For centuries, Muslim thinkers focused on God's Word. Then foreign ideas began creeping in like occupying troops. Starting in the ninth century, Muslims translated Greek texts into Arabic—works by Aristotle and other philosophers brought new ways of thinking.

The Qurʾān encourages believers to think and reflect: "Will they not understand?" and "Do they not consider?" But problems arose when reason seemed to contradict revelation.

Aristotle taught that God is perfect, which Muslims agreed with. But he also said perfect beings must be simple. This created problems: if God has qualities like being living, mighty, and all-knowing—as the Qurʾān says—wouldn't that make Him complex?

Worse, Greek reasoning said a perfect God couldn't know temporary things because His knowledge would have to change, making Him imperfect. But the Qurʾān says, "Not a leaf falls but that He knows it."

Different Muslim scholars tried to solve this. Philosophers like Ibn Sīnā and Ibn Rushd had one approach. Theologians like al-Ghazālī and al-Rāzī had another. Ibn Taymiyya offered a third perspective.

The main debate was when to interpret Qurʾānic verses figuratively instead of literally when reason objected to the plain meaning. By al-Rāzī's time in the twelfth century, scholars created a "universal rule": when reason and revelation conflict, reason wins, and religious texts should be reinterpreted accordingly.

This rule marked a turning point in Islamic thought.

The Qurʾān and Knowledge

The Qurʾān is a book intensely concerned with knowledge. It addresses believers to reflect—especially to reflect upon the created order, including man, as a sign of God and it boldly challenges its readers to find within it any fundamental contradiction (Q 4:82) and to inspect the created order with careful scrutiny for any gaps (Q 67:3-4).

It is a remarkable fact that nowhere in the Qurʾān is knowledge (ʿilm) contrasted with faith (īmān), as is typical in modern parlance, but only with lack of knowledge, or ignorance (jahl, jahāla). Knowledge and faith, rather, are presented as being fully concomitant and mutually entailing. At the same time, the Qurʾān squarely admits that human reason, being a faculty of a limited and finite being, is of necessity not boundless (Q 17:85).

In its insistence on the centrality of knowledge and its persistent encouragement to reflect, the Qurʾān also describes itself variously as an "evincive proof" (burhān) (Q 4:174) a "criterion of judgement" (furqān) (Q 2:185), an "elucidation" (bayān) (Q 3:138), a "clarification of all things" (tibyānan li-kulli shayʾ) (Q 16:89), and as "consummate wisdom" (ḥikma bāligha) (Q 54:5).

This description is in fact of key importance because it establishes, or at least opens the door to, a complementary and harmonious pondering over the relationship between reason and revelation in Qurʾān.

The Prophet was naturally questioned by his Companions on numerous occasions regarding matters of the hereafter, God, angels, and a host of other topics directly connected to the creedal content of the new faith. The Prophet warned the community against the inherent futility of pursuing certain lines of rational inquiry, "Satan shall come to you and say, 'Who created this?' and 'Who created that?' until he says, 'Who created your Lord?' So if anyone of you should reach this point, let him seek refuge in Allah and desist." (Bukhari 807)

Thus rationality in Islam is sometimes used and sometimes even contraindicated.

The Qurʾān was and is accepted by all Muslims as the final revelation of Allah. Yet the difference in its understanding is an opinion varied amongst Muslims. There were three trends amongst Muslims about Fiqh (Laws of Islam), one opted for pure traditionalist viewpoint represented by Hanbali Zahiri school of thought - while other people gave preference to personal opinion of scholars (Raʾay) - represented by Hanafis. But there also exists one other school of thought known as Shafi school of thought which you can say is mid of these two extremes.

In the early stages of Islamic theology, scholars mainly used methods from traditional Islamic sciences like Qurʾān interpretation (tafsīr), grammar, ḥadīth, and law (fiqh). This was because many of the early theologians were jurists, and mastering these subjects was essential for legal reasoning.

