Cicero’s De natura deorum, De divinatione, De fato, and Timaeus offer a coherent development of some of the questions first raised in De republica and De legibus. In the specific context of the mid-first-century bce debate between Stoics and Epicureans, Cicero raises three far-reaching issues: can a rational discourse on religion be developed without a solid cosmological and theological foundation? What use can be made of historical and anthropological observations of cultual practices? Is it possible to reach a universal definition of the psychological process which accounts for human attitudes towards the gods? Cicero’s authorial strategies frame skeptical arguments so as to suggest constructive answers and preserve human freedom and moral responsibility. A mythopoetical discourse on the universe offers sufficient background as “provisional physics.” Historical enquiries help define precise limits for political thinking on religion. Philosophy explains psychologically how the admiration for the beauty of the world leads to ethical accomplishment.