CHAPTER V

THE RATIONALISM OF THE NATURAL SCIENCE PERIOD OF THE RENAISSANCE

=The Nature of Rationalism.= Although the new science grew apace, it was not altogether a safe vocation. Natural science involves metaphysical questions at every point. The scientist at this time, therefore, found himself often in delicate relations with the jealous church guardians. A scientific explanation of the universe might antagonize the church dogma concerning God, creation, and the final outcome of the world. The church doctrine concerning the soul, too, its nature and its immortality, its relation to the body, might be antagonized by physiological and psychological discussions. In such dilemmas as these the natural scientist was not successful in pretending to isolate himself entirely from theology and in assuming an attitude of aloofness to it. Galileo might declare that, whatever the results of his investigations in physics might be, they had nothing to do with the Bible; but he sorrowfully found that the Inquisition thought otherwise. Copernicus found that his astronomical theories came into conflict with church dogma, and he was tormented by his bishop. Kepler spent his later years in a deadly struggle with both Protestantism and Catholicism. Bacon and Hobbes lived in a country where their personal safety was fairly secure, nevertheless Bacon disguised his position by using large words and Hobbes was untroubled because he accepted the religion of his sovereign.

If the position of those was difficult who tried to keep themselves strictly within the limits of science, how much more fraught with personal danger was the position of those who openly constructed a new metaphysics? It would mean that a challenge was issued to the old Scholasticism by the same human reason that had already challenged and overthrown the old science. The group of men who did this were the Rationalists. The Rationalists were interested in science, but they were more interested in the metaphysical problems that science aroused. The human reason had been successful in the reconstruction of physics by the use of mathematics. Why should it not also be able to reconstruct metaphysics and set it, too, upon a mathematical basis? The leaders of this school were Descartes, Spinoza, Leibnitz, and the Occasionalists,――Malebranche and Geulincx. The Rationalists advanced a new conception not only of nature, but of God; new theories not only of the human body, but of the soul. Their task was the dangerous one of bravely invading the hitherto impregnable realms of the spirit.

The task of the Rationalists was rendered the more difficult because, for the first time in the history of European thought, the inner and outer worlds had been completely sundered. For the first time do we meet with a clear-cut and positive dualism. The history of the growth of this dualism had been a long one, and to it the Greek Sophist, the Stoic, and the Christian had each contributed his share. However, Galileo and his fellow scientists in this period of the Renaissance had so reconstructed the old “world of nature” that it had become irreconcilable to the “world of grace.” These scientists believed that nature must be made to explain itself; its events must be conceived as necessitated; its processes as having the inevitableness of a machine. From the revolutions of the planets to the circulation of the blood, the movements of nature can be measured. The law of nature, that is conceived to underlie all this science, is mechanical causation. The researches of the scientists of the Renaissance had yielded a rich world of brute, inevitable, and scientific facts, and these stood in absolute fundamental contrast to the world of spiritual facts which were embodied in the church dogma. Apparently the problem of reconciling the “world of nature” and the “world of grace” had been solved by St. Thomas Aquinas in mediæval times. Now, however, the “world of nature” had been so reconstructed that the question was re-opened. How is the new “world of nature” to be brought into harmonious relation with that old, persistent, and settled dogma of the church? How can the newly conceived mechanism of nature be harmonized with the realm of free conscious spirits, without giving up the conception of God as a rational being, and also without depriving the soul of its power of initiation? The new science had therefore made it especially difficult on the one hand to reconcile a mechanical universe with an omnipotent God, and on the other to reconcile the mechanical human body with the free soul.

The struggle of the Renaissance with the Middle Ages is therefore concentrated in the development of the doctrine of this Rationalist School. It is studied here even better than by reading the two periods side by side. In Rationalism the Scholasticism of the Middle Ages and the Science of the Renaissance meet. Rationalism was a new science, but it was a new theology as well. It was a new scholastic philosophy; for, while the Rationalists thought that they were giving the death blow to mediæval philosophy, they were instead only replacing it with another scholasticism. In their attempt, by means of the mechanical theory, to get an absolute system of knowledge upon which thought can rest, the Rationalists were acting in the spirit of the schoolmen. In fact, no schoolman ever showed more vigor or more dogmatic confidence in his philosophy. To the mathematical eye of the Rationalist there was absolutely nothing mysterious in the physical universe or in the spiritual realm. All things in heaven and earth could be made clear. The declaration of the Rationalists was the call of freedom, but it was as hazardous as it was ambitious; and the church with its assured revelations always stood opposed to the realization of freedom. So we shall find Descartes spending his whole life trying to trim his sails that he may not offend the Inquisition; Spinoza saving himself from both the Jews and the Christians by living in obscurity and publishing nothing; Leibnitz constructing philosophy with the avowed purpose of reconciling science and religion.

=The Mental Conflict in Descartes.= The strife between the spirit of the Middle Ages and that of the Renaissance appears in Descartes more strikingly than in any other thinker of this time. He shows, on the one hand, all the conservatism of a churchman of mediæval time in his respect for institutional authority; on the other hand, his intellectual activity places him among the leading scientists of the Renaissance. In no other thinker does the conflict between the Old and the New appear so unsettling; in none does the antagonism between the scholastic world of spiritual things and the mechanical world of science appear so irreconcilable. He suffered a life-long mental strife, for within himself mediævalism and science were engaged in an unending dramatic struggle. The philosophy of Descartes was a compromise between his traditions and his scientific genius; and his philosophy never overcame his conflicting motives. The admirers of Descartes have called him the father of modern thought, and this is partly true. The father of the modern scientific method was Galileo. Descartes, on the other hand, pointed out the incontestable principle from which modern thought has proceeded; he won his place in the history of philosophy by attempting to harmonize the old scholasticism with the new science under this single principle.

=The Life and Philosophical Writings of Descartes= (1596–1650).[26]

(1) _As Child and Student_ (1596–1613).

At home until he was eight years old (1596– 1604).

At the Jesuit school at La Flèche until he was seventeen (1604–1613).

(2) _As Traveler_ (1613–1628). Descartes studies “the book of the world.”

At Paris (1613–1617), in retirement and study.

In Holland (1617–1619), nominally attached to the army of Maurice.

First Journey (1619–1621), going through Bavaria, Austria, north to the shores of the Baltic and back to Holland. The greater part of these two years were spent in Bohemia, enrolled in the army of the Emperor. He was on this journey when his mental crisis occurred,――at Neuberg, in Austria, in 1619. It was then that he discovered either analytical geometry or the fundamental principle of his philosophy.

In Paris again, 1623.

Second Journey (1623–1625), to Switzerland and Italy, making a pilgrimage to the shrine of Loretto.

(3) _As Writer_ (1629–1650).

In Holland (1629–1649). For the sake of absolute seclusion from inquisitive visitors, Descartes changed his residence in Holland twenty-four times and lived in thirteen places. All his correspondence passed through Mersenne. During these twenty years he made three journeys to France. Thus this period of absolute retirement became his period of literary production, chiefly between the years 1635 and 1644. He wrote his

_Method_ (1635–1637).

_Meditations_ (1629–1641).

_Le Monde_ (1630–1632), published posthumously.

_Principles_ (1641–1644).

_Passions_ (1646–1649).

(4) _In Stockholm, Sweden_ (1649–1650). The romantic side of the life of Descartes appears in his book on the _Passions_, which he wrote for the Princess Elizabeth, and also in his acceptance of the invitation of the Queen of Sweden to reside at her court and become her tutor. He died there from the rigors of the climate after a residence of one year.

=The Two Conflicting Influences upon the Thought of Descartes.= On the one hand, all the ties of inheritance, family influence, and early education allied Descartes with the spirit of the Middle Ages. A delicate constitution made him shrink from public controversy and the public eye. He even made a half apology for his pursuit of science by saying that he was seeking to reform his own life, and that it was absurd for an individual to attempt to reform a state. His family on both sides belonged to the landed gentry, and he was therefore bound by caste to the support of institutional authority. He was educated in the Jesuit school of La Flèche, and this most conservative of ecclesiastical influences restrained him from following the logical conclusions of his own thought. He was therefore both physically timid and intellectually aloof. In 1632 he was about to publish _Le Monde_, which was a scientific description of the origin and nature of the universe, and agrees in part with the Copernican theory. It was a treatise which would naturally conflict with the teaching of the church. He learned of the trial of Galileo at Rome, and he never dared to publish the book.

