Such was the character of the man, and of the efforts which he directed to the injury of revelation. It has been said(536) that to obliterate his influence from the history of the eighteenth century would be to produce a greater difference than the absence of any other individual in it would occasion; and would be similar to the omission of Luther from the sixteenth. The analogy, though startling, is true in the particulars which it is intended to illustrate. The influence of each was European in his respective century; and the doctrine acted not only on the world of thought, but of action. We have described Voltaire alone; not because he was isolated by any interval of time from a general movement, but because his attack is more rudimentary, being directed rather to disintegrate Christianity than dogmatically to affirm unbelief. He was perhaps rather logically prior to the others than chronologically; being really connected with two bodies of men, which formed the centres of two infidel movements, the one in Paris, the other at the court of Frederick at Berlin. Frederick the Great surrounded himself with French literary men.(537) They were mostly persons who were exiles from France to escape persecution for their opinions, who had first found a refuge in Holland, and thence endeavoured by means of the Dutch booksellers to introduce their writings into France. From about 1740-60 several such teachers of infidelity were invited to the Prussian court, and dispersed their influence in Germany; the effects of which we shall subsequently find. One of them was the physician La Mettrie,(538) who wrote works on physiology marked by a low materialism. Such also was De Prades,(539) and more especially D’Argens.(540) The latter, struck with the force of “the Persian Letters” of Montesquieu, threw his doubts into an epistolary form, “the Jewish Letters;” in which the traditional opinions and ruling systems of the time were attacked with great freedom. He translated also some ancient works to serve his purpose, especially the fragments of the abusive work of the emperor Julian against Christianity, written in favour of the state religion of the Greeks and Romans. While this was the character of some of the Frenchmen at the court of Frederick, whom Voltaire subsequently joined; men who, imbued with the most extravagant form of the philosophy of sensation, verged upon materialism; there were coteries of literary persons in Paris, which were the rallying point of sceptical minds, and centres of irreligious influence.