Contact with Greek Ideas

As Muslims expanded into regions like Iraq and Persia, they came into contact with Greek-influenced Christian schools, especially those established by the Sassanians. One of the most famous was the school of Jundishapur. There were also non-Christian centers of learning, like the Sabians of Harran—incidentally, the hometown of Ibn Taymiyya. In these areas, Syriac and Greek were the main languages of scholarship.

Muslim scholars soon found themselves debating educated non-Muslims who challenged Islamic beliefs. To respond effectively, they needed to use reasoning that was accepted across different cultures and intellectual traditions. Christian theology, shaped by centuries of Greek philosophy—especially Neoplatonism, Aristotelian logic, and Stoic ethics—was expressed in a refined and complex way.

As a result, Muslim theologians began adopting Greek ideas and methods, especially tools like formal debate and logical argumentation. These although helped them defend Islamic beliefs but laid the foundation for the development of Mutazilla and kalām.

Key Debates

The first such debate revolved around the question of free will and determinism and influenced the manner in which various other questions of dogma were conceived and debated. Advocating for the position of complete free will were the Qadarīs. The early Muʿtazila subsequently adopted the Qadarī thought, one in which human moral responsibility was held to depend on the fact that men not only chose and performed (faʿala) their actions but positively "created" (khalaqa) them as well. This view was widely denounced as compromising the unique status of Allah as Creator (khāliq). The opposite, "Jabrī" impulse tended towards a strict determinism and categorical denial of human free will.

Another debate was the createdness of Qurʾān, which was supposed to answer whether the Qurʾān is eternal or created by Allah. First formulated by al-Jaʿd b. Dirham and subsequently propagated by his student, Jahm b. Ṣafwān, the notion that the Qurʾān was not eternal but created may have been an attempt to safeguard the notion of God's exclusive eternity in the face of Christian claims of Jesus's divinity on the basis of his status as God's word (kalimat Allāh) in Qurʾān - which although linguistically means word from Allah. It was deemed so pernicious a doctrine that it served to justify the execution of both al-Jaʿd b. Dirham and Jahm b. Ṣafwān.

The Translation Movement

The influence of Greek ideas on Muslim thought came primarily in the form of Arabic translations of the Greek philosophical works, made directly from Greek originals or from intermediate Syriac translations. Although some Greek works particularly medical and scientific treatises were translated in late Umayyad times, it was not until well after the consolidation of Abbasid rule that the large-scale project of translation came into full swing. The capital of the Muslim umma moved from Damascus to Baghdad. Under the new order, religious knowledge and its cultivators received new prominence as the Abbasids explicitly promoted themselves as the defenders of a multiethnic and specifically Islamic order meant to supersede the Umayyad order, which was based on the ethnic favoritism of Arabs.

So we can draw the following timeline:

1. Flourishing of the majority of Muʿtazilī theology happened with translation movement during 850 C.E.
2. Miḥna (in around same time) instituted by three consecutive Abbasid caliphs in an attempt to impose the Muʿtazilī doctrine of the createdness of the Qurʾān as official doctrine.
3. Ibn Kullāb active, shunning Muʿtazilī doctrine, formulating early rational thoughts.
4. The caliph al-Wāthiq turns on the Muʿtazila, ends the miḥna, and reinstates Sunnī orthodoxy. Aḥmad b. Ḥanbal emerges as a hero for his refusal to accept Muʿtazilī ideas during Miḥna.
5. Al-Ashʿarī [10th Cent.] (Original creator of Ashʿarī Creed) breaks from the Muʿtazila at age forty but uses their rational method to launch a full-fledged defense of orthodox creed with rational arguments. His next generation follower Al-Bāqillānī brings the doctrine to peak value in its followings.
6. Flourishing of al-Juwaynī [11 Cent.], first Ashʿarī theologian under Ibn Sīnā's (and thus Aristotle's) influence. Considered a crossover figure between early and later Ashʿarī school.
7. In 12th Cent., Al-Ghazālī fully accepts Tawil (Ashari Interpretation) launching attack on Aristotelian Philosophy along with articulating Universal Rule and Ibn Rushd defends Aristotelianism and responds to al-Ghazālī. Writes Faṣl al-maqāl on the necessity of upholding the literal sense of revelation for the common people while reserving the real truth, gained through reason, for the philosophical elite.
8. Flourishing of Fakhr al-Dīn al-Rāzī in 12th Cent. an Ashʿarī who formulated Universal Rule for ending the conflict of Reason and Revelation.
9. Ibn Taymiyya a Hanbali theologian, writes Darʾ taʿāruḍ against Universal Rule of al-Rāzī.