The rival spirit speaking in Descartes was the new scientific spirit of the Renaissance. He had a genius for mathematics even when he was at school at La Flèche. On his going to Paris he became the centre of the most notable scientific circle in France――a circle composed of such men as the Abbé Claude Picot, the physician Villebressieux, the optician Ferrier, the mathematician Mersenne, and many other scientists and theologians. But he became dissatisfied and made some long journeys in order to study “the book of the world.” His discovery of his method and his philosophical principle was the result. In mathematics he was the discoverer of analytical geometry and was the first to represent powers by exponents; in physics he stated the principle of the refraction of light in trigonometrical form; he explained the rainbow; he weighed the air. The same industrious application of the new scientific methods that yielded great results in science, also resulted in his development of his philosophy. Love for original discovery made Descartes disdainful of all scientific authorities and even contemptuous of his notable contemporaries, Galileo and Harvey. He mentions by name Plato, Aristotle, Epicurus, Campanella, Telesio, and Bruno, but he claimed that he learned nothing from any one except Kepler. He felt himself to be above criticism, and in his self-arrogating dogmatism he is the type of the modern practical individualist. He defined truth as candor to one’s self, and both in his practical life and in his theoretical ideal there is an entire absence of utilitarianism.

=The Method of Descartes.= Both science and scholasticism show themselves in the method of Descartes. He attempted to construct a philosophical method entirely in the scientific spirit of the Renaissance, but in the application of it he showed his scholastic training. Surfeited with inadequate and traditional methods he felt the need of some single principle by which all knowledge might be systematized, and he was sure that mathematics would furnish the key. Rational science was to Descartes only mathematics. Truth is to be found not in metaphysics, nor in empirical science. Descartes’ philosophical aim was to establish a universal mathematics. Descartes was not entirely faithful to Galileo’s mathematical principle in his employment of it, and his influence in metaphysics was thereby all the greater; for in the development of his method he found assistance in the traditional scholastic methods. Descartes was original in insisting upon finding the existence of an absolute and undeniable principle before any progress could be made. Such an absolute principle can be obtained only by an _inductive sifting of all ideas_. From this all further truths must be obtained by _deduction_. Every true philosophy must therefore be an induction or analysis of ideas, and secondly, a deduction or synthesis. _The great contribution of Descartes was therefore this: to the inductive method of Bacon and the deductive method of Galileo, he added an absolute principle which must be taken as the basis of both induction and deduction._[27]

=Induction――Provisional Doubt――The Ultimate Certainty of Consciousness.= The philosophical proclamation of Descartes was characteristically French, for he demanded the same return to an uncorrupted nature for the understanding that Rousseau many years later demanded for the heart. The first step of Descartes was also French in its demand for absolute clearness, which from his youth had shown him to be so passionately fond of mathematics. The way to such clearness is through provisional doubt. Let us purify the understanding by delivering it of the rubbish of traditional opinions, taken upon the say-so of others. By this negative induction of received knowledge, let us see if there is anything positive and certain. In Descartes’s _Meditations_, in “a dramatic dialogue with himself,” he portrays his own intellectual struggle to gain uncontaminated truth. He makes an induction of all kinds of knowledge and challenges each as it appears. Nothing is to be accepted as true until it has proved itself true. All facts are subjected to rigid scrutiny. Descartes doubts the testimony of the senses, the existence of the material world, the existence of God. But this induction is provisional, even if it is radical. While none of the usually accepted truths are found by him to be undeniable and absolute, yet Descartes has an ulterior purpose in challenging them. Greek skepticism had no further end than doubt, while at the other extreme Anselm and the orthodox scholastics had refused to doubt at all. The method of Descartes is contrasted both with that of Anselm and with that of the Skeptics, for he doubts in order that he may know. _Dubito ut intelligam._ Doubt is necessary, but only as a means to an end; and that end is knowledge. Descartes proclaimed for the modern individual the privilege and the duty of rationalizing his own beliefs.

In such an inductive sifting of traditional beliefs, are there any that can be called knowledge? Is there one whose reliability cannot be successfully doubted? Not a single one, except the thinking process itself. I am certain that I am conscious. Even when in my universal doubt I say that nothing is certain, I am at least certain that I doubt. I am, therefore, contradicting my universal skepticism. To doubt is to think; in doubting, consciousness is asserting its existence. Skepticism is self-contradictory. An induction of our ideas reveals at least this one absolutely certain principle: I, as thinking, am. _Cogito ergo sum._ My own existence is an intuitive truth that accompanies every state of mind. This is the best known portion of Descartes’s philosophy, and perhaps it is in part to the Latin formula of it that it owes its widespread acceptance. It is criticised as trifling, even if it be true; and as reasoning in a circle. Yet it must be remembered that Descartes does not intend the _ergo sum_ (“therefore I am”) to be a conclusion of a syllogism of which _Cogito_ (“I think”) is the minor premise. This formula is not an inference, but an intuition, which is revealed by induction as the certain background of all knowledge.

Three things are to be learned from this fundamental principle, said Descartes: (1) The first is that man has gained a criterion of truth. The characteristic of this principle that makes it reliable and certain is its clearness and distinctness. _Clearness and distinctness of ideas is the proof of their truth._ All true ideas will therefore have the mathematical and intuitive certainty that the idea of the existence of the self has. (2) The second lesson from this fundamental principle is that the existence of the soul is more certain than that of the body. The soul is more important and independent than the body. This is the subjective point of view of modern times. The modern man views the world as the representation or the creation of his thinking soul. (3) The third lesson from this principle concerns the nature of the soul. How long do you exist? As long as you think. (_Sum cogitans._) True existence is rational thinking, and God alone has it. Feelings and passions are obscure ideas.

=Deduction――The Implications of Consciousness.= For Descartes reality lies within the Self; and the next question before him is how to get out of the Self. Knowledge that is confined to the Self and its states is called, technically, solipsism. Such knowledge amounts to little; indeed, it is not knowledge at all. Certainty of self-existence is the minimum amount of knowledge――merely the starting point of knowledge. Descartes proposes to escape from this solipsism by the use of logic. His method from this point on is ostensibly deductive, although he introduces by the side door other ideas than the idea of Self to make his proof complete. Descartes maintains that any idea will be as true as the consciousness that accompanies it, just as a proposition in geometry partakes of the truth of the axioms from which it is derived. Now my consciousness contains many ideas; some of them seem to be the product of my imagination; some seem to be adventitious; some are innate. It is upon the innate ideas that Descartes depends to get him out of his solipsism, for they are not created by the Self and they have the qualities of truth――a conscious clearness and distinctness. Among these innate ideas is the idea of God as a perfect being.

=The Existence of God.[28]= As a deduction from consciousness, the idea of God would prove to be a very useful one to Descartes, provided it had reality. For it is evident that consciousness can testify only to the existence of itself and its own states. How do I know the reality of anything else? Am I confined within the circle of my own thinking? Is all that I can say of this or that, “It is real to me”? Are all things only the phantasmagoria of my own brain, testifying only to the existence of myself? Descartes thought that the idea of God relieved him of this solipsism. If he could demonstrate God’s existence, he would then be able to demonstrate the existence of the material universe. The problem was so highly important to Descartes that he threw it into several different arguments. The complications with which these arguments are filled must be passed over here, and the arguments stated in their simplest forms.

(a) Two are ontological arguments, that is, arguments from the character of the conception of God’s nature.

(1) _A Simple Deduction._ If I have in my consciousness any idea as clear and distinct as my idea of Myself, it must have existence like Myself. My idea of God has just that clearness and distinctness; and therefore God exists.

(2) _The Geometrical Argument_, so called by Descartes. Some ideas have properties so immutable that, when we think the ideas, we necessarily think their properties. Such is the idea of a triangle; when I think of a triangle, I must think of it as having its three angles equal to two right angles. Such is also my idea of God; I must think of him as perfect and existing. He would not be God, _i. e._ a perfect Being, if He did not exist.

The reader will recognize this as a re-statement of the argument by St. Anselm. As such it raised a tempest of controversy in Descartes’ time, and was attacked from all sides.

(b) Two are causal arguments, that is, based on the assumption of the equality of cause and effect. Only one of these arguments will be cited here. This is known as

_The Cartesian Argument._ I have an idea of a perfect Being. This idea must have an adequate cause. Therefore God must exist, for only He, and no imperfect being, can be the adequate cause of my idea of perfection.

The ontological arguments given by Descartes are evidently deductions from the certainty of self-consciousness. The question which we immediately raise concerning them is, Are they true? As to the causal arguments, Descartes is breaking away from his original assumption, viz., that self-consciousness is the only certainty, and is introducing another assumption, viz., the certainty of the law of cause. The question, then, that the thoughtful student asks, is, Does Descartes really escape from his solipsism?

=The Reality of Matter.= It will be seen that Descartes is trying to deduce from the certainty of the idea of self-consciousness the certainty of other ideas, as propositions are deduced in geometry from axioms. The existence of God is an implication of human consciousness. Now Descartes points out that the existence of matter is implied in the existence of God. Descartes is interested in material science, and it is important for him to prove the reality of matter. Here again his scholastic training comes into play. Since God has all the attributes of a perfect being, He must be veracious. If there were no God, but only a deceiving Devil, the external world might be only a fiction, created to deceive us. But God exists, and we can trust that He would not continually deceive men about the existence of nature. An atheist could have no science, but to Descartes,

“God’s in His heaven―― All’s right with the world.”

