, and behind it there has to be something that did not begin. Notice how modest the first premise is. It does not say that everything has a cause, which would invite the obvious retort, "then what caused God?" It says that whatever begins has a cause, and a God who never began is not covered by it. The weight therefore falls on the second premise, that the world began, and this is where he did his hardest work. The philosophers held that the world is eternal, running back forever without a first moment. Against them he argued that an infinite series of past events cannot actually have been completed, and he made the point with a piece of their own astronomy. Suppose the sphere of the sun completes one revolution a year and the sphere of Saturn one revolution in thirty years. If the past is infinite, both have completed an infinite number of revolutions, and the numbers must be equal, since infinity is infinity. Yet one of them has run thirty times as often as the other. Something has gone wrong, and what has gone wrong, he says, is the supposition that an infinite number of past revolutions was ever actually completed. You may want to answer that infinity simply does not behave like ordinary counting, and that the two spheres can both have run infinitely often without either total being larger. That reply is not a modern invention, and the argument between it and al-Ghazali is still going on nine hundred years later, which is a fair sign of how good the objection is and how good his question was. He then presses a second question, the one the philosophers thought was fatal to any doctrine of creation. If God is unchanging, why did he make the world at one moment rather than another? Al-Ghazali’s answer is that God is not a mechanism but an agent with a will, and an agent can choose one moment rather than another for no reason beyond the choosing, the way a man with two equal dates in front of him, unable to take both at once, takes one of them even though nothing in the dates decides which. That answer is the heart of his disagreement with Avicenna, and it is why the argument leads to a personal Creator rather than to an impersonal first principle.

(Q) "Every being which begins has a cause for its beginning; now the world is a being which begins; therefore, it possesses a cause for its beginning." + Source: al-Ghazali, Kitab al-Iqtisad fi’l-i’tiqad (The Moderation in Belief), first treatise, opening proposition, in the English rendering William Lane Craig gives in The Kalam Cosmological Argument (1979), made from S. de Beaurecueil’s French translation of the Arabic. Aladdin M. Yaqub’s full English version (University of Chicago Press, 2013) carries the same argument in the same place. Three lines, and the whole argument is on the table. Al-Ghazali sets it out at the opening of his own systematic theology, written not long after the attack on the philosophers, and then spends the following pages defending the second line, which is the one that costs something (T1).

(T2) Fire touching cotton is not the reason the cotton burns. + Here is the question he is really asking. Strike a match, hold it to a scrap of cotton, and the cotton blackens and burns. You have seen it a hundred times, and you would say the fire burned it. But what did you actually see? You saw the fire arrive, and you saw the burning, one after the other. You never saw the making-it-burn. That part you supplied. Al-Ghazali’s point is that a constant pairing is not the same thing as a necessary connection, and that all our confidence in nature rests on the pairing. Fire, he says, is an inanimate thing; it does nothing, and cannot be shown to be an agent at all. What we call the laws of nature is God’s settled habit of producing the second thing whenever the first thing appears, reliable because he is reliable and not because the cotton has no alternative. The position has a name, occasionalism: the view that created things are the occasions on which God acts rather than genuine causes in their own right. It has an obvious payoff. If burning is God’s doing and not the fire’s, then a fire that does not burn Abraham, or a sea that opens, is not a violation of anything. It is simply God doing on one occasion what he does not usually do. He is more careful than he is often given credit for. In the same discussion he offers a second, weaker position for anyone unwilling to give up natures altogether: grant that fire does burn by its nature, and hold instead that the prophets’ miracles run through causes we have not identified. He explicitly leaves both routes open, which means that reading him as a simple destroyer of natural causation goes past his own words. Christian theology has generally taken a third road, secondary causation, on which God gives creatures real powers of their own and upholds them in acting, so that the fire genuinely burns and God is genuinely the first cause of its burning. But the question al-Ghazali forced, whether observed regularity by itself proves necessity, is a live one, and David Hume was still asking it in Edinburgh six and a half centuries later.

(Q) "In our view, the connection between what are believed to be the cause and the effect is not necessary." + Source: al-Ghazali, Tahafut al-Falasifa (The Incoherence of the Philosophers), Seventeenth Discussion (Kamali translation). The opening sentence of the discussion the book is most famous for. He goes on to list the pairs everybody treats as fixed, drinking and the quenching of thirst, eating and the satisfying of hunger, contact with fire and burning, and to argue that in each case the two are joined by God’s decree rather than by any necessity in the things themselves (T2).

