Kant’s cosmological writings from the mid-1750s to mid-1760s have important implications for Kant’s concept of autonomy. A fuller understanding of Kant’s early cosmological resolution of the tension between a new mathematical science and traditional notions moral culpability and divine power sheds unexpected light upon certain underlying issues that framed his reception of the British Moralists and – above all, Rousseau –issues that continued to preoccupy Kant in the years leading up to and beyond his presentation of the principle of autonomy as the “supreme principle of morality” in the mid-1780s. And it gives rise to a number of doctrines, including the formula of universality, and the priority of morality to religion, that would remain virtually unchanged in his later writings. Kant’s cosmological experiments before and after reading Rousseau suggest that that a “political” conception of worldly interaction centered on laws of freedom may have captured Kant’s attention earlier than is generally recognized.