Efforts to explain the nature of the lunar spots (or lunar maria) in the premodern Islamic literature were not limited to one field of intellectual inquiry. The issue, rather, falls at the intersection of six major fields: optics, natural philosophy, hay'a (cosmology), kalam (Islamic philosophical theology), Tafsir (Qur'anic exegeses), and hadith (Prophetic Tradition). Writing in each field, different scholars (or sometimes a single scholar), would come up with different hypotheses regarding the nature of the lunar spots. This paper traces these discussions from the tenth to the fourteenth century as presented in the works of Ibn al-Haytham, Ibn Sina, Fakhr al-Din al-Razi, and Qutb al-Din al-Shirazi. I show how the paradigms of the field in which they were writing shaped their understanding of their research problem, affected their choice of criteria for classifying and sifting through the existing hypotheses, and influenced the conception of their own hypothesis. For instance, writing in the field of optics, Ibn al-Haytham considers the lunar spots to be a visually perceived scenery the quiddity of which can be successfully explained through his theory of light. Whereas, Avicenna, who brings up the issue in al-Sama' wa al-'alam of his al-Shifa', sees the lunar spots as a challenge to the simplicity of the celestial bodies (a key principle in his celestial physics) that can be resolved through a physical hypothesis that explains their cause. Moreover, I show that the lunar spots were not always a phenomenon to be explained or a problem to be solved, but sometimes an intellectual tool used by the occasionalist theologians against philosophers.