a revolutionary intensification of modern principles, which found comprehensive expression in the atheists' Bible, the _System of Nature_ of Baron Holbach, 1770. The movement begins in the middle of the thirties, when Montesquieu commences to naturalize Locke's political views in France, and Voltaire does the same service for Locke's theory of knowledge, and Newton's natural philosophy, which had already been commended by Maupertuis. The year 1748, the year also of Hume's _Essay_, brings Montesquieu's chief work and La Mettrie's _Man a Machine_. While the _Encyclopedia_, the herald of the Illumination, begun in 1751, is advancing to its completion (1772, or rather 1780), Condillac (1754) and Bonnet (1755) develop theoretical sensationalism, and Helvetius (_On Mind_, 1758; in the same year, D'Alembert's _Elements of Philosophy_) practical sensationalism. Rousseau, engaged in authorship from 1751 and a contributor to the _Encyclopedia_ until 1757 comes into prominence, 1762, with his two chief works, _Emile_ and the _Social Contract_. Parallel with these we find interesting phenomena in the field of political economy: Morelly's communistic _Code of Nature_ (1755), the works of Quesnay (1758), the leader of the physiocrats, and those of Turgot, 1774. Our discussion takes up, first, the introduction and popularization of English ideas; then, the further development of these into a consistent sensationalism, into the morality of interest, and into materialism; finally, the reaction against the illumination of the understanding in Rousseau's philosophy of feeling.[1] [Footnote 1: On the whole chapter cf. Damiron, _Mémoires pour Servir à l'Histoire de la Philosophie au XVIII. Siécle_, 3 vols., 1858-64; and John Morley's _Voltaire_, 1872 [1886], _Rousseau_, 1873 [1886], and _Diderot and the Encyclopedists_, 1878 [new ed., 1886].] 1. %The Entrance of English Doctrines%.