Chapter 4 discusses the circle that formed around the intelligencer Samuel Hartlib (1600–1662). Its overarching argument is that utilitarian science offered guidance in finding the simplicity of the unum necessarium (Luke 10:42), a common theme exalted by contemporary Millenarianism of the Protestant cause. In practical terms, knowledge about necessities became the means to achieving that goal of faith. The scepticism of the period and its obvious corrupting effects on morality and devotion led to inventiveness in pursuit of substitutes for the classical moral principle of the light of reason. The Reformers worked towards a political and theological project of a utilitarian science as a means by which to reach God and reproduce Paradise on earth. Scientific knowledge about trade became central and was expressed, significantly, in the momentous Navigation Acts of 1651.