Of course, man is constantly in error about the character of physical things, but these errors arise from his misinterpretation of them. Nature in some form lies before man, or else God in His truthfulness does not exist. The essence of matter is extension (see below), and whatever my interpretation of it, something extended lies before me to be interpreted.

This is the skeleton upon which Descartes constructs his theory. Even this cursory examination of it shows the obvious attempt to explain “the world of grace” by the method of mathematics, and it is quite consistent with the spirit of the Renaissance. The existence of God and the existence of matter are deduced in turn from the axiom of all thought, the Self; while matter is further described as the extended or the measurable. Thus Descartes has tried to construct a bridge between the scholastic concepts and the science of the Renaissance. The three realities, the Self, God, and matter, which Descartes often speaks of as intuitively certain, have obviously a differing cogency. The reality of consciousness is the ground from which the other two are derived. In asserting its primacy, he is voicing the spirit of the Renaissance even more clearly than did Galileo and Bacon. For Descartes in this has gone back of the objective facts to a single subjective principle; whereas the deductive principles of Galileo were objective. In this respect Descartes is the founder of the subjective method of modern thought, and in identifying the Self as the reason he became the founder of rationalism. In any case he established a background for epistemology, or the theory of knowledge. But in his derivation of the other two realities――God and matter――he shows how persistent was the scholastic current in his thought. Although he declared them to be intuitively known, they evidently are not so in the same sense that self-consciousness is; and he felt obliged to support them by traditional scholastic arguments.

=God and the World.= Leaving these fundamental principles of Descartes, we now come to a consideration of a few of the details of his philosophy. Descartes’ world is a dualism in which conscious being stands in contrast with space objects. God is related to the world of mind on the one hand and to the world of matter on the other. The order in which Descartes came upon the three substances――the Self, God, and matter――is, however, not the order of their reality. In reality God is the _primary substance_, for He depends only upon Himself. Matter and the Self are _relative or created substances_, for they depend upon God. Matter and mind have different modes of appearing: the modes of matter are form, size, position, and motion. The modes of mind are ideas, judgments, and will. Thus mind is so essentially different from matter, as can be seen in their respective modes, that God stands in a different relation to each.

=The Relation of God to Matter.= Descartes here investigates the realm in which he has the deepest interest; but he makes a concession at the very beginning. He divests things of their qualities and finds the essence of matter to be extension. Qualities are not resident in things, but are the result of our sensations. Sense-perception is knowledge of qualities, and therefore obscure knowledge; while clear or intellectual knowledge is of quantities. But there is one quality common to matter,――extension. Space, extension, and matter are the same. There is no space that is empty, no matter that is not extended. An extended or material body has, however, in itself no principle of motion. It cannot move itself. It must be moved by an external cause, and the whole universe must be a mechanism whose movements have their first cause in God. Matter in its modes of motion and rest has God as its first cause or unmoved mover; and under matter is included everything extended,――inanimate objects, the lower animals, and the bodies of men. To this world of matter God stands in the relation of an inventor to his machine.

=The Relation of God to Minds.= The essential nature of minds is thought. Mind is therefore different from matter because it is unextended and free. The two relative substances have nothing in common except that they are related to God. The relation of God to minds is, however, very different from His relation to matter. God is not the unmoved mover of minds, but He is the perfect and infinite mind to which our finite minds turn as their ideal. God thinks and wills perfectly what we think and will imperfectly. He is not the mechanical but the teleological cause of minds, their _ens perfectissimum_, the goal of all mental aspiration.

=The Relation of Mind and Body.= In proportion as Descartes clearly defined mind and body, and referred each back to its own principle, the impossibility of connecting the two became apparent. Descartes intended that his theory should, above everything else, clear philosophy of all obscurities. So he divided the world into two relative substances,――mind and matter,――each operating in its own realm, each exclusive of the other. The intention of Descartes is to be a consistent dualist. But there was one point where, with one eye on the church, he had to qualify for ethical considerations his scientific principle of matter. That is the point where the human body acts upon the soul and the soul acts upon the body.

There was little trouble for Descartes in conceiving the movements of inanimate bodies, plants, and all the lower animals as purely mechanical and automatic, with their first cause in God. From his own investigations he felt obliged to regard many of the human functions as automatic also. But his ethical and theological interests compelled him to think of man as exalted above the rest of creation. Theology has always been in a sense aristocratic, and has drawn a line between man and other things. Man alone has a soul in his body. The soul of man is immortal and free, and must therefore have control over the body; nevertheless the soul of man must be conscious of the impressions that come through the body. Here the science of the Renaissance and the scholasticism of the Middle Ages refuse to be reconciled in the philosophy of Descartes. When it became a question between Descartes’ scientific theory of matter operating itself mechanically and the church doctrine of a spiritual will operating the matter of the human body, the scientific theory had to yield. How does Descartes yield gracefully to the theological requirements and bring together the two unlike worlds of matter and mind in the human personality?

Descartes’ explanation of the relation of human mind and body reminds us of the mythical explanations of Paracelsus. The soul is united to all parts of the body, but its point of contact with the body is the pineal gland, and this contact is made possible through the animal spirits (_spiritus animales_) or the fire atoms in the blood, a revived Greek conception. The pineal gland is a ganglion in the centre of the brain, which biologists tell us is a defunct eye, but which Descartes conceived to be the seat of the soul. Descartes maintained that the animal spirits, having been distilled by the heart, ascend by mechanical laws from the heart to the brain, and then descend to the nerves and muscles. When they pass through the pineal gland, they come in contact with the soul. The soul exercises influence on the body by slightly moving the gland and diverting the animal spirits. In this way the emotions and sensations are to be explained. The movement of the pineal gland by the animal spirits causes sensations in the soul; the movement of the gland by the soul changes the movement of the animal spirits, and is an exhibition of free action. But this does not add to or subtract from the energy. It merely changes the direction of energy.

=The Influence of Descartes.= Although the philosophy of Descartes was forbidden in the University of Oxford, was proscribed by the Calvinists in Holland, and his works were placed upon the Index by the Catholics, it created a profound impression on the theology, science, and literature of the seventeenth century. It spread over Europe in a somewhat similar way to the Darwinian evolution theory in modern times. Its success was immense, many standard men rallied to its support, and everything before Descartes was considered to be antiquated. Among philosophers his doctrine had an internal development in a natural way along the lines of the problems which he had left unsolved. A philosophical development, the source of which can be traced directly back to Descartes, went on until Kant published his _Critique_ in 1781. This has later been called the School of Rationalism in Germany, France, and Holland. The most important members of this school――the Occasionalists, Spinoza, Leibnitz, and Wolff――we shall consider in their place. Descartes had an important immediate following in the group, who go by the name of Occasionalists; but his most important successor, who can hardly be called his disciple, was Spinoza.

Descartes’ method had a peculiar fate. His followers misunderstood it, exactly reversed it, and obtained very fruitful results. Descartes himself had hoped to see induction employed in most metaphysical problems. He regarded deduction as of use only in proceeding from one self-evident fact to another. But the following Rationalists used the deductive method entirely and tried to systematize ethics after the manner of Euclid. They deduced their systems from some assumed principle. This tendency was first seen in the Port Royal logic, and was completed by Spinoza.

=The Relation of the Occasionalists and Spinoza to Descartes.= The development of the doctrines of the Occasionalists and Spinoza from Descartes was an attempt to make clear the conception of _substance_. Since substance was the most important scholastic category, it is easy to see why Spinoza’s teaching became thoroughly scholastic. Descartes had used the term “substance” in a very loose way to apply to God as infinite, and to minds and bodies as finite. He speaks of God as the only substance, and yet of consciousness and bodies as created substances. Such ambiguity must be overcome, if a philosophy which prided itself on making everything “clear and distinct” was to stand. Descartes had fallen short of justifying his attempt to put metaphysics completely upon a mathematical basis, although this had been his original problem. The obscurity of the spiritual world still remained, because Descartes had left the concept of the spiritual substance undefined. The world of the spirit was still an unknown country. The spiritual substance had not been made clear and distinct, and there still remained the ontological problem of the relation between mind and matter, and the psychological problem of the relation between the individual soul and its body.

Descartes had, however, defined clearly the concept of the substance of matter――the substance with which the natural scientist works. He had accomplished this, to be sure, by destroying the essential distinctions between material things. A “thing” is essentially a substance in which many qualities inhere, _e. g._ a piece of sugar having whiteness, sweetness, etc. Material substances were alike in that all were essentially extension. All else besides extension in any particular finite thing was a modification of extension. A lump of sugar was essentially the same as a lump of salt in that both were extension; the saltness, sweetness, etc., were secondary. Now this makes the nature of bodies very clear; and Descartes proposed to reduce the substance of the states of mind to the same clearness, but he did not do it. He was interested in natural science and he developed his rationalism only with reference to matter. Bodies are parts of space or corpuscles, which are mathematically infinitely divisible, but perceptually are not further divisible. As far as he went, Descartes was clear enough.

