Gottfried Wilhelm Leibnitz was born in 1646 at Leipsic, where his father (Friederich Leibnitz, died 1652) was professor of moral philosophy; in his fifteenth year he entered the university of his native city, with law as his principal subject. Besides law, he devoted himself with quite as much of ardor to philosophy under Jacob Thomasius (died 1684, the father of Christian Thomasius), and to mathematics under E. Weigel in Jena. In 1663 (with a dissertation entitled De Principio Individui) he became Bachelor, in 1664 Master of Philosophy, and in 1666, at Altdorf, Doctor of Laws, and then declined the professorship extraordinary offered him in the latter place. Having made the acquaintance of the former minister of the Elector of Mayence, Freiherr von Boineburg, in Nuremberg, he went, after a short stay at Frankfort-on-the-Main, to the court of the Elector at Mayence, at whose request he devoted himself to the reform of legal procedure, besides writing, while there, on the most diverse subjects. In 1672 he went to Paris, where he remained during four years with the exception of a short stay in London. The special purpose of the journey to Paris—to persuade Louis XIV to undertake a campaign in Egypt, in order to divert him from his designs upon Germany—was not successful; but Leibnitz was captivated by the society of the Parisian scholars, among them the mathematician, Huygens. From the end of 1676 until his death in 1716 Leibnitz lived in Hanover, whither he had been called by Johann Friedrich, as court councillor and librarian. The successor of this prince, Ernst August, who, with his wife Sophie, and his daughter Sophie Charlotte, showed great kindness to the philosopher, wished him to write a history of the princely house of Brunswick; and a journey which he made in order to study for this purpose was extended as far as Vienna and Rome. Upon his return he took charge of the Wolfenbüttel library in addition to his other engagements.
The marriage of the Princess Sophie Charlotte with Frederick of Brandenburg, the first king of Prussia, brought Leibnitz into close relations with Berlin. At his suggestion the Academy (Society) of Sciences was founded there in 1700, and he himself became its first president. In Charlottenburg he worked on his principal work, the New Essays concerning the Human Understanding, which was aimed at Locke, but the publication of which was deferred on account of the death of the latter in the interim (1704), and did not take place until 1765, in Raspe's collective edition. The death of the Prussian queen in 1705 interrupted for several years the Theodicy, which had been undertaken at her request, and which did not appear until 1710. In Vienna, where he resided in 1713-14, Leibnitz composed a short statement of his system for Prince Eugen; this, according to Gerhardt, was not the sketch in ninety paragraphs, familiar under the title Monadology, which was first published in the original by J.E. Erdmann in his excellent Complete Edition of the Philosophical Works of Leibnitz, 1840, but the Principles of Nature and of Grace, which appeared two years after the author's death in L'Europe Savante. While Ernst August, as well as the German emperor and Peter the Great, distinguished the philosopher, who was not indifferent to such honors, by the bestowal of titles and preferments, his relations with the Hanoverian court, which until then had been so cordial, grew cold after the Elector Georg Ludwig ascended the English throne as George I. The letters which Leibnitz interchanged with his daughter-in-law, gave rise to the correspondence, continued to his death, with Clarke, who defended the theology of Newton against him. The contest for priority between Leibnitz and Newton concerning the invention of the differential calculus was later settled by the decision that Newton invented his method of fluxions first, but that Leibnitz published his differential calculus earlier and in a more perfect form. The variety of pursuits in which Leibnitz was engaged was unfavorable to the development and influence of his philosophy, in that it hindered him from working out his original ideas in systematic form, and left him leisure only for the composition of shorter essays. Besides the two larger works mentioned above, the New Essays and the Theodicy, we have of philosophical works by Leibnitz only a series of private letters, and articles for the scientific journals (the Journal des Savants in Paris, and the Acta Eruditorum in Leipsic, etc.), among which may be mentioned as specially important the New System of Nature, and of the Interaction of Substances as well as of the Union which exists between the Soul and the Body, 1695, which was followed during the next year by three explanations of it, and the paper De Ipsa Natura, 1698. Previous to Erdmann (1840) the following had deserved credit for their editions of Leibnitz: Feller, Kortholt, Gruber, Raspe, Dutens, Feder, Guhrauer (the German works), and since Erdmann, Pertz, Foucher de Careil, Onno Klopp, and especially J.C. Gerhardt. The last named published the mathematical works in seven volumes in 1849-63, and recently, Berlin, 1875-90, the philosophical treatises, also in seven volumes.[1] In our account of the philosophy of Leibnitz we begin with the fundamental metaphysical concepts, pass next to his theory of living beings and of man (theory of knowledge and ethics), and close with his inquiries into the philosophy of religion.
