Rational proofs of tawheed belief in Islamic philosophers (The example of al-Ghazālī)

According to the science of Kalām, the beings in the universe, as well as the events and phenomena that occur, point to the existence and oneness of God. Human beings, in order to make sense of these events and phenomena, have always been in a state of constant search. Throughout history, as a result of this search for meaning, different conceptions of God have emerged. Some of these conceptions were grounded in the existence and oneness of God, while others leaned toward animistic or polytheistic understandings of the divine. According to Islamic belief, in order to correct these false conceptions of God, Allah intervened in history by sending revelation through His prophets. However, while inviting their communities to believe in the existence and oneness of God, the prophets did not limit themselves to the revealed message but also made use of numerous cosmological and rational arguments that pointed to God's existence and unity. The final prophet, Muhammad (peace be upon him), as the last link in the chain of prophethood, invited all of humanity to the true faith and religion. After him, many scholars who embraced the principle of tawḥīd struggled against shirk (polytheism) through their ideas and sought to respond to the problems of belief in their own times. These scholars, in defending the principles of Islamic faith and values, employed numerous arguments related to tawḥīd, one of the fundamental structures of religion. In order to establish the principle of tawḥīd and defend the tenets of Islamic belief, they relied not only on transmitted (naqlī) proofs but also on rational (ʿaqlī) arguments. This study aims to examine Abū Ḥāmid Muḥammad al-Ghazālī's (d. 505/1111) efforts to prove the doctrine of tawḥīd in light of rational arguments. As both a mutakallim (theologian) and a philosopher, al-Ghazālī, unlike his predecessors, employed both methods together. While affirming that God's power is infinite and that the true agent is God alone, he argued that causality is not necessary and criticized the Aristotelians. With this approach, it may be said that he sought to ground a transmitted (naqlī) issue within rational and philosophical thought. It has been identified that al-Ghazālī, in order to establish the principle of tawḥīd upon a solid foundation, employed arguments such as possibility (imkān), origination (ḥudūth), innate disposition (fiṭra), purpose and order (ghāya wa-niẓām), the proof of mutual hindrance (burhān al-tamānuʿ), and the proof of convergence (burhān al-tawārud). This thesis highlights the significance of al-Ghazālī's efforts to explain the principle of tawḥīd through rational arguments. In conclusion, al-Ghazālī demonstrated that by employing both rational and transmitted proofs together, the doctrine of tawḥīd is not merely a theological dogma but also a set of principles that can be rationally grounded.