The Muʿtazilī Era

The origin of Muʿtazilī thought is normally attributed to Wāṣil b. ʿAṭāʾ—who is said to have separated from (iʿtazala) the circle of al-Ḥasan al-Baṣrī over the question of the status of the grave sinner.

In terms of methodology, the early Muʿtazila seem to have relied principally on the styles of reasoning and argumentation that had been developed in the indigenous Islamic sciences of Arabic grammar and law, as well as Qurʾān exegesis and ḥadīth. Eventually, however, the mature Muʿtazilī school reinforced its intellectual armature by adopting numerous aspects of Greek reasoning.

Central to Muʿtazilī theology are the five foundational principles (al-uṣūl al-khamsa), which show their distinctive theological stance. Among these, the concept of tawḥīd—the absolute oneness of God—occupies a pivotal role. The Muʿtazilī interpretation of tawḥīd involves three key assertions: first, the rejection of the distinctiveness of God's attributes, such as knowledge, power, and speech, which they viewed as inseparable from His essence; second, the denial of the Qurʾān's eternality (qidam), affirming instead that it was created in time to preserve the uniqueness of God's Speech; and third, the radical affirmation of tanzīh, the incomparability of God, which insists that no created thing can resemble the divine in any way.

The Muʿtazilī thinkers were not only known for their five main principles, but also for their strong desire to defend Islamic beliefs against the arguments of other religions. They used reason and logic to explain and protect their faith. However, most Sunnī scholars saw the Muʿtazila as heretics, so their ideas were not accepted directly into mainstream Islamic thought. Instead, their influence was more subtle and indirect. A later scholar, Ibn Taymiyya, believed that this hidden influence caused many problems in Islamic theology.

Even though the Muʿtazilī school eventually lost its popularity, it still shaped the way Islamic theology developed—especially the kinds of questions scholars continued to ask. In contrast, many scholars preferred a simpler, non-speculative approach to theology, which became closely linked to the Ḥanbalī school. This style avoided philosophical reasoning and focused more on the Qurʾān and ḥadīth they were the ahl al-ḥadīth, who rejected Muʿtazilī methods but still offered clear views on major theological issues. The most famous among them was Aḥmad ibn Ḥanbal, founder of the Ḥanbalī legal school. Ibn Taymiyya, who followed this school, greatly admired Ibn Ḥanbal's sharp thinking. Modern scholars like Watt says in his work "Formative Period" about him, "he [Ḥanbal] was clearly a man of powerful intellect capable of adopting a coherent view in matters of great complexity."

End of Miḥna

In the early third/ninth century, a major conflict erupted between two theological approaches in Islam. On one side stood the Muʿtazila and on the other side were traditionalist scholars—founders of the major Sunnī legal schools and experts in ḥadīth—who insisted on sticking closely to the plain meaning of scripture and avoiding speculative reasoning.

This clash reached its peak during the infamous miḥna, or "inquisition," launched by the Abbasid caliphs. Religious scholars, especially in Baghdad, were forced to publicly declare that the Qurʾān was created (makhlūq) and not eternal (qadīm), a key Muʿtazilī belief. Those who refused faced harsh punishment—imprisonment, beatings, and even death. One of the few who stood firm was Aḥmad ibn Ḥanbal hence his resistance made him a symbol of defiance against enforced theology by caliphs.