The Occasionalists and Spinoza represent the second stage in the development of Rationalism. Both tried by making clear the meaning of spiritual substance to define the relationship of God to the material world. Both tried to state the problem in other words, to overcome the dualism between mind and matter, and to reconstruct the old “world of grace” so that it would be consistent with the new world of science. The Occasionalists, whose chief exponents were Malebranche and Geulincx, we shall dismiss with only a few words, while considerable attention must be given to the teaching of Spinoza. Malebranche tried to do for the mental world what Descartes had done for the world of matter. Since no knowledge is possible except in God, he claimed that the modes of finite minds――our ideas, judgments, imaginations――are alike in essence in being modifications of the universal reason of God. God is so far the “place of minds” as space is the place of bodies. All our ideas participate in God’s reason, and all our volitions are the modifications of the will of the Divine, just as bodies are modifications of extension. What then is the relation, asked Geulincx, between bodily movement and the states of consciousness? Why does my arm move when I wish to move it? By the mediatory power of God. The thought in my mind is the “occasional cause” of the movement of my arm, while God is the true cause of the movement. The movement of the human body is therefore, like the movement of all matter, a continuous miracle caused by an ever watchful Deity, who keeps body and mind in harmony. Spinoza completed his pantheism before Malebranche had prepared the way. He formulated a complete doctrine of substance, conceiving material bodies to be essentially the same in being modes of extension, and mental phenomena to be essentially alike in being modes of thought. But more important was his further teaching that on that account the two series have no relation to each other. That is to say, Spinoza reduced the whole difficulty to clearness and distinctness by reducing the three substances of Descartes to one. For this reason Spinoza was a more complete Rationalist than Descartes; and he was assisted in this construction of a mathematical Rationalism by two facts: he held himself strictly to the deductive method, and he was free from social and ecclesiastical ties. Spinoza is the truest utterance of his time in its effort to make all things clear; and this is not contradicted by the fact that he had little influence in shaping contemporary thought.

Illustration: BARUCH DE SPINOZA

(Pollock (_Spinoza, His Life and Philosophy_, p. xxvi) says that only three of the portraits of Spinoza may reasonably be considered authentic. One is a miniature of the philosopher in the Summer Palace at the Hague; the second is a painting in the Town Museum at the Hague; the third is the one given here, which is an engraving found in copies of the original edition of Spinoza’s Posthumous Works (1677). This portrait seems to be somewhat idealized, but of the three it is the most artistic and lifelike.)

=The Historical Place of Spinoza.=[29] Spinoza did not get full standing nor was he widely read, until Lessing, one hundred years later, resurrected his teaching and Goethe adopted it. He produced what the Renaissance was striving for, but what the Renaissance could not yet grasp,――the complete logical formulation of its deepest thought. Spinoza produced the only great conception of the world during this period, and it excited the hostility of contemporary Catholics, Protestants, and free-thinkers alike. The product of his thinking was a new systematic scholasticism, which, if the time had been ready for it, would have entirely superseded the mediæval. He succeeded in placing metaphysics upon a scientific and mathematical basis, for his philosophy was not only logical in its content but mathematical in its form. Spinoza’s philosophy is the Renaissance expression of mediæval scholasticism,――the expression of that rationalism that underlies both the thought of the Middle Ages and the Renaissance. It is as if Thomas Aquinas had been transported into the Renaissance, and finding that science would not support and explain dogma, had conformed dogma systematically to the new science. Mathematically science was the new dogma. Spinoza is the last word of mediævalism, although his language is the science of the Renaissance. The utterance of Spinoza sounds strange because, while his thought is mediæval, his expression and form are scientific.

Spinozism had a revival in the eighteenth century.[30] It formed the background of the philosophy of Herder and that of the author of the _♦Wolfenbüttel Fragments_. The connection of Lessing and Spinoza was a matter of active controversy at that time. Spinoza was the great influence upon Goethe. In the nineteenth century in England Coleridge reproduced from Spinoza’s _Ethics_ the doctrine of an all-pervading love and reason.

Spinoza strove before everything else for a unitary system, and yet it is interesting to see how much he has been honored from different quarters. Artists, religious devotees, poets, idealists, materialists, and scientists have found in him their truest expression. This is not only because each has found something different, but because his philosophy had actually a many-sided character. His teaching had the advantage of being thoroughly radical. Bad systems of philosophy are impossible, because they are contradictory. While no one knows that any system corresponds to fact, still it is possible that a radical system may have such correspondence. Spinoza’s system is comprehensive, and therefore has struck sympathetic chords in differing thinkers.

=The Influences upon Spinoza.= =1. His Jewish Training.= Spinoza was born a Jew and remained a member of the Synagogue until he was excommunicated at the age of twenty-four. Although he was the original genius who transcends his limitations, his young mind was moulded after the Jewish type. He received the strictly religious training of the Jewish boy in the Jewish academy at Amsterdam, where he learned a trade in connection with his studies. He studied the Talmud, mediæval Jewish philosophy, especially the writings of Maimonides (twelfth century), and the Cabalistic literature. In a Jewish curriculum the classical languages had no place; and mathematics, except arithmetic, was generally overlooked. His early instruction emphasized above everything else the unity and the supremely transcendent, theistic character of God.

However, his separation from the Synagogue at this early age could not but modify his theology. It made him a free Jew. He was no longer under the restraints of Jewish traditions. While he never abandoned his belief in God as a unity, he gave up his belief in the transcendent theistic God of the Hebrew prophets; and he differed from the contemporary Jewish Cabalistic teaching of emanations from God. He seems to have so modified the orthodox Hebrew conception of God that it rather resembles that of the mediæval mystic Christian. Perhaps the influence of Bruno upon his thought may account for its final shape.

=2. His Impulse from the New Science――Descartes’ Influence.= The “free thinking” for which Spinoza was excommunicated by the Synagogue was obtained first from his instruction in the school of Van der Ende, a physician of daring naturalistic tendencies. This was when he was eighteen. Spinoza had already learned Italian and French; Spanish, Portuguese, Dutch, and Hebrew were his native tongues; Van der Ende taught him German and Latin, and introduced him to the science of the time. It was then that he read Descartes, whose philosophy he made the basis of his own. Spinoza was not an inventive genius like Descartes and Leibnitz, but he was more rigidly systematic than either. He was by nature a thinker who was obliged to carry his thought through to its logical conclusions. He had already, at this early age of eighteen, begun to make independent theological excursions. Consequently the mathematical methods of Descartes furnished him a method, and Van der Ende gave him the encouragement for carrying out his independent thinking unrelentingly to its logical end. To state his modified Jewish conception of God in mathematical terms became his task, and his success in thus stating it, with Descartes as a starting point, made him the most complete representative of Rationalism.

=3. His Acquaintance with the Collegiants.= After his expulsion from his kindred, he lived for seven years with a sect of Baptist Quakers called Collegiants. This was a dissenting religious body without priests or set forms of worship. The members were simple, pious people, who regarded moral living as superior to creed; and Spinoza’s life in their midst must have determined to some degree the lines of his thought. To a man of Spinoza’s simplicity of mind and kindly disposition, the Collegiants would prove to be not only congenial companions in his hours of distress, but they would confirm his own love for the ethical as an ideal. Spinoza says that the motive of his philosophy is a practical one; that he is seeking that which would “enable me to enjoy continuous and supreme and unending happiness.” He is seeking a theory of life that would aid in allaying the unrest of his time; and he is the only philosopher who has called his metaphysics _Ethics_. The humaneness of his doctrine, the practical purpose of his writings, and the ethical ideal that informed his whole life had at least their reinforcement, and perhaps their origin, in his contact with the Collegiants during this critical period. His life with this sect influenced him in his refusal to accept the chair of philosophy at the University of Heidelberg, and to remain content to be the obscure grinder of optical lenses.