(T3) On three questions the philosophers had left the faith, and on the rest they were merely mistaken. + Twenty charges are laid in The Incoherence, and at the end he sorts them. On seventeen of the twenty he declines to press the charge of unbelief, since on those the philosophers are saying what Muslim groups such as the Mu’tazilites had already said. The Mu’tazilites were an older school of Muslim theologians, going back to the eighth century, who gave reason the first word in matters of doctrine, and who had been arguing points of that kind inside the community for three hundred years and more, answered as Muslims in error rather than shut out as unbelievers. That is the standard he is applying: a position other Muslims already hold, and argue about, is a mistake to be corrected rather than a door out of the faith. Three of the twenty are different, and he names them: that the world has always existed, that God knows only general truths and not particular things and people, and that the dead are not raised bodily. Look at what those three have in common. Each of them, if true, would cancel something a believer has to be able to say. A world that never began needs no maker. A God who knows humanity in general but not the particular woman praying tonight cannot be prayed to. A resurrection of souls without bodies is not the promise that was made. Al-Ghazali is not condemning the philosophers for using Aristotle. He is saying that on these three points their conclusions and their religion cannot both be held. The judgment he attached to those three, takfir, the declaration that someone has left Islam, was a serious legal act, and he wrote a whole treatise later, The Decisive Criterion, restraining its use and warning against the habit of throwing the charge at every opponent. His own rule there is that a man is not to be declared an unbeliever for a disagreement in interpretation, only for calling the Prophet a liar. The three points also mark where Christians can watch a fellow monotheist defending ground they hold too. Creation with a beginning, a God who numbers hairs and sparrows, and the raising of the body are Christian convictions before they are anything else, and it is worth noticing that a Muslim theologian in Baghdad identified the same three as the load-bearing walls.

(Q) "To brand the philosophers with infidelity is inevitable, so far as three problems are concerned: namely (i) the problem of the eternity of the world, where they maintained that all the substances are eternal. (ii) their assertion that Divine knowledge does not encompass individual objects. (iii) their denial of the resurrection of bodies." + Source: al-Ghazali, Tahafut al-Falasifa (The Incoherence of the Philosophers), conclusion (Kamali translation). The verdict at the very end of the book, after twenty discussions of argument. He adds at once that on the remaining questions the philosophers say nothing the Mu’tazilites had not already said, and that whether a Muslim innovator is to be counted a heretic is a question he will not settle there (T3).

(T4) A faith defended by denying arithmetic will fall when the arithmetic holds. + He divides what the philosophers do into six fields: mathematics, logic, physics, metaphysics, politics, and ethics. Then he says something that a modern reader may not expect from the man who wrote a book called The Incoherence of the Philosophers. Mathematics has nothing to do with religion at all, and its proofs, once understood, cannot be refuted. Logic likewise contains nothing for or against faith; it is simply the study of what follows from what, and he liked it well enough to write three books of his own on it and to work its rules into his own theology. His warning runs in both directions, and both directions still bite. The first danger is that a young man dazzled by the exactness of geometry will assume the same exactness in everything else the geometers say, and follow them into metaphysics where their arguments are guesswork. That is a mistake about the reach of expertise, and it is the same mistake as taking a brilliant physicist’s opinion about God to be a physicist’s opinion. The second danger is the pious one, and he treats it as the worse of the two. A well-meaning believer who thinks he is defending the faith by rejecting the astronomers’ account of eclipses does not damage astronomy. He damages faith, because the philosopher who knows the eclipse calculations are sound now believes that religion rests on ignorance, and his contempt for religion grows in proportion to his confidence in his tables. Al-Ghazali is blunt that the calculation of the orbits, conjunctions, and oppositions of the sun and moon contradicts nothing the Prophet said. Nine centuries later, the argument has not aged: a Christian who stakes the resurrection on the age of the earth has not protected the resurrection, he has lent it a hostage.

(Q) "It is therefore a great injury to religion to suppose that the defence of Islam involves the condemnation of the exact sciences." + Source: al-Ghazali, al-Munqidh min al-dalal (Deliverance from Error), on the philosophical sciences (Claud Field translation, 1909). He has just described the believer who condemns the theory of eclipses in the name of religion, and the philosopher who hears him and concludes that religion is built on ignorance. The next sentences insist that the religious law neither approves nor condemns the exact sciences, and that they in turn make no attack on religion (T4).