The tables turned in 232/847 when Caliph al-Mutawakkil came to power. He ended the miḥna, removed the Muʿtazila from their positions, and began a process that led to their decline. In the aftermath, a new group of theologians emerged in Baghdad. They were close to Ibn Ḥanbal's views and included scholars from the Ḥanafī school and others who had rejected Muʿtazilī methods. These scholars refused to debate theology using the speculative tools of kalām.

One notable figure from this group was al-Ḥārith al-Muḥāsibī, an early Sufi and contemporary of Ibn Ḥanbal. Although he was a traditionalist, his engagement with kalām even to refute it angered Ibn Ḥanbal, who saw any use of its methods as dangerous and misleading. (see Picken, "Ibn Ḥanbal and al-Muḥāsibī.")

Another influential theologian after the miḥna was ʿAbd Allāh ibn Kullāb. He helped for the acceptance of kalām among mainstream Sunnīs. While his beliefs were close to those of the Ḥanbalī traditionalists, his methods laid the foundation for what would later become standard in Ashʿarī theology.

Ashʿarī Creed

This story begins with Abū al-Ḥasan al-Ashʿarī who was said to be a descendant of the Prophet's Companion, Abū Mūsā al-Ashʿarī. He studied religious sciences in Baghdad and became the top student of the leading Muʿtazilī scholar, Abū ʿAlī al-Jubbāʾī. Around the age of forty, al-Ashʿarī is said to have had a dream in which the Prophet told him to defend the Sunna as passed down through ḥadīth. After this, al-Ashʿarī publicly rejected Muʿtazilī beliefs, gave up kalām (speculative theology), and focused only on the Qurʾān and ḥadīth.

Later it is said that, he had another vision where the Prophet corrected him, saying that while he should defend the Sunna, he didn't need to abandon rational methods. So, al-Ashʿarī began using reason to defend Islamic beliefs. He argued that the Qurʾān itself included some rational ideas, similar to those used by the Muʿtazila. He used these tools to argue against both Muʿtazilī ideas and extreme anthropomorphism (tajsīm), which gave human-like qualities to God.

Al-Ashʿarī's approach allowed limited comparison between God's attributes, using a softened version of the Muʿtazilī method of analogy (qiyās al-ghāʾib ʿalā al-shāhid), which means learning about the unseen world by comparing it to what we see. He tried to find a middle path between the Muʿtazila's rationalism and the strict literalism of the Ḥanbalīs.

However, many Ḥanbalīs rejected al-Ashʿarī and his followers because they believed using kalām was dangerous. Like their leader Aḥmad ibn Ḥanbal, they preferred to stick to the plain meaning of scripture without asking how or using analogy.

Al-Ashʿarī's theological treatise al-Ibāna ʿan uṣūl al-diyāna a work against strict Ḥanbalīs, which Ibn Taymiyya also considered to be his last work on theology, represented his final view on theological matters. It is not until the second generation after al-Ashʿarī that we encounter three other, prominent figures who took up al-Ashʿarī's torch.

The first of them was, al-Bāqillānī who is reported to have studied kalām under two of al-Ashʿarī's direct students. Al-Bāqillānī built on al-Ashʿarī's ideas and made them clearer and stronger. He introduced a strict rule called the principle of reversibility. This meant that if a proof was wrong, then the idea it was trying to support must also be wrong. This helped make arguments more solid and reliable.

Hence, al-Bāqillānī is seen as the most important figure in organizing and shaping early Ashʿarī theology, known as the way of the mutaqaddimūn (the early scholars). In a way, he was also the last of that early style, because after him, starting with al-Juwaynī, big changes began that led to a new kind of Islamic theology called "new kalām" which was the beginning of philosophical beliefs incorporation in Ashʿarī theology.

Rise of Philosophy

Philosophical reflection began early in the intellectual career of Islam. The Arabic-Islamic philosophical tradition, called falsafa, began in the Muslim world through the translation of Greek texts. It was mainly based on the works of Aristotle and his later interpreters. Most of these interpreters were Neoplatonists—except for Alexander of Aphrodisias, who followed Aristotle more strictly.