=The Life and Philosophical Writings of Spinoza=[31] (1632–1677). The history of philosophy presents in the person of Spinoza a lovable, interesting, and striking character, as well as the author of one of the profoundest of philosophical systems. His life was one of social isolation and retirement rather than of solitude. The Jews to whom he belonged lived a kind of double exile――they were exiled from their home in Spain, and they lived by themselves apart from the people of Amsterdam. When Spinoza was excommunicated by his brethren, he suffered, therefore, a threefold exile. Moreover, Spinoza was not only excommunicated by his people, but he was hated by the contemporary Catholics, Protestants, and the prevailing Cartesian school. Even the free-thinker, Hume, spoke of him as “the infamous Spinoza,” and another philosopher described his philosophy as “the hideous hypothesis of Spinoza.” But his isolation was far from solitude, and he had many eminent and faithful friends and a notable correspondence. Of his short life of forty-five years, he spent twenty-four, or more than half, as a member of the Jewish synagogue. During the next seven years he found refuge among the Collegiants. In the last fourteen years of his life he became widely known, mainly through the _Theological-Political Tract_, published in 1670, the only one of his writings which he himself published. This brought him the call to the University of Heidelberg, which he declined. His life may be conveniently divided into three periods, as follows:――

1. _In Israel_ (1632–1656). Spinoza was educated at the Jewish academy at Amsterdam, where he studied theology and learned a trade, according to the Jewish custom. This trade was the grinding of optical lenses; that is, he became an optician, and this required some knowledge of mathematics and physics. During these years he got instruction from Van der Ende in science and Latin. He also read Descartes and learned many languages. He wrote a compendium of a Hebrew Grammar, of which the date is doubtful. In 1656 he was excommunicated by the synagogue. The charges brought against him were that: (1) he denied that the Old Testament taught the doctrine of immortality; (2) he affirmed that angels may be only phantoms or ideas in men’s minds; (3) he affirmed that God may have a body.

2. _In Retirement_ (1656–1663). Spinoza spent this time with the Collegiants, and this was his most fruitful intellectual period. He brought his ontology, ethics, politics, and physics into a unified system; and he formulated his theory of determinism and his mathematical method. In 1658–1661 he was writing his so-called _Short Treatise_, “concerning God, man and his well-being.” This was the first draft of his _Ethics_. In 1656–1662 he was writing his _Improvement of the Understanding_. In 1662–1663 he wrote a summary of the principles of Descartes.

3. _In the Public Eye_ (1663–1677). During this period Spinoza lived at or near the Hague, where he had many visitors and a large correspondence.[32] He was an intimate friend of the brothers DeWitte, who made so large a part of the political history of the country. In 1662–1665 he was writing his _Ethics_, his monumental work. In 1663–1670 he wrote and published the _Theological-Political Treatise_, the only work published during his life. Although received with horror, it was widely read. It aimed to show that the _Bible_ is history. In 1673 he declined the call to the University of Heidelberg. Just before his death, in 1677, he wrote the fragment of the _Political Treatise_.

=The Method of Spinoza.= The method which Spinoza employed in writing his _Ethics_ must not be regarded by the reader as a fantastic dress that he capriciously chose. It had for Spinoza a real and not merely an external significance. On taking up the book, one finds philosophy treated exactly as Euclid treated his geometry. Beginning with a number of definitions and axioms, there are deduced, step by step, propositions with appended scholia and corollaries. To Spinoza this was not pressing philosophy into an artificial and rigid form, but was only the natural mode of philosophical expression. For, in the first place, if the new method of science had proved itself successful in treating physical phenomena, why should not the same method have the same success with problems of the world of the spirit――and in this way bring the two worlds into harmony? By deduction one could then arrive at absolute certainty and unassailable proof of the solutions of metaphysical problems that had long vexed the Middle Ages. With the perfect geometrical method all problems in heaven and earth could be solved. In the second place, the religious conviction of Spinoza that all things come from God required the deductive method to explain them. The order in which we should study phenomena should correspond to the real order in which they stand to God. God is the ground or reason of things, and all are derived from Him as consequents. The deduction of the relation of finite things to God will correspond to the real relation in which God stands to them.

=The Fundamental Principle in Spinoza’s Philosophy.= The philosophy of Spinoza seems to be Cartesian in every respect except one; and that one difference was like the leaven in the lump――it transformed his philosophy into a radically different one from that of Descartes. Spinoza’s point of departure was the philosophy of Descartes, all his presuppositions are the fundamental principles of Descartes, and the structure of his system seems to be that of Descartes. He has the same respect for the power of the reason to know all truth, the same faith in the omnipotence of the mathematical method, the same general conception of substance, the same idea of the qualitative difference between the worlds of thought and extension, the same belief in the mechanical structure of the world of nature. He made these his own and accentuated them. But he added to these a new and transforming principle: he conceived that the substance, God, is not merely one object of knowledge, but _He is the only object of knowledge_. He is the only substance, and finite things are only modifications of Him. Finite things are alike at bottom, and to know them truly is to know God.

This new principle transforms all the Cartesian elements in Spinoza’s teaching. It changes the Cartesian theism into a pantheism; it supplants Descartes’ theological orthodoxy with a naturalism and Descartes’ doctrine of freedom with a determinism; and it turns the cultured aloofness of Descartes into a benevolent mysticism. This new principle becomes “the head of the corner.” The oneness and universality of God is the single proposition from which Spinoza deduced his whole philosophy. God is the ultimate ground whose existence must be real, because it is conceived. The intrinsic scholasticism of the philosophy of Spinoza appears in his definition of substance, for it is only a condensed statement of St. Anselm’s argument for the existence of God. Spinoza says, “By substance I mean that which is in itself and conceived through itself alone.” There are, therefore, two kinds of things: the thing that has existence in itself and the things that have existence in something else. God stands alone in the first class; all other things make up the second class. Spinoza’s world is divided into two parts: God and the modes of God. God is self-explanatory and self-existent, while everything else is explained through Him. The only object of knowledge and the single presupposition of existence is God. In a phrase that has become classic, Novalis described Spinoza as a “God-intoxicated man.”

=Three Central Problems in Spinoza’s Teaching.= We have already noted that Spinoza was the chief exponent of “clearness and distinctness” in this epoch when all mysteries were to be revealed. He sought to articulate a metaphysics that would spread out the plan of the world like a demonstration in geometry. His definition of substance is perfectly intelligible; he accepted the mathematical analysis of the material world into a world of extension, and that of the world of conscious states into one of thought――all this for the sake of simplification and clearness. How simple such a philosophy at the first blush appears――the world is God and his modifications. As a matter of fact it is one of the many examples of the irony of history that the philosophy of Spinoza is one of the most difficult to interpret. Its difficulties do not arise from its having a novel point of view, for on the contrary it is one that appeals strongly to the popular imagination. Its difficulties arise from its very simplicity, for, after all, human life is so rich and varied that a simple formula will hardly express it. From beginning to end Spinoza’s thought has a vagueness for which the beginner in vain strives to find the cause. The cause lies in the seemingly simple principle that God is all that really exists, and yet the world consists of God and other things.

From Spinoza’s effort to simplify matters emerged three central problems: (1) The problem of the all-inclusiveness of God――the problem of pantheism; (2) The problem of the unity of God――the problem of mysticism; (3) The problem of the salvation of man――an ethical problem. We shall now consider these problems in order.

=The Pantheism of Spinoza――The All-Inclusiveness of God.= That Spinoza’s philosophy is a pantheism appears at the outset in his conception of substance; for the substance is all that really is. Descartes had conceived of three substances,――God as the absolute substance, and mind and matter as the two relative substances. But to Spinoza there can be only one substance; for if there were two or more, no one would be substance, since each would be conceived through the others. If we think at all, we must think of substance as all-inclusive. One might suppose that this preliminary statement would be all that Spinoza could say about life: all that really is, is substance; other things do not exist. But that would be a misinterpretation of Spinoza. He does not mean that finite things are mere nothings. They exist as unrealities; they exist as negations of the substance. If you prick into the finite world, it does not collapse, like a balloon. It still exists as an unreality.

No person ever had the idea of infinity so profoundly as did Spinoza. His idea of infinity is not merely that of the infinity of time and space, which indeed affords a tremendous variety of possible constructions, since space and time are each infinite. To Spinoza the infinity of the substance is much more than these possible combinations of time and space, for corresponding to the time and space series is a series of mental states. Every event has a reason. Every one of the infinity of events in the world of extension is paralleled by some state of thought. But this is by no means the whole story about Spinoza’s conception of infinity. Besides the infinite world of time and space and the infinite world of corresponding thought, the substance to Spinoza possesses an infinity of other attributes, each of which is infinite. Spinoza piles up infinities upon infinities, and thus conceives the substance as an infinity in an overwhelming sense. Only two of the infinite modes appear to our limited human discernment: the infinity of the mode of extension, and the infinity of the mode of thought.

Spinoza begins at once to tell us about the forms in which the all-inclusive God appears to us. First, the substance has two attributes, thought and extension. An attribute is “that which the intellect perceives as constituting the essence of the substance.” Each attribute in its turn manifests itself in modes: thought appears in the modes of intellect and will, extension in the modes of rest and motion.

Substance = God. ┌────────┴────────┐ Attributes = Thought Extension. ┌────┴────┐ ┌───┴───┐ Modes = Intellect Will Motion Rest.

This bare skeleton of our rich and varied world appears very much the same as that which one might find beneath Descartes’ philosophy. However, Spinoza’s conception of substance transforms it into a framework of a very different kind of philosophy. Since God is the inclusive reality of it all, we have here a pantheism instead of a dualism. The antithesis which in Descartes’ philosophy was between extension and thought, now in Spinoza’s teaching is between God and other things.

