The decisive difference between Ibn Taymiyya and opponents such as al-Ghazali and Fakhr al-Din al-Razi is not about whether reason is a foundation (asl) of revelation –
they all agree that it indeed is – but what claims follow from that. Ibn Taymiyya clarifies this only late in his work, namely at the beginning of the 34th viewpoint (wajh) of his Dar’ T’aarud al-‘aql Wa al-Naql:
“Those who oppose revelation and prioritize their opinion over what the Messenger conveys, they [also] say: “Reason is the foundation (asl ) of revelation. If we prioritized revelation over reason, this would mean the dismissal of the foundation of revelation.” This statement is indeed correct on their part (sahih) if they acknowledge the truth (sihhat) of revelation without objecting [to it].”
From the fact that revelation relies on reason in order to be identified and to work – so to speak –, al-Ghazali and Fakhr al-Din deduce that it must be understood through the parameters of the same reason that makes it work. It is this claim that Ibn Taymiyya denies. Ibn Taymiyya hence denies the second step in our reconstruction of Fakhr al-Din’s argument and not the initial premise of reason being the foundation (asl) of revelation. Like his opponents, he needs reason to identify revelation, but once that has happened he is no longer in need of it, at least as far as theology is concerned, and claims that what can be known in theology must be taken from revelation.
So far so clear. This dispute, however, is complicated by the fact that with regard to certain objects of theology, Asharites such as al-Ghazali held the same position as Ibn Taymiyya about the sole authority of revelation. Regarding the afterlife, for instance, al-Ghazali fully agreed with the notion that reason cannot contribute to its knowledge and that it is the sole domain of revelation. Not so, however, when it comes to God’s attributes, where al-Ghazali claims that reason and revelation must be used together.
From this perspective, the dispute between al-Ghazali and Ibn Taymiyya looks like an ordinary disagreement on the bounds of reason, similar, for instance, to the one between al-Ghazali and Ibn Rushd (Averroes, d. 595/1198). Ibn Rushd claimed that metaphysics and theology is a field that is fully subject to demonstrative arguments. Al-Ghazali denied that. In principle, both agreed on their understanding how reasonable arguments are produced and how their conclusions can be verified. They disagreed on how far the authority of reason reaches into such fields as metaphysics. The case looks similar here.
In his dispute with Ibn Taymiyya, al-Ghazali claims that the divine attributes are an object where demonstrative arguments contribute to a human understanding of the divine. Ibn Taymiyya denied it. Hence, Ibn Taymiyya and al-Ghazali disagree about which objects of human knowledge fall into the sole authority of revelation. Their focus point is the divine attributes. Despite all his polemics, however, I would argue that Ibn Taymiyya’s most basic conception about the relationship between reason and revelation is the same as al-Ghazali’s.
Ibn Taymiyya and al-Ghazali, however, disagree on more than just the bounds of reason. Their dispute is further complicated by the fact that they have different understandings of the meaning of the word “reason” (‘aql ). For, al-Ghazali and also Fakhr al-Din, this word refers to an inquiry that is guided by Aristotelian logic and by an Aristotelian understanding of demonstration (burhan). These two expect every credible scholar in Islamic theology and its adjacent disciplines to be firm in Aristotelian logic. Aristotelian logic is the tool that allows scholars like al-Ghazali and Fakhr al-Din to verify their teachings. Aristotle’s “toolbox,” the Organon, teaches among other things the correct formation of definitions and how these definitions are used in prepositions.
These prepositions, in turn, are employed in syllogistic arguments that yield correct conclusions which themselves form the premises of other syllogisms. In the understanding of such scholars as al-Ghazali and Fakhr al-Din, the correct use of Aristotelian logic allows the construction of epistemological edifices that reach to the highest knowledge that is possible for humans and even contribute to our knowledge of God.
This does not hold true for Ibn Taymiyya. In several of his writings, most importantly al-Radd ‘alal-mantiqiyyın and Dar’ taarud, Ibn Taymiyya presents a far-reaching critique of Aristotelian logic that thoroughly undermines any suggestion it could serve as
the basis of whatever epistemological edifice. Definitions, Ibn Taymiyya claims, “define” what is already known to those who use concepts. These definitions do not grasp any
“essences” or “realities” (haqıqah) of the concepts since none of that exists outside of the
human minds. “Genus,” “species,” and “specific differences” are nothing but hollow words that represent artificial distinctions with no grounding in the individuals they are supposed to describe. Syllogisms are formal constrains to a wide variety of arguments that people may find convincing. The Qur’an and the Hadith teach the use of arguments in a much better way than any textbook of Aristotelian logic.
Despite his harsh criticism of Aristotelian logic, Ibn Taymiyya does not deny that
there are rules that govern the right conduct of human reason*. These, however, are not those taught in the textbooks of logic written by Ibn Sına, al-Ghazalı, or Fakhr al-Din al-Razı. Rather, the correct rules are those that are encompassed in what Ibn Taymiyya calls the human fitra. They can be learned, for instance, from revelation, which is a manifestation of the correct use of reason. The correct use of reason verifies the truth of revelation and revelation verifies the right use of reason.
It is the circle in Ibn Taymiyya’s theology that claims that natural reason* (or “uncontaminated reason”) reaches the very same results as those that we find in revelation. Given, however, that for Ibn Taymiyya and his modern followers there is no method of verifying reason* which is independent from revelation, we have no way of really knowing what reason* actually teaches other than taking it from revelation. For his Asharite opponents, logic, the method of demonstration (burhan), and the formal rules of arguing provide a method of verifying the judgments of reason which is indeed independent of revelation. Ibn Taymiyya’s rejection of formal logic, however, and his failure to put something in its stead that does not itself depend on revelation, deprives him of that independent verification and leads to the circularity that I think characterizes his thought and that of many of his followers.