mathematics, and wrote on many subjects. But he nowhere developed his philosophical views in a systematic and complete form; a mere summary of his doctrines is given in his exposition of the monadology. He adopts the dogmatic form of philosophising, that is, he believed that the power of human thought, when aided by clear and distinct ideas, could transcend the limits of experience, and attain to perfect truth. But he oversteps both the dualism of Descartes, and the monism of Spinoza, by the recognition of a graduated scale of beings. Eternal truths are in the divine understanding, distinct from the divine will; the divine mind being the source of the possibility of things, while the divine will is the cause of their reality; hence all truth must by its nature be rational. In psychology he adopts a form of the doctrine of innate ideas, associated with the principles of identity and contradiction. Error arises from a want of clearness and distinctness; while dark and confused knowledge may be raised by demonstration to clearness and distinct ness. The aim of his theory of monads 29 is to ascertain the existence and to determine the nature of the simplest elements of substance, into which all other things and beings might be resolved. The primary monads seem to be something like atoms, being units of matter and of mind, a kind of points endowed with life and ideas. All the monads have ideas, but of different degrees of clearness. God is the first monad, the primitive substance; and all his ideas are perfect. The souls of animals have sensation and memory. Every soul is a monad, as its power of acting proves its substantiality, and all substances are monads. Inorganic nature is merely an aggregate of undeveloped monads, while plants and minerals are a kind of sleeping monads with unconscious ideas; but in plants these ideas are formative forces. Man is a monad that has been 29 Leibnitz seems to have borrowed the term monads from Bruno; see under p. 423. waked up. The monads are not distinguishable in kind, but only in degree; the difference between them consists in the separate stages of development which each has attained. Every conscious monad has the clearest perception of those parts of the universe to which it is most nearly related; and thus from its own standpoint it is a mirror of the universe. His theory of "pre-established harmony" is thus expressed by himself:-" Every body acts as if there were no soul, and every soul acts as if there were no body; and yet both act as if each was influenced by the other". So between the succession of the ideas, and the motions of the monad, there is a harmony pre-established by God. The soul and body of man agree, as it were, like the two clocks originally set together, and exactly moving at the same rate. In the same way, every part of the universe harmonises with every other part. Creation just consisted in first establishing, once for all, the laws of this unity and harmony; everything being arranged, the parts assigned to their places, every thought and every motion having been foreseen and provided for, when the universe was first called into existence. The existing world, therefore, is the best of all possible worlds, whether our limited minds can understand it in this light or not. The continuity of physical law is never broken, and yet the moral world is in harmony with the physical world, as the course of nature in all cases must be in accord with the highest interest of the soul.30 Though Leibnitz endeavoured to unite the cosmological and the theological ideas, the origin of the world from God, and its explanation by physical laws, he completely failed to establish a real harmony of the two conceptions; as everyone before and after him has failed, in their attempts to unite opposite elements in one conception or principle. The inconsistencies of his philosophy have often been exposed; nevertheless, it is 30 Compare Stewart's Dissert., pp. 254-257, 560-561, ed., 1854; and Ueberweg's Hist. Philos., Vol. II., pp. 106-113. only justice to state that his writings contained many valuable suggestions, which subsequently proved to be true.31 32 Bayle, the author of the Historical and Critical Dictionary, exercised a pretty wide influence on philosophical opinions." He had a sceptical cast of mind, and directed his shafts against all forms of dogmatism, often indulging in sallies of ironical humour. He was a man of considerable erudition, an acute. critic, and endowed with much logical tact and metaphysical subtlety. There are other philosophers whose works I should have deemed it necessary to notice, if I had been writing a complete history of philosophy, such as Malebranche, De la Forge, Sylvain Regis, Arnauld, P. Nicole, Pascal, Du Hamel, Wolf, and others. Turning now to English philosophy, it may be noted that at the present time many in England are conversant with the philosophy of Germany and of France; and the influence of the speculations of both these nations on the English thought of the nineteenth century is probably much greater than is commonly believed. While in the seventeenth and eighteenth centuries, especially in the latter, English philosophy greatly influenced the philosophy of France, and in a less degree that of Germany, in the present century all sides have influenced each other; though it seems that German speculation has recently been in the ascendant in some quarters of England, and even in Scotland. The place of Lord Bacon in the history of philosophy has often been very differently estimated, according to the standpoint of those who have essayed to discuss the point.33 Bacon's avowed aim was to increase the power of man by enlarging the range of his knowledge. But to effect this, the mind must be freed from prejudice and superstition of every sort, so that it 31 For instance, his view of the unconscious modifications of the mind, or latent mental modifications. 32 Born 1647, died 1706. 33 Born 1561, died 1625. may be enabled to apprehend things in their real relations. Knowledge must begin with experience, starting with observation and experiment, whence by induction it should proceed methodically, first to the simpler propositions, and then to others of higher generality, rising gradually step by step to higher universality; and then finally, from these to descend to the particular, and thus to arrive at discoveries which should. extend the power of man over nature. To attain such results he insists strongly on the value and the necessity of a patient collection and accurate comparison of facts. Bacon's plan for the reorganisation of the sciences embraced a general review of the whole intellectual field. This was followed by his doctrine of method, and then by an exposition of the sciences themselves, with their application to new discoveries. His conception was grand, and his end highly laudable; but the development of the principles of his method is far from complete. His own attempts at original investigation in applying his method were often crude, and fall much behind some of the efforts of his own contemporaries. Nevertheless, he succeeded in indicating several of the fundamental points of induction; and thus he became the founder of the empirical school of modern philosophers, though he himself was greater as a critic than as a philosopher. His greatest merit was that he emphatically insisted on the importance of the collection, arrangement and comparison of facts. On the other hand, he undervalued the method of deduction, and the value of the syllogism for deductive and mediate knowledge. His writings have had much influence in Britain, and in other countries of Europe, especially in France; and thus his method of induction has contributed at home and abroad to the progress of physical science.34 The eccentric Lord Herbert of Cherbury was a writer of 34 An excellent account of Bacon and his philosophy is given by Kuno Fischer in a work entitled, "Franz Baco von Verulam, die Real-philosophie und ihr Zeitalter," 1856. some note.35 In his remarkable work, "De Veritate," he treated on various points of mental philosophy. He distinguishes the faculties of the mind into four, namely, natural instinct, the inner sense, the external sense, and the discursive faculty. Each of these powers affords a certain class of truths, and all truth must become known to us through one or other of these faculties. But the truths of natural instinct are relatively higher and more certain than any other. By this faculty (which might have been called intellectual instinct) we apprehend the common notions touching the relations of things, and especially those which tend to our own preservation. They are implanted in us by nature, and represent something of the divine image and wisdom. They are primary notions, since they are necessary, independent, universal, certain, and instantaneous in their manifestation. The inner sense under the direction of natural instinct, or the common notions, embraces all the powers which are associated with the particular forms of the agreeable and the disagreeable, of good and evil, whether these are dependent on the body or on the mind. The chief internal sense is conscience, which judges what is good and evil in their various relations, and thus determines what ought to be done. The external senses depend on the special effects of external objects upon our external organs, jointly with the corresponding internal senses and the natural instincts. The discursive faculty gives that knowledge of objects presented by the internal and external senses, which depends on special capacities for investigation, and on the common notions; and it has reference to existence, qualities, quantities, relations, and especially to their causes. He is also the author of several religious treatises and historical works.36 His views had some influence on the 35 Born 1581, died 1648. but 36 He distinguished man from animals, not merely by the gift of reason, specially by the capacity of religion, which is peculiar to the former. He held |