What is the place of the attributes and modes in the all-embracing and real substance? As to the attributes, Spinoza maintained that we, as finite beings, do not know God in His character as substance, but that He always appears to us through His attributes of thought and extension. There are only these two attributes that the human mind can know, although God as an infinite being must possess an infinite number of such attributes. In our human world all things are either thought-things or extension-things. Each of these two attributes is infinite after its kind. Each fully expresses an aspect of God without depreciating the value of the other. Each is fully adequate, just as a table may be both white and hard without either quality infringing upon the other. The attributes are the substance made more concrete. The modes are in turn modifications of the attributes and more concrete expressions of them and of the substance. Each mode is infinite after its kind. Since God exists only in reality, He would not supposably see from His point of view the world laid out in attributes and modes; for these are only human ways of interpreting Him. While the critics agree that the modes are human interpretations of the attributes and therefore unreal, they disagree about the relation of the attributes to God. Some maintain that the attributes are merely human ways of seeing the substance, analogously to the modes――as if we saw God now as thought and now as extension; others maintain that God is nothing other than the sum of the attributes; of extension, thought, and the unknown, infinite, other attributes. The difficulty lays bare the nerve of the problem of pantheism, and probably Spinoza was not clear in his own mind about the relation of the attributes to the substance.

Spinoza speaks more definitely upon this same problem of the relation of the modes to God. Is God the sum-total of all existent things, or is He the principle behind them? Spinoza says that God is both. God is the cause of the world, not cause in the way that the term is commonly used nor in the sense that Descartes used it. God is not to existent things the first cause or the unmoved mover of matter, or the teleological cause of thought, as in Descartes. He is cause in the sense that a triangle is the cause of its own three sides. He is the rational ground (_ratio essendi_) or the logical reason for the being of things. In this sense God may be regarded as the cause _both_ in the sense that He is the sum-total of existent things or modes (_natura naturata_), and in the sense that He is the immanent and energizing principle of existent things (_natura naturans_). These conceptions as well as their phrases Spinoza probably got from Bruno.

The world is, therefore, related to God in that it follows directly from the nature of God; God is related to the world in that He is the logical ground of the world. Is God the creator of the world? No, He is the world. Is God a person? Is He a self-conscious being like ourselves,――an individual? No. The thought-aspect of God includes our thought, but it is the very different infinite thought; the extension-aspect of God includes our body, but it is the very different infinite body. God has soul and body and an infinite number of other aspects. _God is_――an unchanging, self-dependent being, whose modifications are necessarily determined in their relation to Him and to one another. Spinoza conceived the character of God exactly from the nature of geometry. Just as all geometrical conclusions follow from the nature of space and exist in determined and fixed relations to one another, so everything finite follows from the nature of the Infinite, and each finite thing is in a rigid chain of finite things of its own kind――a chain without beginning or end. The necessity of the divine nature appears in all, not as a series of emanations from God, but in a series, each member of which is determined equally by Him.

=The Mysticism of Spinoza.= _From the point of view of man_, mysticism in speculative or religious thought has reference to the immediate apprehension of God. Mysticism frequently accompanies pantheism, and _from the point of view of God_ refers to the oneness of His all-inclusive nature. Spinoza’s pantheism is also a mysticism which involves the immediate apprehension of the divine by the human; it involves the oneness of God and man. More often than otherwise mysticism is animated by a religious motive, and Spinoza’s philosophy is profoundly religious. We have already seen similar mysticism in the Orphic-Pythagorean sect which formed so great a peril to Greek culture in the sixth century B. C., in the neo-Pythagoreans and neo-Platonists at the beginning of this era, in many of the churchmen of the Middle Ages, especially Scotus Erigena and Meister Eckhart. Bruno and many of the Humanists were mystics, and if we should wish to go outside our field, we should find mysticism to be the prevailing attitude of mind of the great Oriental peoples. Mysticism frequently is accompanied by belief in occult spiritual appearances, but that is not necessarily the case; nor was it the case with Spinoza. Spinoza’s mysticism was purely intellectual. Although a religious philosophy with an immediate ethical bearing upon conduct, it was a scientific relationalism that could not tolerate the miraculous and the abnormal psychological phenomena (such as clairvoyance, hallucinations, etc.). Spinoza is, on the contrary, distinguished as a mystic because he interpreted the universe in entirely non-human terms. His great service to mysticism lies in divesting the reality of life of every human attribution and laying bare a mathematical skeleton. The desire of the period to find a greater unity in life was responded to by him in a mathematical mysticism. To him the universe is not only divided into parts, not only is there no opposition between God and the world, but life is so completely a rational thing that no exceptional phenomena can occur. He believed that any description of God or of nature in anthropomorphic terms disunites life. Spinoza dehumanized the universe, conceiving matter to consist of elements, and conceiving spirit to consist of simple ideas. He resolved the personality of man into parts for the sake of the unity of the universe, and he obtained scientific clearness at the expense of humanity. Thus, instead of being able to say with Descartes, “I think and therefore I am,” Spinoza could say, and wished only to say, “God thinks” (_Deus cogitat_).

Like the usual speculative mystic, Spinoza described his God in the terms of formal deductive logic. God is the most real being, _ens realissimum_. What is the most real being to a mystic? Would reality contain any finite quality such as the world around us contains? Can you say that God has this particular faculty, or is endowed with that concrete attribute? Does God enjoy, love, hate; does He create and destroy? But how can God be the real unity of the world unless He contains in Himself everything in the finite world? We approach here the threshold of _the problem of the concrete universal_, which has engaged the attention of so much of modern philosophy. A concrete universal is all-inclusive of finite existence, but at the same time is a self-consistent unity. In contrast with the concrete universal is the abstract universal, which is a unity, but outside of which all finite existence falls. While it was undoubtedly the concrete universal that Spinoza sought, his method could lead to nothing more concrete than the abstract universals of Plato and the Schoolmen. The world of finite things is included by Spinoza’s God in the same way that blocks are included by a string which has been tied around them.

Spinoza’s God is the most abstract entity which it is possible to conceive. All finite things fall outside Him. No quality can be predicated of Him, for to define Him is to limit Him. After the manner of the “negative theology” (see vol. i, p. 283), Spinoza refused to ascribe any quality to God. He does not feel, think, or will as we do, nor can extension be ascribed to Him in the sense of finite spaces. We can say only that He is not this and not this. Spinoza’s conception of God is reached by dropping off all determinate qualities, until the most general and most abstract term is gained. The barrenness of this logical conception, its absolute emptiness and abstractness, makes all description of it impossible. God is a bloodless entity, an absolute logical necessity and the most abstract universal. Outside of Him falls all that we call life. If this is God’s character, is He everything or nothing? If the process of abstraction rises so far above every limitation to an _ens realissimum et generalissimum_,――to the most real and most general entity,――if all content falls away from God, what does such an empty form amount to? The paradox in Spinoza’s philosophy appears here as in the case of all mysticism――for the mystic revels in paradoxes. This empty generality is all that really is. God is everything, and Spinoza points out empirical proof of this by insisting that the transitory life of man has its only meaning in such a substance. God is not this particular thing nor again that finite determination, but He is all these. He is the timeless reality of the temporal world, the infinity of finite things, the necessity of contingent nature. When therefore Spinoza speaks of God as having an intellectual love for Himself, and when he says that the attributes of thought and extension constitute the essence of the substance, he is not giving finite characteristics to God. He is struggling with language to express the inherent paradox of his philosophy.

Moreover, the delineation of the finite world with God as a background, as it appears from the point of view of a human being, is an inadequate presentation of Spinoza’s profound conception of God. For the substance is not merely a neutral point nor the central point of the universe. The substance is all. All things have neither their explanation nor their existence in themselves. God alone has an existence that explains itself, and He is the reality and essence of all finite things. God is immanent in the world. Just as the sides of a triangle get their meaning from the triangle itself, so the significance of the attributes and modes of the substance lies in the substance.

The unity of Spinoza’s God is further suggested by the relation of the attributes of thought and extension, however separate they must appear in their quality and causal dependence. Both are aspects of the same substance, in the one case in the form of extension, and in the other in the form of thought. In the all-inclusive nature of God, presumably each moment has an infinite number of correlative moments corresponding to the infinite number of the attributes of God. Since to human beings only two of these worlds lie in sight, only two corresponding modes appear, but always two. This correspondence of the physical and psychical throughout nature is called in later times _panpsychism_; in the relation of the body and mind of a human being it is called _psycho-physical parallelism_. This correspondence helped Spinoza to solve the apparent dualism of the two worlds. While ideas are determined only by ideas, and motions by motions, both series point below to the divine substance which is the significance of both. They are like the top and bottom sides of a piece of paper, neither side constituting the piece of paper, but both being necessary to it. The substance is immanent in thought as well as in extension. Both thought and extension are aspects of God. The relation of thought and extension through the Deity discloses the monistic character of Spinoza’s philosophy and seems to prove that he cannot be a materialist, although some critics have said that he is. The same reality is seen, now as consciousness and now as extension.

