The Coherence of the Astronomers: Incomplete Knowledge and Imaginative Exploration in the Marāgha Tradition of Islamic Astronomy

This thesis explores ideas about the limits, prerequisites, and objectives of investigating nature, primarily but not exclusively through astronomy, at work in the writings of Islamic scholars including Ibn al-Haytham, al-Ghazālī, and several astronomers of the Marāgha tradition. The latter tradition of modified Ptolemaic astronomy answered both Ibn al-Haytham's call for conceptual and predictive consistency and al-Ghazālī's for metaphysical hesitancy appropriate to human reason's limitations. Virtuosity and rhetoric, spirituality and one-upmanship, and perhaps even artistry evident in the Marāgha astronomers' proliferation of ingenious models highlight an elective quality that bridges the 'motivation gap' between their ongoing model-making and the lack of more tangible motivations, revealing the humanity behind their enterprise. Al-Ghazālī, once thought a destroyer of Islamic science and philosophy, truly helped give shape to a distinct and distinctive style of astronomy as an exploration of God, the heavens, and the bounds of human knowledge.