We see still further what it means when we learn that it is by this conception that Leibniz reconciles the conceptions of physical and final causation. There is no principle closer to the thought of Leibniz than that of the equal presence and efficiency everywhere of both physical and final causes. Every fact which occurs is susceptible of a mechanical and of a rational explanation. It is necessarily connected with preceding states, and it has a necessary end which it is fulfilling. The complete meaning of this principle will meet us hereafter; at present we must notice that it is one form of the doctrine of pre-established harmony. All things have an end because they form parts of one system; everything that occurs looks forward to something else and prepares the way for it, and yet it is itself mechanically conditioned by its antecedents. This is only another way of saying that there is complete harmony between all beings in the universe; so that each monad in fulfilling the law of its own existence contributes to the immanent significance of the universe. The monads are co-ordinated in such a way that they express a common idea. There is a plan common to all, in which each has its own place. All are making towards one goal, expressing one purpose. The universe is an organism; and Leibniz would have applied to it the words which Milne-Edwards applied to the human organism, as I find them quoted by Lewes: "In the organism everything seems to be calculated with one determined result in view; and the harmony of the parts does not result from the influence which they exert upon one another, but from their co-ordination under the rule of a common force, a preconceived plan, a pre-existent force." That is to say, the universe is teleological, both as a whole and in its parts; for there is a common idea animating it and expressed by it; it is mechanical, for this idea is realized and manifested by the outworking of forces. It ought to be evident even from this imperfect sketch that the Leibnizian theory of pre-established harmony is not that utterly artificial and grotesque doctrine which it is sometimes represented to be. The phrase "pre-established harmony" is, strictly speaking, tautologous. The term "pre-established" is superfluous. It means "existent." There is no real harmony which is not existent or pre-established. An accidental harmony is a contradiction in terms. It means a chaotic cosmos, an unordered order, a lawless law, or whatever else is nonsensical.