VOLTAIRE.--One of the most notorious names associated with the type of propaganda referred to is that of Voltaire (1694-1778). Voltaire's polemic cannot be described as anti-religious, for he himself was a theist. It was, rather, political in character. The object of his attack was the Catholic Church as existing in France in his day, which he regarded as the chief surviving obstacle to human progress. _Ecrasez l'infame_ was his motto; and if this seems a trifle fanatical, let us not forget, as an acute critic has observed, "that what Catholicism was accomplishing in France in the first half of the eighteenth century was not anything less momentous than the slow strangling of French civilisation."[18] Voltaire was an industrious and prolific writer (his works are numbered by scores), but he was also a master of French prose, and he was universally read. From the point of view of the history of European thought his importance lies in his popularisation in France of the Newtonian physics.[19] _Newtonisme_ was a word coined by him, and became associated with a mechanical view of nature. He also conducted a vigorous polemic against certain religious notions, then current, but now out-of-date, and which need not here detain us. Voltaire was an anti-clerical, but he was not hostile to religion; he was chiefly regarded as an exponent of English (i.e. progressive) ideas. LA METTRIE.--An advance in the materialistic direction was taken, however, by La Mettrie (1709-1751), who approached the problem from the side of physiology (he was a physician by profession). His two important contributions were _Histoire naturelle de l'ame_ (1745), and _L'Homme Machine_ (1748). The titles are sufficient to indicate the scope of these works. That of the latter points back to Descartes, who had applied the mechanical theory to animals only, and not to man. La Mettrie extended his application to include man. The implications of this theory did not escape La Mettrie's contemporaries. DIDEROT AND HIS ENCYCLOPAEDIA.--A definite period in the history of thought is certainly marked by the successful attempt on the part of a group of progressive thinkers, to extend the circle open to scientific ideas by the publication of an Encyclopaedia which should contain all the latest knowledge and speculation. The credit for this notable performance was due to Diderot, who in spite of immense difficulties, which were aggravated by the ecclesiastical authorities and the supporters of reaction in general, carried the work through to a triumphant conclusion. The first volume appeared in 1751. The work was composed with an eye to current prejudices; the language was guarded, but the anti-clerical tendency of the whole was by no means obscure. Diderot, however, did not obtrude in the Encyclopaedia the definitely anti-religious opinions which he had developed and which are revealed in his correspondence.