J. T. MERZ'S LEIBMZ. 441 work to elucidate the principles of Leibniz's thought rather than to attempt the systeniatisation which Leibniz himself did not give. Even if the " English Keader," for whom the volume is expressly intended, has less familiarity with Guhrauer's bio- graphy and with " the well-known historical treatises of Ueber- weg, Kuno Fischer, Erdmann, and Zeller " than the author seems to credit him with, he has much to learn and will be able to learn much from this volume as to the harmony of Leibniz's life and writings, and the principles of which all his work was an application. " Early in life," says the author " Leibniz was actuated by tvo distinct desires in his study of things by the desire to know and think clearly, but not less by the wish to do everything for a purpose and a use. As he rose to the higher aspect and deeper meaning of things, these tendencies became more clearly defined. Clearness and precision of thought meant for him more and more the mathematical and mechanical treatment of scientific problems, while, at the same time, his regard for the practically useful attained a higher significance. It meant that everything in the world had a deeper sense, a meaning, a pin-pose ; that the universe had been created for an end, and that this end was being achieved through the mechanical laws which are the external formula? of the internal essence of things " (p. 69). This passage may be taken as giving the key to Mr. Merz's whole exposition. The Law of Continuity, and his logical prin- ciples of Contradiction and Sufficient Reason, notified Leibniz's adherence to the mechanical view of things (p. 138). But along with this conviction of the necessary connexion of all things by mechanical laws, he held to the permanent individuality of the monad. And it is the connexion of these two points of view that forms one of the greatest difficulties of his philosophy ; and as such receives prominent treatment here. Other difficulties such as that of the relation of God to the monads, or the difficulties caused by Leibniz's expressions regarding the reality of corporeal substance and the relation between body and soul are omitted from the author's plan, perhaps as dealing more with the - -- tematisation of Leibniz's thought than with the principles which guided it. But Leibniz himself never lost sight either of Ms mechanical or of his teleological point of "view ; and it was largely owing to their competing claims that he was forced to formulate definitely his doctrine of pre-established harmony. Yet this doctrine can only serve to explain the consistency of his view of universal inter-connexion with the exclusiveness of the monad, when these two poles of his thought have been already reached independently. Leibniz himself does not seem to have passed from one of them to the other by any logical process. And the author is certainly not far wrong in tracing to a subjective cause the connexion of the two principles in his mind : " Leibniz's love of regularity led him to the mechanical view of nature ; his practical sense, his desire to see a purpose in everything, made