=Spinoza’s Doctrine of Salvation.= Spinoza divided his _Ethics_ into five parts. The first is a treatment of the nature of God; the second, of the nature and origin of the mind; the third, of the emotions; the fourth, of human bondage; the fifth, of human freedom. This most important writing of Spinoza, the only treatise on metaphysics which has been called Ethics, is a practical philosophy of life and redemption. The divisions of it, as they appear above, show that the philosophy of life is looked at from two points of view: with reference to the nature of God, and with reference to the nature of man. We have above discussed the first point,――Spinoza’s conception of God, whom he regards as pantheistic and mystic. But Spinoza’s conception of the nature of the human being in relation to such a God is the other pole of this subject. The problem of life from the human point of view involves primarily the question of human freedom. Human freedom and human bondage are conditions that depend upon the human as well as the divine nature. By Spinoza’s eliminating the human element from the nature of God, man himself has been reduced by Spinoza to an insignificant detail in a machine-like universe. Yet for man in his littleness Spinoza hews out a way to God in His greatness by his mystic reconstruction of the universe. Existence in Spinoza’s pantheistic mysticism is, after all, a sphere of wonderful grandeur for man,――more wonderful and of wider utility than the existence which man is ordinarily supposed to possess. Since God is the reality of everything, man is deified; even the loss of man’s essential humanity is the apotheosis of man.

Human salvation and freedom consist in being like God; bondage consists in being unlike Him, in mistaking the unreality of life for His reality. We are endowed with the ability of forming an adequate idea of God by means of our reason, but we are also endowed with the faculties of sensation, emotion, and imagination. The latter faculties make man a passive creature, for they bring him into dependence upon the things that act upon him and into bondage to them. We are passive when our activities are limited by such limited objects. While a passion seems to be the most active and turbulent of our faculties, if we look at it more closely, we find that instead of being active ourselves during a passion, we are being acted upon by an external object. Only as we are purely rational,――only through the reason,――are we purely active. It is then that we are like God, free like Him, and then do we rise from insignificance to greatness. Then we transcend our false ideas of freedom and become necessary beings, for in God freedom is necessity.

To be free from the passions and the finite things of the world we must understand their nature; for to understand a thing is to be delivered from it. An illusion is not an illusion when we know it to be such. To see that all the passions, sensations, imaginations, and all the other modes of thought are human limitations, is to dwell within the reason. Spinoza’s freedom is not, as will be seen, freedom in the ordinary psychological meaning of the term, but is the metaphysical freedom of being identical with the deity and determined by no finite thing. Freedom is rational knowledge. Nevertheless, freedom is ethical also, for it consists in overcoming the passions by reason. Freedom, therefore, has two sides: an escape from the emotions and an escape from obscure ideas――the goal in both cases being the life of reason. To attain freedom is to see the world as God sees it, which is the same as the reason sees it. This is to see each finite thing as eternal. Any concrete thing may be regarded by the human being as a finite and isolated thing out of all relation to other objects; or the same thing may be regarded as a detail of infinity. Looked at by itself, a thing is seen partially and falsely, for no finite thing has its explanation in itself. It is, however, seen truly when it is regarded, to use Spinoza’s own celebrated phrase, “under a certain form of eternity” (_sub specie aeternitatis_). This conception of eternity is one of the most admirable in Spinoza’s teaching. When man rises through the reason to the consciousness of the eternity of the truth of a thing, the thing itself is transformed, and the man himself has gained salvation. Any circle that I may draw is imperfect, every leaf upon the forest trees is defective, all moral activities are wanting, if regarded in their time-limitations. But below all the imperfections of the universe is its absolute mathematical perfectness. There is nothing so abortive and evil that it does not have its aspect of eternity. Side by side with Spinoza’s conception of infinity is his conception of eternity. Infinity is everlastingness, eternity is quality of being. Eternity has no reference to time. One minute may be eternal. The infinity of the substance is one aspect; the eternity of the substance is another. That eternity gained through the reason is salvation and immortality. God is reason, and by the act of the reason do we become one with Him. Our knowledge is, therefore, the measure of our morality. Knowledge and morality are the same; and whatever increases our understanding is morally good; whatever diminishes our understanding is morally wrong.

Nevertheless, from the point of view of the philosopher, there is nothing in the world that is morally good or bad,――nothing which merits his hatred, love, fear, contempt, or pity,――since all that occurs is necessary. The philosopher’s knowledge of the determinism of the world lifts him above the usually conceived world of finite things to this mystic world, reconstructed by his intellectual love of nature or God. Love for God will give to everything its proper value. It is the highest form of human activity. Love for God is an absolutely disinterested feeling, and is not therefore like human love, which is the passing from a less state to a greater. Love for God is peace, resignation, and contentment, for it is oneness with God. In fact, the love of man for God is the love of God for man; it is the love of God for Himself, since man cannot love God without becoming God. Thus man intellectually recognizes his oneness with God, and rejoices. Immortality is absorption in the eternal and necessary substance of the world. It is a common misconception that immortality is duration after death; immortality consists in looking at things under the aspect of eternity. The finite man perishes, but man’s real self, which is God, survives.

=Summary of Spinoza’s Teaching.= The rationalism of Spinoza is the final word of scholastic realism. It is a mathematical scholasticism in which the attempt is to make clear by the method of deduction all metaphysical problems. That the philosophical teaching of Spinoza is inspiring and ennobling, no one will gainsay. That his philosophy is not clear, is also true. In the beginning of his discussion, spirit is subordinated to nature; at the end, nature is subordinated to spirit. The result is that under the hands of Spinoza God has become a pure abstraction and without content, the world is an illusion, dualism is superseded by a monistic parallelism, individual activity gives way and becomes a pantheistic determinism. Yet amid all this a reconstructed world arises in which man is recompensed for all his losses by his participation in _infinity_ and _eternity_.

=Leibnitz[33] as the Finisher of the Renaissance and the Forerunner of the Enlightenment.= Leibnitz is the last of the remarkable group of Rationalists of the Renaissance, who so fully represent the spirit of its Natural Science epoch. But Leibnitz also carries us into the next period of modern philosophy――the Enlightenment. He is the transition philosopher. If the reader will examine the dates of his life, he will observe that Leibnitz lived until twenty-five years after the Enlightenment was ushered in by Locke’s _Essay on the Human Understanding_ (1690). But as Leibnitz had already formed his own philosophy by the year 1686, even so versatile a mind as his could not then renounce the Rationalistic point of view for a new one. Some of his writings, such as his _Correspondence with Clark and Bayle_, his _Theodicy_, and his _New Essays_, show that he participated in the new movement of the next period. Yet the majority of his philosophical writings show him to be a Rationalist. Although he may be called the “father of the Enlightenment,” the body of his thought belongs to the Renaissance. His main motive was that which animated all Rationalists――of stating theology in scientific terms. The immediate occasion for his doing this was the political necessity of peace among the religious bodies of Germany.

The effort of Leibnitz to restore the individual to his central place in the universe was a _secondary motive_. It nevertheless makes him the forerunner of the Enlightenment. Of the Rationalists, Leibnitz speaks for the future, just as Spinoza for the past. Leibnitz unites the Renaissance and the Enlightenment, just as Spinoza joins the Renaissance and the Middle Ages. Spinoza is the Rationalist who utters the final word of scholastic realism, while Leibnitz presages the coming individualism. Spinoza’s philosophy is science buried in traditionalism; Leibnitz’s is science breaking through traditionalism. Spinoza harks back to universals and particulars, substance and forms; Leibnitz points forward to vortex rings, energy, and dynamics. From Leibnitz’s original purpose to rationalize theology, and to succeed where Descartes and Spinoza had failed, there emerges a new motive. He no longer lays the emphasis entirely upon the universal, but he shifts it in part to the particular. The pantheism of Spinoza had systematized the individual out of its reality. Leibnitz’s conception of the individual as dynamic and his conception of the importance of the infinitesimal redeem the individual and bring Leibnitz into more modern times. To classify Leibnitz as a Rationalist is, therefore, not to describe him fully.

