A daring account of the philosophical development of the idea of a rational society and its consequences for the present In the seventeenth century, a vision arose which was to captivate the Western imagination for the next three hundred years: the vision of Cosmopolis, a society as rationally ordered as the Newtonian view of nature. While fueling extraordinary advances in all fields of human endeavor, this vision perpetuated a hidden yet persistent agenda: the delusion that human nature and society could be fitted into precise and manageable rational categories. Stephen Toulmin confronts that agenda--its illusions and its consequences for our present and future world.