Neoplatonism played a major role in shaping Muslim philosophy. Many of its ideas influenced later thinkers, but some of these ideas were strongly criticized by Ibn Taymiyya. To understand his objections, we first need to look at how philosophy challenged Islam, so we need to discuss about philosophers.

Abū Yūsuf Yaʿqūb al-Kindī (d. around 866), known as the "philosopher of the Arabs," was educated in Kufa and worked in Baghdad under the support of three Abbasid caliphs—those same rulers who had enforced the miḥna (a kind of religious inquisition). Al-Kindī tried to make philosophy more acceptable to Muslims by promoting harmony between reason and faith.

Writers from different backgrounds agree that al-Kindī aimed to connect philosophy with religion. He believed that rational thinking could be used to understand religious texts. His views were often close to those of the Muʿtazila. However, he also criticized some of their ideas, like their theory of atomism.

Interestingly, al-Kindī's idea of God as the cause of everything in the universe resembles the Neoplatonic idea of the One, though he adapted it to fit Islamic beliefs about God as the Creator.

Some say al-Kindī saw God as just pure oneness, but others argue he believed God has real qualities—like being powerful and generous. He saw God not just as an idea, but as someone who acts.

Farabi, another leading philosopher of his time, born in Farab (located in current-day Turkmenistan), Abū Naṣr Muḥammad al-Fārābī (d. 950) spent most of his life in Baghdad, where he studied logic under the Nestorian Christian scholars Yūḥannā b. Ḥaylān. It is primarily his work on logic, however, that earned him the epithet "the Second Teacher" (al-muʿallim al-thānī) second only to the First Teacher, Aristotle.

Al-Fārābī is credited not only with writing the "first systematic exposition of Neo-Platonism in Arabic" but also, indeed, with laying the foundations of the mainstream tradition of Islamic philosophy. (See the work of Mahdi, Al-farabi and the Foundation)

Also relevant to the topic of reason and revelation is the fact that al-Fārābī, like al-Kindī before him, also dealt with the relationship between philosophy and religion, casting this discussion in terms that were later closely echoed by Ibn Sīnā.

He explicitly called for the allegorical reinterpretation of scripture in instances in which the literal meaning conflicts with reason.

Another leading scholar, Ibn Sīnā, also known as Avicenna, was a major thinker in Islamic philosophy. Before him, two types of thought—philosophy and kalām (Islamic theology)—were mostly separate. Ibn Sīnā combined them, and after him, kalām included many of his ideas. With Ibn Sīnā, the two strands became intertwined to such an extent that post-Avicennian kalām came to represent a synthesis of Ibn Sīnā's metaphysics and Islamic theological doctrine.

He believed logic was the key to understanding the true nature of things. This idea was later criticized by Ibn Taymiyya.

Ibn Sīnā also had a unique view of God. He said God exists by Himself and everything else comes from Him by necessity. This view was different from traditional Islamic belief, which says God freely created the world by choice.

Al-Ghazālī, disagreed with Ibn Sīnā and wrote his famous work "The Incoherence of the Philosophers", where he argued against Ibn Sīnā's ideas, especially the belief that God does not know individual things in the world.

Development of Philosophy Under Later Ashʿari Scholars

In the 11th century, Islamic theology began to change because of the strong influence of Ibn Sīnā's philosophy. Even though theologians had already borrowed some methods from philosophers, the main topics in kalām (Islamic theology) stayed the same for about 300 years.

This changed after Ibn Sīnā, when new thinkers like al-Juwaynī and his student al-Ghazālī brought a fresh approach to kalām. For about 200 years, from al-Kindī to Ibn Sīnā, philosophy had grown quickly and started to challenge traditional theology.

This sudden rise of philosophy made it clear that Ashʿarī kalām, which was first created to respond to the Muʿtazila group, wasn't strong enough to handle the new philosophical ideas.

