Philosophical arguments for and against the existence of God have been crucial to Euro-American and South Asian philosophers for over a millennium. Critical to the history of philosophy in India, were the centuries-long arguments between Buddhist and Hindu philosophers about the existence of a God-like being called Isvara and the religious epistemology used to support them. By focusing on the work of Ratnakirti, one of the last great Buddhist philosophers of India, and his arguments against his Hindu opponents, Parimal G. Patil illuminates South Asian intellectual practices and the nature of philosophy during the final phase of Buddhism in India. Based at the famous university of Vikramasila, Ratnakirti brought the full range of Buddhist philosophical resources to bear on his critique of his Hindu opponents' cosmological/design argument. At stake in his critique was nothing less than the nature of inferential reasoning, the metaphysics of epistemology, and the relevance of philosophy to the practice of religion. In developing a proper comparative approach to the philosophy of religion, Patil transcends the disciplinary boundaries of religious studies, philosophy, and South Asian studies and applies the remarkable work of philosophers like Ratnakirti to contemporary issues in philosophy and religion.