[Footnote 1: We have a life of Leibnitz by G.E. Guhrauer, jubilee edition, Breslau, 1846 [Mackie's Life, Boston, 1845 is based on Guhrauer]. Among recent works on Leibnitz, we note the little work by Merz, Blackwood's Philosophical Classics, 1884, and Ludwig Stein's Leibniz und Spinoza, Berlin, 1890, in which with the aid of previously unedited material the relations of Leibnitz to Spinoza (whom he visited at The Hague on his return journey from Paris) are discussed, and the attempt is made to trace the development of the theory of monads, down to 1697. The new exposition of the Leibnitzian monadology by Ed. Dillman, which has just appeared, we have not yet been able to examine [The English reader may be referred further to Dewey's Leibniz in Griggs's Philosophical Classics, 1888, and Duncan's Philosophical Works of Leibnitz (selections translated, with notes), New Haven, 1890, as well as to the work of Merz already mentioned.—TR.]
%1. Metaphysics: the Monads, Representation, the Pre-established Harmony; the Laws of Thought and of the World.%
Leibnitz develops his new concept of substance, the monad,[1] in conjunction with, yet in opposition to, the Cartesian and the atomistic conceptions. The Cartesians are right when they make the concept of substance the cardinal point in metaphysics and explain it by the concept of independence. But they are wrong in their further definition of this second concept. If we take independence in the sense of unlimitedness and aseity, we can speak, as the example of Spinoza shows, of only one, the divine substance. If the Spinozistic result is to be avoided, we must substitute independent action for independent existence, self-activity for self-existence. Substance is not that which exists through itself (otherwise there would be no finite substances), but that which acts through itself, or that which contains in itself the ground of its changing states. Substance is to be defined by active force,[2] by which we mean something different from and better than the bare possibility or capacity of the Scholastics. The potentia sive facultas, in order to issue into action, requires positive stimulation from without, while the vis activa (like an elastic body) sets itself in motion whenever no external hindrance opposes. Substance is a being capable of action (la substance est un être capable d'action). With the equation of activity and existence (quod non agit, non existit) the substantiality which Spinoza had taken away from individual things is restored to them: they are active, consequently, in spite of their limitedness, substantial beings (quod agit, est substantia singularis). Because of its inner activity every existing thing is a determinate individual, and different from every other being. Substance is an individual being endowed with force.
[Footnote 1: According to L. Stein's conjecture, Leibnitz took the expression Monad, which he employs after 1696, from the younger (Franc. Mercurius) van Helmont.]
[Footnote 2: Francis Glisson (1596-1677, professor of medicine in Cambridge and London) had as early as 1671, conceived substances as forces in his treatise De Natura Substantiae Energetica. That Glisson influenced Leibnitz, as maintained by H. Marion (Paris, 1880), has not been proven; cf. L. Stein, p. 184.]
The atomists are right when they postulate for the explanation of phenomenal bodies simple, indivisible, eternal units, for every composite consists of simple parts. But they are wrong when they regard these invisible, minute corpuscles, which are intended to subserve this purpose as indivisible: everything that is material, however small it be, is divisible to infinity, nay, is in fact endlessly divided. If we are to find indivisible units, we must pass over into the realm of the immaterial and come to the conclusion that bodies are composed of immaterial constituents. Physical points, the atoms, are physical, but not points; mathematical points are indivisible, but not real; metaphysical or substantial points, the incorporeal, soul-like units, alone combine in themselves indivisibility and reality—the monads are the true atoms. Together with indivisibility they possess immortality; as it is impossible for them to arise and perish through the combination and separation of parts, they cannot come into being or pass out of it in any natural way whatever, but only by creation or annihilation. Their non-spatial or punctual character implies the impossibility of all external influence, the monad develops its states from its own inner nature, has need of no other thing, is sufficient unto itself, and therefore deserves the Aristotelian name, entelechy.
Thus two lines of thought combine in the concept of the monad. Gratefully recognizing the suggestions from both sides, Leibnitz called Cartesianism the antechamber of the true philosophy, and atomism the preparation for the theory of monads. From the first it followed that the substances were self-acting forces; from the second, that they were immaterial units. Through the combination of both determinations we gain information concerning the kind of force or activity which constitutes the being of the monad: the monads are representative forces. There is nothing truly real in the world save the monads and their representations [ideas, perceptions].
In discussing the representation in which the being and activity of the monads consist, we must not think directly of the conscious activity of the human soul. Representation has in Leibnitz a wider meaning than that usually associated with the word. The distinction, which has become of the first importance for psychology, between mere representation and conscious representation, or between perception and apperception, may be best explained by the example of the sound of the waves. The roar which we perceive in the vicinity of the sea-beach is composed of the numerous sounds of the single waves. Each single sound is of itself too small to be heard; nevertheless it must make an impression on us, if only a small one, since otherwise their total—as a sum of mere nothings—could not be heard. The sensation which the motion of the single wave causes is a weak, confused, unconscious, infinitesimal perception (petite, insensible perception), which must be combined with many similar minute sensations in order to become strong and distinct, or to rise above the threshold of consciousness. The sound of the single wave is felt, but not distinguished, is perceived, but not apperceived. These obscure states of unconscious representation, which are present in the mind of man along with states of clear consciousness, make up, in the lowest grade of existence, the whole life of the monad. There are beings which never rise above the condition of deep sleep or stupor.