Abū al-Maʿālī al-Juwaynī (also known as "Imām al-Ḥaramayn," d. 1085) was the first major Ashʿarī theologian directly influenced by the philosophy of Ibn Sīnā. He noticed that traditional kalām (Islamic theology) was not strong enough to respond to philosophical challenges. To fix this, al-Juwaynī carefully chose parts of philosophy that he believed were not only compatible with kalām, but also necessary to support its worldview against Ibn Sīnā's powerful ideas.

Al-Juwaynī's views on rational sciences changed over time. He believed that naẓar - the act of thinking deeply and rationally about the foundations of faith, was a duty for every Muslim who had reached maturity. According to him, this process was required for a person's faith to be valid. This idea is clearly shown at the beginning of his book Kitāb al-Irshād, as noted by Gardet and Anawati.

Though al-Bāqillānī had harbored reservations about the analogical inference from the seen to the unseen (al-qiyās bi-l-shāhid ʿalā al-ghāʾib) and had tried to reinforce the defensive arsenal of kalām by adding to it his principle of reversibility. Al-Juwaynī completely abandoned both the analogy and the reversibility principle of al-Bāqillānī. In their place, he incorporated new logical techniques such as enumeration and division (al-sabr wa-l-taqsīm) [i.e deciding by "yes or no" options] and the method of disjunction between affirmation and negation. These tools enhanced the logical framework of kalām, supplementing the existing methods of indirect syllogism (qiyās al-khalf) and direct syllogism (al-qiyās al-mustaqīm).

In his final book, al-ʿAqīda al-Niẓāmiyya, al-Juwaynī changed how he argued for the existence of God. He stopped using the older method from kalām, which was based on the idea that the world was created and had a beginning (called ḥudūth al-ajsām, or the origination of bodies). Instead, he used Ibn Sīnā's approach, which focused on the difference between things that must exist (wujūb) and things that could exist but don't have to (imkān). This shift marked a major change in Islamic theology. It showed how logic was becoming more important in religious thinking. Because of this, later scholars began to separate early kalām (by the mutaqaddimūn, or earlier thinkers) from later kalām (by the mutaʾakhkhirūn, or later thinkers).

Al-Juwaynī also seems to be the first Ashʿarī theologian to include the Muʿtazilī idea of atomism—the belief that everything is made of tiny indivisible parts (but not that simple) into Ashʿarī kalām.

Another crucial departure from al-Ashʿarī's methodology in the work of al-Juwaynī, which also concerned Ibn Taymiyya, was his view on God's attributes. Earlier scholars like al-Ashʿarī and al-Bāqillānī followed the idea of bi-lā kayf—accepting the Qurʾān's descriptions of God without asking how, in order to protect both Allah's greatness and the literal meaning of the Qurʾān.

Al-Juwaynī went further. He divided God's attributes into two types: essential (nafsī) and qualitative (maʿnawī). This was seen as a move toward a more flexible or "liberal" Ashʿarī theology, less focused on taking Qurʾānic descriptions literally.

He was also one of the first Ashʿarī scholars to use figurative interpretation (taʾwīl) for certain revealed attributes (al-ṣifāt al-khabariyya)—like God's hands or face. These are mentioned in the Qurʾān using words that might suggest physical form, but al-Juwaynī believed they should be understood in a symbolic or non-literal way, since they can't be known through reason alone.

In the new logic on the basis of which al-Bāqillānī's reversibility principle is rejected, however, the Aristotelian syllogism becomes predominant. This "new method" which incorporates the new logic as well as the new argument for the existence of God, both compliments of Ibn Sīnā became predominant after al-Juwaynī [For understanding differences between old and new kalam, read Gardet and Anawati, Introduction].

The next in this series of Ashʿari scholars is, the "Proof of Islam" (Ḥujjat al-Islām) Abū Ḥāmid al-Ghazālī (d. 505/1111) a watershed figure in Islamic intellectual history whose thought represents a mix of jurisprudence, theology, philosophy, and Sufism and who rightfully deserves a separate discussion in relation to each of these fields. Al-Ghazālī's refutation of certain central theses of the philosophers on purely philosophical grounds (similar to Ibn Taymiyya's refutations) but also from his adoption of certain elements of philosophy that he made part and parcel of Islamic orthodoxy.

