PHILOSOPHY OF LEIBNITZ Doctrine of Substance.—The central point in the philosophy of Leibnitz was only arrived at after many advances and correc tions in his opinions. This point is his new doctrine of substance (p. and it is through it that unity is given to the succession of occasional writings, scattered over so years, in which he explained his views.
More inclined to agree than to differ with what he read (P. 425), and borrowing from almost every philosophical system, his own standpoint is yet most closely related to that of Descartes, partly as consequence, partly by way of opposition. Cartesianism, Leibnitz often asserted, is the ante-room of truth, but the ante room only. Descartes' separation of things into two heterogeneous substances only connected by the omnipotence of God, and the more logical absorption of both by Spinoza into the one divine substance, followed from an erroneous conception of what the true nature of substance is. Substance, the ultimate reality, can only be conceived as force. Hence Leibnitz's metaphysical view of the monads as simple, percipient, self-active beings, the constituent elements of all things, his physical doctrines of the reality and constancy of force at the same time that space, matter and mo tion are merely phenomenal, and his psychological conception of the continuity and development of consciousness. In the closest connection with the same stand his logical principles of con sistency and sufficient reason, and the method he developed from them, his ethical end of perfection, and his crowning theological conception of the universe as the best possible world, and of God both as its efficient cause and its final harmony.
The ultimate elements of the universe are, according to Leib nitz, individual centres of force or monads. Why they should be individual, and not manifestations of one world-force, he never clearly proves'. His doctrine of individuality seems to have been arrived at, not by strict deduction from the nature of force, but rather from the empirical observation that it is by the manifesta tion of its activity that the separate existence of the individual becomes evident; for his system individuality is as fundamental as activity. "The monads," he says, "are the very atoms of na
ture—in a word, the elements of things," but, as centres of force, they have neither parts, extension nor figure (p. 705). Hence their distinction from the atoms of Democritus and the mate rialists. They are metaphysical points or rather spiritual beings whose very nature it is to act. As the bent bow springs back of itself, so the monads naturally pass and are always passing into action, without any aid but the absence of opposition (p. 122). Nor do they, like the atoms, act upon one another (p. 68o) ; the action of each excludes that of every other. The activity of each is the result of its own past state, the determinator of its own future (pp. 706, 722). "The monads have no windows by which anything may go in or out" (p. 705).
Further, since all substances are of the nature of force, it follows that—"in imitation of the notion which we have of souls" —they must contain something analogous to feeling and appetite. Every monad is a microcosm, the universe in and according to the degree of its activity is the distinctness of its representa tion of the universe (p. 709). By the proportion of activity to passivity in it one monad is differentiated from another. There is neither vacuum nor break in nature, but "everything takes place by degrees" (p. 392), the different species of creatures rising by insensible steps from the lowest to the most perfect form (p. 312).
As in every monad each succeeding state is the consequence of the preceding, and as it is of the nature of every monad to mirror or represent the universe, it follows (p. 774) that the perceptive 'When not otherwise stated, the references are to Erdmann's edition of the Opera philosophica.