Islamic Studies al-Ghazali
Oliver Leaman
  • LAST REVIEWED: 10 May 2017
  • LAST MODIFIED: 26 May 2016
  • DOI: 10.1093/obo/9780195390155-0028


Al-Ghazali (c. 1058–1111) is widely regarded as one of the most impressive thinkers in the Sunni Islamic world, encompassing a wide range of intellectual positions through his career. He started off as a fairly standard Ashʿarite theologian but then became interested in philosophy in the Peripatetic tradition, which he sought to refute, yet he also held onto some of its main principles and arguments. In his position as a major thinker in the Sunni state based in Baghdad, he also spent some time and effort refuting the Ismaʿili challenge to orthodox Islam. Finally, he became entranced with a version of Sufism and abandoned his official role and public status, preferring the relative solitude and isolation of the mystical form of life. In all his writings, al-Ghazali put his own character into his work, and it is never possible to accuse him of following others’ ideas slavishly. Indeed, if there is one theme that al-Ghazali can be said to have maintained throughout his life, it is his repugnance for taqlid (imitation) and his advocacy of the significance of discovering the truth for oneself. Given his frequent change of view, he was often accused by his enemies of being inconsistent, and the precise nature of his thought is difficult to pin down definitively, thus leading to extensive controversy between those who believe that he is basically a philosopher with an interest in mysticism and those who regard him predominantly as a mystic with occasional philosophical ways of expressing himself.


A very comprehensive listing of new translations, critical works, and articles on the thinker appear in Daiber 1999 and Daiber 2007. The al-Ghazali website has some less familiar material in non-English languages but is far less comprehensive. A very useful set of references may be found in Griffel 2007, an entry in the Stanford Encyclopedia of Philosophy.


Abu Hamid Muhamad al-Ghazali was born in 1058 or 450/1059 in Tus and was educated there with his slightly younger brother Ahmad, who also went on to become a distinguished thinker. Al-Ghazali came to work with al-Juwayni, the Ashʿarite theologian, at the Nizamiyya college in Nishapur, and Watt 1963 explains how he grew close to the court, being appointed to an official teaching official position at the Nizamiyya college in Baghdad in 1091. Al-Ghazali 2004 describes his life and how in 1095 he underwent a spiritual crisis and left his post, traveling around the Islamic world until he ended up in his hometown of Tus, where he taught in a small private college until he took up a post at the Nizamiyya college in Nishapur in 1106. He seems to have justified this decision to return to public life because the parlous nature of the times demanded a change in his attitude toward such an official role. He died in 505/1111. Campanini 1996, Griffel 2009, Lazarus-Yafeh 1975, and Nakamura 1998 find in his life important information about his intellectual career. Al-Ghazali’s works on philosophy were very popular in the Jewish world and became much studied by Jews. He was also translated into Latin as “Algazel,” and much quoted, although in both contexts he tended to be regarded as just another philosopher, not a critic of philosophy. In Islamic philosophy he continues to be discussed in the early 21st century, and he was extensively studied in the past. The personal nature of his style is linked with the content of his thought, and the passion with which he develops his arguments, along with their rigor, has contributed to his continuing role in Islamic culture. Mitha 2001 provides a balanced account of his complex attitudes toward the Ismaʿilis Treiger 2012 discusses how his various books represent stages in the development of his thought and how he reacted to the works of others at different times. On the other hand, Garden 2014 argues for the significance of his theological ambitions for the whole of his intellectual output.

