THE THEOLOGY OF MATHEMATICS: REASON, AUTHORITY AND AFTERLIFE

In 2006, Pope Benedict XVI made a strong statement in his Regensburg Lecture while discussing about forced religious conversion which was “not to act on the basis of reason is contrary to the divine nature”. Similarly, Theodore Khoury who was a Lebanese Catholic theologian and historian of Christianity and Islam, observers that Christianity is related with Greek rationality, whereas Islam, by placing God beyond the limits of reason turns into a violent ideology. 

When these claims are examined closely, it reveals that he is emphasizing the nature of Islam and Christianity (relationship with reason), not their theological content. So, the deciding factor of Islam is associated with violence and Christianity with legitimacy is based on the reason.

He is trying to defend Christianity by prioritizing reason itself by this move. This raises a crucial question: how does reason take precedence over theology? Why does a tradition like Christianity that once was the ideological backbone of empires, have to use reason in this way to justify itself through confirming rationality? 

“Reason” is a broad concept which is inseparable from human thought. Thinking is a natural process to human beings; it shapes everyday life and quietly decides our judgments of what is just and unjust, right and wrong. On the other hand, Thought is not a specialized activity but an integral part of being human.

However, thinking is subjected to undergoes a more rigorous process when it is restructured to reason-centred thought, of observation, experimentation, evidence, and methodical verification. This way of thinking process that modern science supports and institutionalizes. Mathematics has a privileged consideration in this framework. Reasoning and logic are two branches of mathematics that serve as the main foundations of logic.

As per Benedict’s previously mentioned statement, it is necessary to consider the ways in which religious authority has used reason. So, this article looks to mathematics which includes the foundations of logic and its relationship with theology, and the transformations occurred over time, and the power mathematics has gradually acquired over theological discourse.

 Theology and Mathematics

 The Russian scholar Vladislav Shaposhnikov examines how much theological presumptions has permeated contemporary philosophies of mathematics in his two-part book “Theological Underpinnings of Modern Philosophy of Mathematics”. 

In ancient-medieval intellectual traditions, mathematics was always associated with theology. For instance, the Neoplatonist thinker Iamblichus associated numbers with divine realities, treating them not only as abstract quantities but also as expressions of metaphysical order. Following this, many in the Christian tradition associate the divine order of creation and maintenance with mathematical harmony (or the argument that the world order exists through patterns and relationships). Medieval thinkers such as Eriugena and Otloh went far more by linking numbers to supernatural realities, entering to the field of “mathematical angelology.” In this framework, numbers functioned as mediators between the divine and the created world. In short, the conviction that God created the universe according to mathematical principles was a widely accepted from Plato to early modern thinkers such as Kepler, Galileo, and Descartes.

Later, in the nineteenth century, a decisive process of secularization takes place, gradually removing theology from its position within intellectual life. This can be found in Auguste Comte’s classification of the scientific subjects, where theology-long regarded as the highest form of knowledge-is displaced and mathematics is upgraded to supreme scientific discipline. As a result, mathematics is compelled to prove attributes like absoluteness, completeness, universality, and infallibility that were traditionally associated with theology. In this sense, mathematics does not merely replace theology; it inherits the burden of its former authority.

 In this context a new concept referred to as the “Popular Philosophy of Mathematics” begins to take shape. In order to replace theology as the highest source of certainty, mathematics presented a set of foundational qualities.

They can be summarized as follows:

 1. Mathematics is certain and infallible.

 2. It is necessary and universally valid.

 3. It is constant and precise.

 4. It is free and autonomous.

 5. It is universally applicable.

 It can be read from intellectual history that these five principles attributed to mathematics within popular philosophy were actually formulated to establish mathematics as a discipline capable for competing theology in authority. Therefore unsurprisingly, by the nineteenth century, many of these claims began to face serious challenges. Mathematics was presented as complete and absolute, but the reality is Mathematics lacked the kind of foundational acceptance that theology had historically enjoyed. This became one of the main reasons for crisis within mathematical thought.

 The claim of universal applicability was not easy to prove. When it comes to practical reality, Mathematical principles could not always be seamlessly gained. As a result, the universal validity occasionally nuanced into limitation or incompleteness. These challenges pushed mathematics into deep philosophical struggles and separated pure mathematics from empirical and theological foundations. But by the 20th century, various movements such as logicism-Bertrand Russell, formalism-David Hilbert, intuitionism-L. E. J. Brouwer, emerged as competing attempts to resolve the foundational uncertainties of mathematical knowledge. 

 This is where Shaposhnikov’s argument becomes especially significant; that even after the rise of mathematics through secularization, its completeness and indubitability continued to be questioned against theology. More importantly, even the intellectual movements that emerged to resolve mathematical uncertainty reveal unmistakable theological traces.

 The Logicism proposed by Bertrand Russell presents mathematics as an ultimate and immutable system, aspiring to an almost absolute form of certainty. By contrast, Hilbert’s formalism understands the power of human reason as a religious faith rather than a theological certainty. The third major development, Intuitionism, moves in a very different direction which emphasizes mysticism. For Brouwer, Intuitionism is something that relies on the internal and subjective basis of time rather than classical logic. For example, mathematical truth is not an independent, static entity—as theology once was—but a dynamic and evolving reality discovered through personal, inner experience. It is precisely this experiential and inward orientation that allows intuitionism to be meaningfully compared with mysticism. Thus, Brouwer’s later writings make it clear how much intuitionism has developed theologically.

From this perspective, even if Shaposhnikov’s claim that modern mathematics has a theological influence is correct, yet a crucial question remains unresolved: who has authority here? When theology once held epistemic supremacy, mathematics was used to support of theological certainty. But after secularization theology loses its supremacy, and mathematics itself emerges as an independent power. This shift of authority makes it suitable for scholars such as Pope Benedict XVI to consider reason as the authority to validate Christian theology. Whether consciously or unconsciously, such an appeal presupposes the post-secular authority that mathematics—and the form of rationality it represents—has come to command.