and had personal conferences on the subject with Peter the Great. He busied himself with the progress of education and missions in Russia, and also in the German states, where he was anxious that the schools and colleges should be seminaries of protestant missions. A great part of his time, especially in the latter years of his life, was devoted to civil and ecclesiastical negotiations, and especially to projects for restoring the unity of the Western church, and failing that for organizing the protestant communions on a common basis. These schemes of ecclesiastical eclecticism were congenial to his comprehensive genius, which, like that of Grotius and many other kindred spirits, found gratification in the unity of the catholic church, with its ritual and organization, apparently so suited to all the various characters and circumstances of those whom it designs to embrace within its ample fold. Political considerations at the same time powerfully influenced Leibnitz in his theories of a united church. At an earlier period of his life, the reunion of the protestants with the Church of Rome was placed by him in the first rank of those questions on a settlement of which his heart was set. It produced a large correspondence with the landgrave of Hesse Rheinfels, with Arnauld, with Spinoza, and with Bossuet, and occupied more or less of his time during twenty years. His love for scholastic learning may have influenced him favourably towards the Roman church. Though he firmly resisted all solicitations to join its outward communion, yet his heart and perhaps his conviction was accorded to the system of the hierarchy, and he has been claimed by the catholics as a member of their communion at his death. His veneration for the Romish theory of a living infallible authority, supplementary to and expository of the written word of scripture, was indeed coupled with a protest against the existing corruptions of the church, and an expression of fear that a formal adherence to Rome might, from the social intolerance of the Romish theologians, cramp the freedom of his philosophical speculations. During the later years of his life he was engaged in another project of ecclesiastical union. About 1697, he promoted a plan, encouraged by the courts of Hanover and Berlin, for a general union of protestants against Rome, and especially of the two great sections of protestantism—the Lutheran and the Reformed. These negotiations, in which Jablonski, Molanus, and others took part, gradually proved abortive, and in a few years Leibnitz abandoned his effort. They were followed by negotiations for a union of the churches of Germany and England, and for the introduction of the Anglican liturgy into Prussia and Hanover. But after a long correspondence nothing was brought to pass, there being no desire in Germany to change the existing forms of church government and worship. The relative doctrine of toleration, and the social laws which regulate the attainment of truth, were frequently the subjects of speculation on the part of Leibnitz. His disposition was naturally tolerant. In his writings we have occasional suggestions of those doctrines which are now widely professed, and which in that age were powerfully enforced by Bayle and Locke.
Leibnitz was able in an unusual degree to unite the practical and the purely speculative life. But amid his varied political and ecclesiastical projects, and his marvellous literary activity, the metaphysical tendency always retained its ascendancy in his mind. His philosophical principles were gradually matured after his settlement in Hanover in 1676, and were given to the world from time to time in a fragmentary form, through reviews, letters, and occasional tracts. Many of these remained unpublished in the royal library at Hanover until long after his death, and his most recent editors are still drawing largely upon the immense stores which his MSS. supply. He has produced no single work which contains a systematic exposition and defence of his philosophical creed. His "Meditationes de Cognitione, Veritate, et Ideis," which contain his famous distinction of intuitive and symbolical knowledge, and his exposition of the logical degrees of conception, appeared in 1684, in the Acta Eruditorum of Leipsic His system of pre-established harmony is referred to in a letter to Arnauld in 1690, and more fully expounded in his tract, entitled "Systeme Nouveau de la Nature," published in the Journal de Savans for June, 1695, as well as in other articles or letters in that journal in the following year. His theory of monads, indicated in his earlier fragments on substance and cause, as well as in his criticisms of Des Cartes and Malebranche, and which pervades his later philosophical works, is expounded in "La Monadologie," written in 1714, and recently published from the Hanover manuscripts. The "Theodicée," published in 1710, when Leibnitz was in his sixty-fourth year, is the most generally known, and, except the "Nouveaux Essais," the largest of all his philosophical works. It holds a foremost place among works on the philosophy of theology. Its avowed purpose is to refute the scepticism of Bayle, who disputed the consistency of faith and reason, and it was perhaps indirectly suggested by the life-long efforts of Leibnitz to restore the unity of Christendom. The design of the "Theodicée" is, by a scheme of optimism, to reconcile the existence and continuance of evil in the universe with the moral government of God—to meet the difficulty common to all religions—the fundamental metaphysical problem of christianity. The subject had been pondered by Leibnitz for many years. In 1671 he wrote a tract on free will and predestination, which was circulated in manuscript among the German theologians. The "Theodicée" was at last published, at the instigation of the philosophical queen of Prussia, a pupil of Leibnitz, and to whom he was in the habit of reading and explaining the writings of Bayle. After a preliminary "Discours de la Conformité de la Foi avec Raison," the "Theodicée" is divided into three parts, in which the author treats "Sur la bonté de Dieu, la liberté de l'homme, et l'origine du mal." The whole is followed by a synopsis of the reasoning, a criticism of Hobbes on Necessity, and of Archbishop King's De Origine Mali, and by a series of aphorisms entitled "Causa Dei asserta per justitiam ejus cum cæteris ejus perfectionibus cunctisque actionibus conciliatam." In 1714 he wrote a tract entitled "Principes de la Nature et de la Grace, fondés en Raison." To the same period belongs his philosophical correspondence with Des Bosses, Bourguet, and De Montmort. The close of 1715 is remarkable as the commencement of a more interesting correspondence than any of these. In a letter to the princess of Wales, Leibnitz criticized the philosophical and theological principles of the English school of Locke and Newton. This called forth Samuel Clarke in their defence. The replies of Leibnitz and the rejoinders of Clarke contain as large an amount of curious metaphysical discussion as any work of modern times. The manner of God's relation to the universe and to man, the meaning of a miracle, the ideas of space and time, and the nature and limits of the material world, are among the stores of this philosophical magazine. An edition of the "Correspondence," in French and English, was published in London in 1717, with an appendix which contains Clarke's Reply to the Inquiry concerning Human Liberty, of Anthony Collins. Inferior in originality and comprehensiveness to his rival, the acute logical intellect of Clarke rendered him a formidable antagonist, and demanded a full display of the intellectual grandeur of his German rival. But that mighty spirit was now to pass away. Leibnitz had suffered from occasional periods of ill health for several years. In November, 1716, when he had to prepare his reply to Clarke's fifth letter, and was still busied with his "Annals of the House of Brunswick," of which the first volume had appeared in the preceding year, and when he was contemplating a comprehensive exposition of his entire system of philosophy, he was suddenly overtaken by death. During the last day of his life, we are told, he conversed with his physician on the scientific nature of his disease, and on the doctrines of alchemy. Towards evening his servant asked if he would receive the Eucharist. "Let me alone," he said, "I have done ill to none. All must die." He raised himself on the bed and tried to write. The darkness of death was gathering round him. He failed to read what he had written, and lying down, covered his face with his hands. In a few minutes he ceased to breathe, on the evening of the 14th November, 1716.
Towards the close of his life Leibnitz lost the favour of his royal master whom he had served so well, and in his last years he looked for a home, at one time in the splendid metropolis of France, and again in London or Vienna. But he lived to the last in Hanover, and in the court church of that city his remains repose, long left by the indifference of his countrymen without any memorial, though a copper plate in one of the aisles, bearing the inscription "Ossa Leibnitii," now marks the spot. In later times, however, Germany has returned with reverential regard to her most illustrious intellectual son. Twenty years ago his philosophical works were collected and edited by Erdmann; and more than one edition of his complete works, many of them now in course of publication for the first time, is in progress. The "Nouveaux Essais sur