The Attack on Philosophy

Al-Ghazali concentrated on a number of views, three of which, he argued, are not only erroneous but also heretical (see al-Ghazali 1997). The eternity of the world is one of these, and the philosophers of the time tended to argue that the world eternally emanates from God, as opposed to having been created at a point in time out of nothing. Al-Ghazali argued that if God really did make the decision to create the world, it did not just flow from his existence but must at some stage not have existed, and then with his decision it came into existence. It is only meaningful to call God an agent if he is capable of willing something to happen, and the philosophical account of creation makes it look very much like an inevitable process in which God merely participates, and that he does not determine. Al-Ghazali also rejected the arguments that God cannot know anything about contingent particulars, and that the afterlife is only spiritual. Hourani 1958 shows that al-Ghazali argued that these theses are not only false theologically, they are also invalid logically, and so tried to cut at the essence of the philosophical approach. It was formerly thought that the Incoherence of the Philosophers (sometimes translated as the Refutation of the Philosophers) was a general attack on philosophy, but some observers, such as Jules Janssens (see Janssens 2003), now argue that al-Ghazali is, in fact, closer to philosophy than is generally appreciated, and that this text and some of his other putative critical works on philosophy are more the views of one philosopher toward others than a radical critique of philosophy itself. Al-Ghazali set his sights, in particular, on some of the views of Ibn Sina or Avicenna (see Avicenna 2005), and yet at the same time he was attracted to other aspects of Ibn Sina’s thought, which recur time and again in his work. In particular, he was enthusiastic about logic itself as a methodology, and with reason as a whole. Like Ibn Rushd, who set out to directly challenge al-Ghazali’s Refutation of the Philosophers with his Refutation of the Refutation (Ibn Ibn Rushd 1954), al-Ghazali believed that when a scriptural passage is not in line with reason, then it requires a symbolic or allegorical interpretation, which is certainly to elevate reason to a high status in Islamic thought. It is almost as though al-Ghazali accepted the central defense of philosophy initiated by al-Farabi that logic represents the deep structure of thought, but at the same time rejected much of the Neoplatonic philosophy that al-Farabi and his successors constructed on that base. The modal implications of this view are brought out by Kukkonen 2000. Leaman 1997 suggests that al-Ghazali, like Ibn Rushd, was critical of much theology, agreeing with the later thinker that if theologians would only use respectable logical techniques to resolve the issues they regard as outstanding, they would soon establish a resolution of their protracted arguments. This is also a point he made against the Ismaʿilis, who criticized the idea of basing interpretation of scripture on ijma, given the difficulties in establishing consensus. According to al-Ghazali, consensus, in principle, is not difficult to establish; it is just that those working in theology are frequently not well advanced enough logically to see how to resolve controversial issues. The implications of this doctrine for the soul are outlined in Gianotti 2001.

Al-Ghazali the Theologian

Marmura 2005 outlines how al-Ghazali spent much of his life defending the Shafiʿi school of jurisprudence and the Sunni form of Islam, and has generally been assumed to be a member of the Ashʿarite theological school. In his technical theological texts, he tends to favor the Ashʿarite position in most areas of theology, but his major text on theology is a work that he obviously regarded as his major contribution, The Revival of the Religious Sciences (Ihyâ’ ‘ulûm al-dîn), a rather gloomy forty-volume series of works centered on the possibility of redemption and what gets in its way, represented here in translation by al-Ghazali 1989, al-Ghazali 1997, and al-Ghazali 2001. What is remarkable about this work, apart from its size, is its almost total exclusion of arguments. It is really an account of the sorts of behavior we ought to cultivate with our own salvation in mind, with the emphasis on achieving pure states of mind, clearly a result of al-Ghazali’s latter-day commitment to Sufism, as outlined in Shehadi 1964. He takes a rather pietistic approach here, favoring asceticism and the acquiring of appropriate virtuous forms of behavior as a result of self-discipline. What makes reason singularly inappropriate here is its inability to judge what is right and wrong. According to Hourani 1976 and Hourani 1985, al-Ghazali believed that people desperately need the help of scripture, for otherwise they have no idea how to behave; what leads to paradise is good, and what leads to hell is bad, so there is nothing in the actions by themselves that inevitably can lead one to classify them in a particular way. Leaman 2009 defends al-Ghazali’s approach to ethics, suggesting that it is not as opposed to rationalism as is often suggested by the commentators.


According to al-Ghazali, God created the universe as a vast mechanism, and everything about it is designed by him and kept in existence by him. In fact, the connections between everything in the universe can be understood causally, and once God establishes the connections between things, they have to take place as he wishes. Frank 1992 and Frank 1994 point out that this view is also found in the thought of Ibn Sina. Ormsby 1984 shows that this world is also taken to be the best of all possible worlds, a view that later may be found in Ibn Rushd as well—though Dutton 2001 analyzes their differences on this issue. It is in the area of causality that much modern controversy exists. The accepted view formerly was that al-Ghazali, as an Ashʿarite, was an occasionalist, in the sense that he believed that what is regarded as causality is merely an impression of regularity in nature resulting from what God brings about on our behalf. God kindly organizes the world in a way that makes events regular and comprehensible, but in themselves there is nothing that holds those events together except for the power and will of God. By contrast, Ibn Sina tends to regard causal connections as necessary, and once God has set the whole natural process into operation, it runs automatically and according to a plan determined by the nature of things and their interconnections. Al-Ghazali certainly did not accept this; for him, if God is to be a real agent, he must have the power to change his mind at any time, and he must control how things link up with each other, if they do at all. The debate is summarized in Leaman 1996, which suggests that those arguing for and against al-Ghazali’s Ashʿarite credentials often emphasize different aspects of his thought. But Marmura 1981 and Marmura 1995 show that al-Ghazali accepted that causality exists, but he argued that its basis is God and not anything independent of God. He also argued, in vindication of this view, that we could understand a situation in which things behave very differently from how they normally behave, which shows that causality cannot be part of the meaning of things.

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