(T5) The knowledge that changes a man is tasted, not merely proved. + This is the point of the breakdown, and he explains it with an illustration anybody can check. A physician can define drunkenness precisely. He can tell you what causes it, what it does to judgment, how long it lasts. The drunk man can define nothing; he is in no condition to define anything. Yet only one of the two knows what being drunk is like, and it is not the physician. Or take the doctor who falls ill: he has a theoretical knowledge of the health he no longer has. Al-Ghazali applies the distinction to himself with some brutality. He had proofs. He could argue the existence of God against any philosopher in Baghdad and win. What he found, when he examined his own motives, was that the proofs had not touched the thing they were about, and that the argument he could not win was with his own appetite for status. What was missing, he concluded, was not another demonstration. It was a change in the man doing the demonstrating. So he went to the Sufis, the Muslim mystics whose discipline aimed at emptying the heart of everything that was not God, and he went as a practitioner rather than a reader, because he had already read them and found that reading was not the thing. The Arabic word he uses for the knowledge he was after is dhawq, "taste": the difference between being told that honey is sweet and having some. Christians will recognize the distinction and should also notice the difference in where it lands. Scripture also insists that knowing about God is not yet knowing God, and Jesus makes purity of heart the condition of seeing God (Matthew 5:8). But the road al-Ghazali travels is one of ascent by discipline, a purifying of the self that the seeker performs. The gospel road runs the other way: the heart is not merely untrained but "deceitful above all things, and desperately sick" (Jeremiah 17:9), and what changes it is God’s action, not the seeker’s technique (Titus 3:5).

(Q) "I saw that Sufism consists in experiences rather than in definitions, and that what I was lacking belonged to the domain, not of instruction, but of ecstasy and initiation." + Source: al-Ghazali, al-Munqidh min al-dalal (Deliverance from Error), on Sufism (Claud Field translation, 1909). The sentence comes immediately after the comparison of the physician and the drunk man. Field renders as "ecstasy" the Arabic dhawq, tasting, the direct experience the Sufis contrasted with book learning (T5).

(Q) "Knowledge of self is the key to the knowledge of God, according to the saying: ‘He who knows himself knows God.’" + Source: al-Ghazali, Kimiya-yi sa’adat (The Alchemy of Happiness), chapter one (Claud Field translation, 1910). The opening line of the Persian book he wrote to put the substance of the Ihya’ within reach of ordinary readers. The saying he quotes is a maxim the Sufis attributed to the Prophet. Christian readers have heard the same note in Augustine, who prayed to know himself in order to know God, and in Calvin, whose Institutes open by saying that knowledge of God and knowledge of ourselves are joined together.

What Christian Thinkers Made of Him

(†) The Latin West met him as "Algazel" and filed the prosecutor with the accused. + In twelfth-century Toledo, a city recently taken from Muslim rule and full of Arabic manuscripts, a stream of translations began crossing into Latin. Among them was al-Ghazali’s Aims of the Philosophers, put into Latin by Dominicus Gundissalinus working with a collaborator the manuscripts call Magister Iohannes. It circulated under the title Summa theoricae philosophiae, and its author became "Algazel." There was one problem, and it lasted for centuries. The Arabic book opens with a preface explaining that what follows is a fair statement of the philosophers’ views, set out so that they can be refuted in a companion volume. The Latin version that circulated left the preface out. Latin readers therefore had, under the name Algazel, an admirably clear textbook of Avicennian philosophy with no hint that its author thought the whole thing false on the points that mattered. Thomas Aquinas cites Algazel as one of the Arabic philosophers. Ramon Llull wrote a compendium of Algazel’s logic in verse. The irony is worth sitting with, because it is a lesson about how ideas travel. The most effective critic Aristotelian philosophy had in the medieval world spent more than a century in Christian libraries as one of its ablest exponents, and the misunderstanding turned on a missing page.

