 The enthusiasm for the scientific study of humanity in the period incorporates a tension or paradox concerning the place of humanity in the cosmos, as the cosmos is re-conceived in the context of Enlightenment philosophy and science. Newton’s success early in the Enlightenment of subsuming the phenomena of nature under universal laws of motion, expressed in simple mathematical formulae, encourages the conception of nature as a very complicated machine, whose parts are material and whose motions and properties are fully accounted for by deterministic causal laws. But if our conception of nature is of an exclusively material domain governed by deterministic, mechanical laws, and if we at the same time deny the place of the supernatural in the cosmos, then how does humanity itself fit into the cosmos? On the one hand, the achievements of the natural sciences in general are the great pride of the Enlightenment, manifesting the excellence of distinctively human capacities. The pride and self-assertiveness of humanity in the Enlightenment expresses itself, among other ways, in humanity’s making the study of itself its central concern. On the other hand, the study of humanity in the Enlightenment typically yields a portrait of us that is the opposite of flattering or elevating. Instead of being represented as occupying a privileged place in nature, as made in the image of God, humanity is represented typically in the Enlightenment as a fully natural creature, devoid of free will, of an immortal soul, and of a non-natural faculty of intelligence or reason. The very title of J.O. de La Mettrie’s Man a Machine (1748), for example, seems designed to deflate humanity’s self-conception, and in this respect it is characteristic of the Enlightenment “science of man”. It is true of a number of works of the Enlightenment, perhaps especially works in the more radical French Enlightenment – notable here are Helvétius’s Of the Spirit (1758) and Baron d’Holbach’s System of Nature (1770) – that they at once express the remarkable self-assertiveness of humanity characteristic of the Enlightenment in their scientific aspirations while at the same time painting a portrait of humanity that dramatically deflates its traditional self-image as occupying a privileged position in nature.