Al-Ghazālī studied in Nishapur under the eminent Imām al-Ḥaramayn al-Juwaynī. He then taught at the prestigious Niẓāmiyya madrasa in Baghdad for four years. During this period, he produced a number of important works, including an exposition of logic, Miʿyār al-ʿilm fī fann al-manṭiq (The standard of knowledge in the art of logic), and an important work of Ashʿarī theology, al-Iqtiṣād fī al-iʿtiqād (The just mean in belief).

He wrote his most celebrated work, Iḥyāʾ ʿulūm al-dīn (The Revival of the Religious Sciences), after a lengthy period of solitary travel dedicated to treading the Sufi path of spiritual purification and mystical realization. Upon returning home from this extended hiatus he wrote Tahāfut, where al-Ghazālī charged the philosophers with relying on inherited assumptions that cannot be deduced apodictically. Thus al-Ghazālī's was the first, though not the last, attempt in Islam to respond to philosophy.

Indeed, it is well known that while al-Ghazālī rejected many aspects of philosophy entirely, most notably its precarious metaphysics, he nonetheless enthusiastically embraced the Aristotelian logic built on definition and syllogism that forms the core of the entire system. [See Introduction of Hallaq's Greek Logicians] In his enthusiasm for this powerful new tool of logic, al-Ghazālī even believed he could identify in the Qurʾān a prefiguring of the five forms of the Aristotelian syllogism.

Regarding the metaphorical interpretation of texts, al-Ghazālī accepted the use of taʾwīl, in the manner of al-Juwaynī, to obviate overtly anthropomorphic readings of the ṣifāt khabariyya, or "revealed attributes" (hands, face, etc.) but he insisted that such taʾwīlāt should remain with the elite and not be discussed among the general populace for fear of inducing confusion in their minds.

In the Iḥyāʾ ʿulūm al-dīn, al-Ghazālī exhibits a guarded attitude towards kalām, admitting that it was not practiced by the earliest generations of Muslims but nevertheless conceding a limited use of it as indispensable for combatting heretical innovations (bidaʿ) that risked leading believers away from the path of the Qurʾān and Sunna.

The inherent limitations of kalām, as al-Ghazālī instructs us in his work al-Munqidh min al-ḍalāl (Deliverance from Error), lie in the fact that it proceeds on the basis of ideas that are not rationally certain in and of themselves since they must be accepted on the basis of revelation or the consensus (ijmāʿ) of the community; For al-Ghazālī, true certainty (yaqīn) can ultimately be gained only through the "witnessing of realities" (mushāhada, or mushāhadat al-ḥaqāʾiq) by way of spiritual unveiling (kashf).

Post-Ghazālīan Fate of Philosophy

As we may expect, the most vociferous opposition came from Ḥanbalī quarters — an example being ʿAbd Allāh al-Anṣārī al-Harawī (d. 481/1089), a Ḥanbalī and well-known Sufi who attacked the Ashʿarīs vigorously.

It was not until the famous Seljuq vizier Niẓām al-Mulk (active 455–485/1063–1092) established positions in the major madrasas of the empire specifically to teach the new theology that the Ashʿarī school was finally able to triumph over its two rivals: the Muʿtazila, on the one hand, and the strictest of the Ḥanbalīs, on the other.

By the time Ibn Taymiyya was born some two hundred years later, any significant opposition to kalām theology had all but dissipated in most quarters. Ashʿarī kalām had long since been accepted by much of the Sunnī world as the normative, orthodox expression of Islamic belief in rational-theological terms.