(†) A Dominican in Barcelona found the real books and put them to work. + Ramon Marti, a Catalan Dominican of the thirteenth century, learned Arabic in order to argue with Muslims and Jews in their own sources, and he read what the translators had skipped. In his Pugio fidei, the Dagger of Faith, and in his other works he quotes al-Ghazali at length from Deliverance from Error and from The Incoherence of the Philosophers, which he renders into Latin himself and calls the Book of the Ruin of the Philosophers. Some of those passages are their first appearance in any European language. What Marti wanted from him was the case against the eternity of the world and against a God who does not know particulars, made by a Muslim, which meant it could not be waved away as Christian special pleading. He filled the opening book of the Pugio with chapters drawn from Aquinas’s Summa contra gentiles and with long passages of Arabic philosophy he had turned into Latin himself. He was not quite the only one who noticed, either. Roger Bacon, writing at Oxford in the same century, records in his Communium naturalium that the Aims had a preface and that a book against the philosophers existed. Al-Ghazali had made his case on strictly rational ground, refusing to quote Scripture at the philosophers. That is exactly what made him portable. An argument built without appeal to the Qur’an can be picked up by a Christian without dismantling.

(†) The argument he sharpened is the one Christian philosophers defend today under the name kalam. + For most of the modern period his cosmological argument was a historical curiosity in the West. Then in 1979 the Christian philosopher William Lane Craig published The Kalam Cosmological Argument, took al-Ghazali’s three-line syllogism as his starting point, named the argument after the Muslim theological tradition it came from, and made it the most discussed argument for God’s existence of the following forty years. What changed in the meantime is the second premise. Al-Ghazali had to defend the claim that the world began entirely by philosophical reasoning, and the philosophers of his day thought he had lost. In 1929 Edwin Hubble showed that distant galaxies are receding, and the physics that followed described a universe with a finite past. A premise that had been argued in a Baghdad lecture hall now had observational support from astronomers, most of whom had never heard of the man who framed it. Craig’s form is al-Ghazali’s, almost word for word: whatever begins to exist has a cause; the universe began to exist; therefore the universe has a cause. He also revived al-Ghazali’s two supporting arguments, that an actually infinite number of things leads to contradictions and that an infinite series cannot be completed by adding one member at a time, and he credits al-Ghazali by name for both. So does the objector: when a critic takes on the hotel with infinitely many rooms, or presses the question why the Creator acted at one moment rather than another, the argument being answered is a Muslim theologian’s from 1095.

(†) Where the gospel parts company with him: the Son, the cross, and a God whose goodness is his nature. + He was a Muslim, and a serious one, and the disagreements are real. Four of them matter most. - The Trinity and the Incarnation. Al-Ghazali held tawhid, the absolute oneness of God, in the form that excludes any partner, any son, and any divine person other than God himself. On his account Christians had taken a prophet and made a god of him. The gospel says the opposite happened: God took a nature and made himself a man. "And the Word became flesh and dwelt among us, and we have seen his glory, glory as of the only Son from the Father, full of grace and truth." (John 1:14) - The cross. With the Qur’an he denied that Jesus was crucified, and with the crucifixion goes the atonement. What is lost is not one event but the answer to the question al-Ghazali spent eleven years on, how a defiled heart is cleansed. Scripture answers by pointing away from the seeker entirely: "In this is love, not that we have loved God but that he loved us and sent his Son to be the propitiation for our sins." (1 John 4:10) Propitiation means the sacrifice that turns aside a just anger, and Christian preaching has always known this is the offensive part (1 Corinthians 1:23). - The purified heart and the gift. The Ihya’ is a ladder: purify, discipline, empty the heart, and God may be tasted at the top. It contains real wisdom about self-deception, and Christians can learn from its diagnosis while rejecting its cure. The gospel begins where the ladder ends: "For by grace you have been saved through faith. And this is not your own doing; it is the gift of God, not a result of works, so that no one may boast." (Ephesians 2:8–9) - Whether God has a nature. This is the deepest of the four and the least noticed. In the Ash’arite theology al-Ghazali defended, nothing is obligatory upon God and nothing is good or evil in itself; a thing is good because God commands it, and he could have commanded otherwise. The same instinct drives the account of causation (T2), where fire has no power of its own and God’s will is the only agent in the room. Christian theology says something different: God is good in his own being, not merely in his decrees, and there are things he cannot do because of who he is. "if we are faithless, he remains faithful—for he cannot deny himself." (2 Timothy 2:13) A God who could have made cruelty a virtue is not the God who is love. None of this makes him a lesser thinker, and it is worth saying what the ledger also shows. He was a monotheist arguing that the universe had a beginning and a Maker, that God knows each person by name, that the body will be raised, and that a heart can be so full of ambition that its owner cannot see it. On every one of those, a Christian stands beside him. The parting comes at the point where he says the way up is a discipline and the gospel says the way up came down.