Astronomy occupies a distinctive place in the intellectual tradition of the Islamic world. In particular, the historic mathematics and astronomy schools of Maragha and Samarkand played a pivotal role in the development of Islamic thought. During this period, significant transformations occurred in the way the relationship between astronomy and metaphysics was understood. At the same time, astronomy had acquired such a strong institutional foundation and intellectual authority within the Islamic scholarly tradition that it could no longer be ignored. Consequently, although theologians objected to the metaphysical interpretations advanced by astronomers, they could not reject the computational power and practical utility of astronomy altogether.
In other words, regardless of whether astronomy was regarded as a discipline capable of making ontological claims about reality, it was increasingly acknowledged as a mathematical science that successfully described and predicted celestial phenomena. Therefore, understanding the various approaches developed to define the relationship between astronomy, physics and metaphysics, as well as tracing how these approaches evolved over time, is of considerable importance. In this column, these intellectual approaches and the major turning points in their development will be examined on the basis of F. Jamil Ragep's article, "Freeing Astronomy from Philosophy: An Aspect of Islamic Influence on Science."
Ragep first highlights a fundamental aspect of astronomy's status in the Islamic world: astronomy developed not only as a theoretical field of knowledge but also as a discipline that addressed the practical needs of religious life. Determining the times of daily prayers, establishing the direction of the qibla, calculating the beginning of Ramadan, and regulating the calendar all provided astronomy with strong social legitimacy. As a result, astronomy ceased to be a field of interest confined to philosophers or court circles and instead gained broad institutional support, extending from mosques to madrassas. This institutional foundation enabled astronomers not only to meet the practical requirements of religious life but also to pursue new avenues of research in observation, computation and mathematical modeling. Moreover, for many astronomers, the study of the heavens was not merely a technical endeavor but also a means of appreciating the order and wisdom embedded in God's creation. Consequently, astronomy came to occupy a privileged position in the Islamic intellectual tradition, distinguished by both its practical significance and its intellectual prestige.
The first significant intervention concerning the place of astronomy within the Islamic intellectual tradition came from Ibn Sina, commonly known in the West as Avicenna. According to Ragep, Ibn Sina's principal contribution was to distinguish astronomy from astrology through a systematic classification of the sciences. This distinction preserved astronomy as a legitimate field of knowledge grounded in observation and mathematical demonstration while simultaneously freeing it from some of the more contentious burdens associated with physics and metaphysics. Nevertheless, Ibn Sina continued to uphold Aristotelian cosmology and natural philosophy. In other words, although astronomy had been emancipated from astrology, it remained firmly embedded within the Aristotelian conception of the universe.
Historically, the second stage was marked by the contributions of al-Ghazali and, later, Adud al-Din al-Iji, who developed a different approach to this relationship. As Ragep points out, they acknowledged the computational power and practical value of astronomy while restricting its authority to make metaphysical claims. In doing so, they granted astronomy a limited form of legitimacy; however, this legitimacy was essentially instrumental, since they denied it the authority to draw metaphysical conclusions. According to this perspective, astronomy could perform calculations and accurately describe celestial phenomena, but it could not determine the ultimate nature of reality. In other words, astronomy was assigned an epistemological function without being granted ontological authority. Nasir al-Din al-Tusi, the founder of the Maragha School of Astronomy, occupied a more complex position. On the one hand, he sought to establish astronomy on as rigorous a mathematical foundation as possible; on the other hand, he continued to rely on Aristotelian natural philosophy in certain critical matters, most notably in defending the immobility of the Earth.
As Ragep emphasizes in his article, the intervention of Sayyid Sharif al-Jurjani established an entirely different framework and represented a decisive intellectual turning point. Al-Jurjani argued that astronomical models were not merely computational devices. Nor were they purely arbitrary constructions; rather, they corresponded to "nafs al-amr" – the actual state of affairs or objective reality. Within the epistemological tradition, this concept signifies that knowledge is not merely a collection of mental representations but refers to an order of truth that exists independently of the human mind. According to al-Jurjani, it is precisely this correspondence that gives astronomical models their epistemic value. His critique, therefore, was fundamentally epistemological in nature. Whereas the instrumentalism of al-Ghazali and al-Iji regarded astronomical models simply as useful computational tools, al-Jurjani maintained that their explanatory and predictive success stemmed from their correspondence, however partial, with the underlying structure of reality. If celestial models were nothing more than convenient fictions, they could neither generate such remarkably accurate predictions about the universe nor reveal the order embedded in creation.
From this perspective, al-Jurjani's intervention significantly relaxed the boundary established by al-Ghazali and al-Iji. By relating astronomical models to "nafs al-amr," he argued that astronomers were not merely performing calculations but were also producing genuine knowledge about reality. Consequently, al-Jurjani's contribution effectively dissolved the restriction imposed by al-Ghazali and al-Iji, restoring astronomy's status as a discipline capable of making meaningful claims about the nature of reality.
Up to this point, the article makes it clear that the central tension lies not between religion and astronomy, but rather in the question of what kind of knowledge astronomy itself represents. Is astronomy merely a technical discipline that produces successful calculations, or is it a science capable of uncovering the true structure of the universe? Al-Jurjani's answer is unequivocally the latter. In his view, astronomy is capable of attaining genuine knowledge of reality through its own methods. Moreover, by establishing a connection between astronomy and "nafs al-amr," al-Jurjani provides an epistemological foundation for the ontological significance of the conclusions reached through astronomical inquiry. In doing so, he also liberates astronomy from its dependence on metaphysics.
According to Ragep's interpretation, the decisive turning point comes with Ali Qushji. His significance lies in accomplishing two important intellectual moves simultaneously. First, like al-Jurjani, he accepted that astronomy possesses genuine truth value. He did not regard astronomy merely as a computational technique; rather, he viewed it as one of the means through which the order and wisdom of God's creation could be understood. Second, departing from al-Tusi, he rejected the view that astronomy must remain dependent upon Aristotelian physics and metaphysics. While preserving astronomy's epistemic and ontological significance, he emancipated it from the framework of Aristotelian natural philosophy and metaphysics. As Turkish scholar Ihsan Fazlıoğlu aptly summarizes: "Ali Qushji's proposal may be summarized, within the specific context of the science of astronomy (ilm al-hay'a), as the abandonment of Avicennan philosophical principles – regarded as defective – as well as Aristotelian physics and metaphysics, in favor of establishing a new physics grounded in sense perception, intuition (ḥads), and mathematics as the proper means of producing reliable knowledge about nature."
More importantly, as Ragep emphasizes, Ali Qushji achieved this intellectual emancipation not out of an anti-religious impulse but, paradoxically, by taking the "Ash'arite" (a school of theology in Sunni Islam) conception of causality seriously. If natural causation is not necessary in itself, then astronomy need not remain bound to Aristotelian physics. Thus, religious objections, paradoxically, came to serve as a force that liberated astronomy from philosophy. Within the broader narrative developed in the article, Ali Qushji represents the culmination of the intellectual transformation that began with Ibn Sina and continued through al-Ghazali, al-Iji, al-Tusi and al-Jurjani. If Ibn Sina freed astronomy from astrology, then Ali Qushji freed it from its dependence on Aristotelian physics and metaphysics. From the perspective advanced in the article, therefore, Ali Qushji's historical significance lies not merely in his contribution to the Ottoman astronomical tradition, but in his pioneering effort to redefine astronomy as an autonomous scientific discipline.
