“The earth in the sky is like the yolk of the egg in the egg white”: Natural Philosophy in the Polemics of the Muslims of Medieval Iberia


Imaginary debate between Averroes and Porphyry of Tyre  (234-305 CE), Monfredo de Monte Imperialis, Liber de herbis (14th c.) . (Public domain, wikimedia commons).




Mònica Colominas Aparicio


This project investigates natural philosophy in the religious polemics of the medieval Muslims of the Iberian Peninsula subjected to Christian rule, the Mudejars. It discusses the role of this science within the processes of identity construction and transmission of knowledge of the Mudejars in competition with the Christian majority and the other important religious minority in the Christian territories of the Iberian Peninsula, the Jews.


Recent scholarship has demonstrated that epistemological frameworks – among which that of philosophy – and of identity in the Iberian Peninsula need to be explained through the complex networks of interaction between Christians, Muslims and Jews.


The present investigation builds on this perspective and aims to explore how the main outlines of the Mudejars’ natural philosophy intertwine with and depart from the conceptualizations of the Christians and the Jews on the same issues. It discusses both the challenges faced by those who claimed that revelation had to be proven by ‘rationalist’ or philosophical evidence and the possibilities that the defense of an Islamic cosmology that was articulated in natural-philosophical terms offered to the interreligious debate in the later Middle Ages.


One of my main sources is the fourteenth-century Mudejar polemic of Kitāb al-Mujādala maʿa -l-Yahūd wa’l-Naṣārā [‘The Book of Disputation with the Jews and the Christians’]. This treatise against the Christians and the Jews strongly relies on Ibn Rushd’s philosophy and Aristotle’s Falsafa at-Tabīʿiyya [‘Natural Philosophy’]. Previous analysis has highlighted the exceptionality of Kitāb al-Mujādala in the polemical literature of the Mudejars and the need for a better understanding of the author’s considerations regarding the epistemological status of philosophy in the study of Islam. Furthermore, polemics are most important sources for the study of the interreligious debate and the convivencia in the Iberian Peninsula.