The Ultimate Fate of Philosophy

On the ultimate fate of philosophy as an independent pursuit in the Islamic world, Tim Winter concludes that: "falsafa as a discipline was progressively overtaken, or perhaps swallowed up, by Sunnī kalām at some point after the twelfth century. Perhaps the reason for this was the same factor which had caused the translation movement to wind down two centuries earlier: the ideas had been successfully transmitted. Falsafa functioned as an intermediary school, a module provisionally and imperfectly integrated into Muslim culture which allowed Muslim thinkers to entertain Greek ideas and choose those which seemed to them persuasive and true. As a system, however, it did not possess the resources to survive indefinitely. Once Muslims found that their need for a sophisticated philosophical theology was satisfied by the kalām, falsafa as an independent discipline naturally withered."

And as this article is reaching its end, the final character who formulated the "Universal Rule" must be discussed.

Fakhr al-Dīn al-Rāzī: Architect of Philosophical Theology

Fakhr al-Dīn al-Rāzī who is one of the main architects of this new "philosophical theology" in the century immediately after al-Ghazālī was the Persian Shāfiʿī theologian and polymath Fakhr al-Dīn al-Rāzī (d. 606/1209).

It is al-Rāzī who, coupled with al-Ghazālī, did the most to incorporate the new philosophical approach into the body of kalām. [See Watt, Islamic Philosophy and Theology p. 94]

Al-Rāzī immersed himself in the study of philosophy and was a master of the art of disputation. His thought was highly influenced by Ibn Sīnā, but mostly in the way of the philosopher Abū al-Barakāt al-Baghdādī (d. 560/1164 or 1165), a convert from Judaism to Islam whose thought, while steeped in that of Ibn Sīnā, was nevertheless critical of the latter and whose views, on the whole, were closer to orthodox Muslim (and Jewish) theological positions.

Al-Rāzī's Major Work

Al-Rāzī's most important work on theology, Muḥaṣṣal afkār al-mutaqaddimīn wal-mutaʾakhkhirīn min al-ʿulamāʾ wa-l-ḥukamāʾ wa-l-mutakallimīn (The harvest of the thought of the ancients and moderns among scholars, philosophers, and theologians), which clearly shows the increasing influence of the terms and categories of philosophy in the discourse of kalām and the first inclusion of metaphysical preamble in kalām.

Al-Rāzī's Interpretation of Ibn Sīnā

Heidrun Eichner explains that Fakhr al-Dīn al-Rāzī played a major role in how later Muslim thinkers understood the ideas of Ibn Sīnā (Avicenna), especially about existence and reality. One of al-Rāzī's books, The Epitome on Philosophy and Logic, became very influential from the late 1200s onward. But al-Rāzī didn't just repeat Ibn Sīnā's ideas—he often explained them in order to challenge or offer different views. Sometimes, he didn't describe Ibn Sīnā's ideas accurately or used words that didn't quite fit.

One of al-Rāzī's key beliefs was that existence is something added to a thing's essence. This idea was later criticized by Ibn Taymiyya, who saw it as a mistake common among certain philosophers. Al-Rāzī held this view even though it went against the teachings of al-Ashʿarī, a major Islamic theologian. Still, al-Rāzī's goal was to defend the belief that God created the world by choice, not automatically as Ibn Sīnā's ideas might suggest.

Tariq Jaffer has dedicated a full monograph to al-Rāzī in which he elaborates in depth on al-Rāzī's endeavor to establish Islamic (specifically Ashʿarī) theology on the most solid rational foundations possible. Significantly, al-Rāzī undertakes this ambitious project not merely by means of the received medium of the formal theological or philosophical treatise but even more so through his massive, 32-volume Qurʾānic commentary, Mafātīḥ al-ghayb (Keys of the unseen), also known simply as al-Tafsīr al-kabīr (The grand tafsīr). Jaffer argues that "by using the Qurʾān to express his philosophical theology, Rāzī gave his revolutionary agenda an undisputed authority in Sunnī Islam." [See Jaffer on Razi]

Ibn Taymiyya is reported to have quipped that "this massive work contains everything but tafsīr".

We'll discuss about Universal Rule and Ibn Taymiyaa's view on it in our next article, InshaAllah!

This work builds upon my reading of, "Ibn Taymiyya on Reason and Revelation" by Carl Sharif El-Tobgui

Allah-Hafiz!