A Critical Examination of Kierkegaard’s Fideism from the Perspective of Nasir al-Din al-Tusi

This article comparatively examines the relationship between reason and faith in the thought of Søren Kierkegaard and Nasir al-Din al-Tusi through an analytical-comparative method. Its central question is whether religious faith stands in conflict with reason or whether the two can be understood as mutually complementary. Kierkegaard, reacting to systematic rationalism and Hegelian interpretations of Christianity, stresses the existential, personal, and passionate character of faith. For him, faith is associated with paradox, personal decision, and a movement beyond objective rational guarantees. Accordingly, Abraham’s story represents the teleological suspension of the ethical in the context of the individual’s absolute relation to God. By contrast, al-Tusi regards reason as a valid instrument of religious knowledge and as complementary to revelation. Within his intellectual framework, reason is capable of demonstrating fundamental theological principles, including God’s existence and certain divine attributes, although it remains limited with regard to the divine essence and the details of religious law, which require revelation. The study argues that an absolute opposition between reason and faith, as suggested by some Kierkegaardian formulations, does not provide an adequate account of religious faith. Faith possesses not only existential and affective dimensions but also cognitive and practical ones. Drawing on al-Tusi’s principles, the article proposes a reconstructed model of faith in which rational reflection, existential passion, religious trust, and ethical action function as complementary elements. Thus, faith is neither merely abstract knowledge nor an irrational decision devoid of rational grounding; rather, it is a dynamic process integrating knowledge, inward commitment, and action.