=The Life and Writings of Leibnitz= (1646–1716). Compared with Descartes and Spinoza, Leibnitz had a life that was long in time and rich in experience. Descartes died at 54 and Spinoza at 45, while Leibnitz lived to be 70. In striking contrast with Spinoza’s career, there was no time in the life of Leibnitz after his graduation from the university that he was not in public service. He held the offices that would naturally go to the hanger-on of princes――some of them grandiose ones. While theoretically the interests of the three Rationalists were the same, Leibnitz differed from his predecessors in that his study of philosophical problems always grew out of some practical problem or political occasion. Leibnitz was not an academic thinker, and his “writings were called forth to estimate some recent book, to outline the system for the use of a friend, to meet some special difficulty, or to answer some definite criticism.” Philosophy was only one of the interests of Leibnitz. He was jurist, historian, diplomat, mathematician, physical scientist, theologian, and philologist. Leibnitz was as much at home with the theories of Plato and Aristotle of ancient time, with those of St. Thomas and Duns Scotus of mediæval time, as with the science of Descartes and Galileo. He was precocious, had a prodigious memory and a reactive mind. In the wealth of his information and the productiveness of his genius, he stands with Aristotle as unequaled. Descartes, Spinoza, and Leibnitz belonged to the inner circle of scholars of the time, but Leibnitz was also in personal touch with political affairs and in intimate acquaintance with many of the important rulers. He was in the service of the Elector of Mainz and later of George I of England when George was only Elector of Hanover. He was distinguished by Peter the Great of Russia and Ernst August, Emperor of Germany. He corresponded with Eugene of Savoy and he was ambassador to Louis XIV of France. Sophie Charlotte of Hanover, who married the King of Prussia, was especially interested in him, and he wrote for her his _Theodicy_. The three great Rationalists came from different strata of society. Descartes was a nobleman’s son, and he voluntarily relinquished the life that Leibnitz was ambitious to enjoy. Spinoza came from the lower class. Leibnitz was the son of a college professor and belonged to the upper middle class. The ambitions of Leibnitz reached for large ends, as often happens among educated people in the middle walks of life. Among other things, he tried to reconcile the Catholics and Protestants, and he tried to universalize language by getting universal characters for all languages.

The literary production of Leibnitz was enormous, consisting of some lengthy works, but mainly of correspondence (at one time with a thousand persons) and of dissertations to learned journals and societies. No one book contains his philosophy――the _Monadology_ coming the nearest to doing so. His most considerable work is his _Theodicy_. He himself published in book form only two works: his university dissertation on _Individuation_ and the _Theodicy_.[34]

In spite of his many successes, the life of Leibnitz was not happy. From death or other causes his noble patrons changed, until he was left without a patron. His life went from bad to worse, and his death occurred almost unnoticed.

The seventy years of Leibnitz’s life fall into four periods. That he passed through three of these periods by the time he was thirty shows the voracity and versatility of his mental powers during their formative and acquisitive state. It also reveals the unusual length of his productive period,――from his thirtieth to his seventieth year. Ten years after his productive period began, when he was forty, he had completed his philosophical theory, so that the last thirty years of his life were free for its elaboration and elucidation, and in part for his departure from it. The details of Leibnitz’s life are as follows:――

1. _Leipsic and University Life_ (1646–1666).

Leibnitz was the son of a professor of the University of Leipsic. He entered the University at the age of fifteen; received his bachelor’s degree at seventeen, and his doctor’s degree at Altdorf at the age of twenty. He was offered a professorship on account of his thesis, but he declined. He published as his bachelor’s thesis, _The Principle of Individuation_ (1663).

2. _Mainz and Diplomacy_ (1666–1672).

Meeting Baron John of Boineburg, who became his patron, Leibnitz went with him to Mainz, and entered the service of the Elector of Mainz. At this time Leibnitz wrote many pamphlets at the Elector’s request, on the religious and political questions of the day. He wrote _A New Physical Hypothesis_ in 1671.

3. _Paris and Science_ (1672–1676).

Leibnitz began this period with a diplomatic mission to the court of Louis XIV in 1672; but during the year both Boineburg and the Elector died, and Mainz was no longer his home nor diplomacy his interest.

He remained in Paris (and London) three years longer, and spent the time in acquiring the “new science.” In Paris he met Arnauld the Cartesian, Tschirnhausen the German mathematician, logician, and most discriminating critic of Spinoza, and he studied with Huyghens the Dutch mathematician. In London he met Boyle, the chemist, Oldenburg, secretary of the Academy of Science, Collins, the mathematician, and he corresponded with Newton. On his return to Hanover he called on Spinoza, who showed him the manuscript of the _Ethics_.

4. _Hanover and Philosophy_ (1676–1716).

Leibnitz became court councilor and librarian to the Duke of Hanover (Brunswick-Lüneburg). He was involved in a multitude of administrative, historical, and political tasks, and he carried on an enormous correspondence. Among other things he wrote the history of the reigning family, which necessitated his going to Rome and Vienna. In 1684 he published his discovery of the differential calculus, over which arose the celebrated controversy as to whether he or Newton made the prior discovery. In 1686, in his fortieth year, he constructed his philosophical system. However, he showed his affiliation to the coming age by introducing into his system in 1697 the term “monad.” _Nearly all his important works were produced in this period._ In 1700 he founded the Academy of Sciences in Berlin. He was instrumental in the founding of an academy at St. Petersburg, and he planned academies at Dresden and Vienna.

=The Three Influences upon the Thought of Leibnitz.=

(1) _His Early Classical Studies._ The father of Leibnitz, who was a professor of moral philosophy at Leipsic, died when his son was young. Left much to himself, the boy spent his time in his father’s library. At eight years he had acquired Latin; at twelve he had read Seneca, Pliny, Quintilian, Herodotus, Xenophon, Cicero, Plato, the Roman historians, the Greek and Latin fathers. He became so absorbed in scholastic studies that his friends feared that he would not leave them, “not knowing that my mind could not be satisfied with only one kind of thing.” There can be no question that this scholastic training gave him a first hand and sympathetic appreciation of scholastic philosophy. The Aristotelian conception of cosmic purpose, which he got at this time, never left him. Among the writers of the Natural Science Period he alone returned to Aristotle. He made Aristotle’s teleological cause an integral part of his doctrine. His motto finally became, in his _Theodicy_, “Everything is best in this best of possible worlds.” While for a time he turned from Aristotle to Descartes, in his final construction of his theory he borrowed more from Aristotle.

(2) _The New Science and His Own Discoveries._ Leibnitz was more fortunate than many of his contemporaries in that his university had already included in its curriculum the study of mathematics. At the age of fifteen he was devoting himself to mathematics at Jena, and he said that the study of Kepler, Galileo, and Descartes made him feel as though “transported into a different world.” Later in life he said of himself, that at fifteen he had decided to give up the scholastic theory of Forms for the mathematical explanation of the world. He became acquainted with the theories of Hobbes and Gassendi in 1670, when he was at Mainz. In 1672, at the age of twenty-six, when he was in Paris, he made himself possessor of all that the celebrated circle of Parisian scientists had to teach. He had gone to Paris a dualist; he returned to his native land with the Aristotelian teleology side by side in his mind with the Spinozistic conception of identity and necessity, the Spinozistic method, and the mathematical theory of the significance of infinitely small particles. The next ten years (1676–1686) were spent in overcoming his own dualism by systematizing these new theories acquired from so many sources. In 1680 he had universalized the concept of force so as to apply it to both souls and bodies. In 1684 he published his discovery of the differential calculus, in which he has had to share honors with Newton. In 1685 he asserted that the centres of force have individuality. He was led to this conclusion on account of the discovery of small organisms by the microscopes of Swammerdam and ♦Leeuwenhoek. In 1686 he successfully organized his collected material into his final system, although it was not until eleven years later (1697) that he called these centres “monads.” Probably he got the term “monad” not from Bruno, but from the mystic chemist, Van Helmont.

Not only the content, but the form of his philosophy was determined by his mathematical studies. His philosophical diction is remarkably lucid. Mathematics reinforced his early resolve “in words to attain clearness and in matter usefulness.” His later discussions contain many terms that he had borrowed directly from mathematics.

(3) _Political Pressure for Religious Reconciliation._ When Frederick the Wise of Saxony in 1519 refused the crown of Emperor, Germany was thrown into internal strife that in one hundred and thirty years destroyed all its material wealth and depopulated the country. This terminated in the Thirty Years’ War (1618–1648) and the Peace of Westphalia. Leibnitz was born two years before peace was declared. He was the first German scientist in two hundred years. Both Catholics and Protestants were weary of strife, and there was a general movement toward religious reconciliation. Thus religious amity was the most urgent public question.

Pietism had been one of the movements in Germany during the recovery of the country from the Thirty Years’ War, and it represented the best side of German civilization at that time. It was a reaction on the one side against the mechanical theory of the scientists, and on the other against the destructive strife of the old and new confessions. The mother of Leibnitz was not only a Protestant, but also a Pietist, so that the subject of religion early formed an important part of her son’s training. When he entered the diplomatic service of the Elector of Mainz the question of religious reconciliation took practical form for him. No doubt his philosophy as a theory of reconciliation grew out of such practical issues, as they were presented to him at Mainz. Leibnitz had, therefore, a part in the religious reaction in Germany in the last of the seventeenth century, which aimed to reconcile the divergent interests of religion and science. He tried to effect this in no external way, by patching together irreconcilable elements, but in an internal way, by an examination of fundamental principles. With his early training, his theological reading, and his wide public experience, Leibnitz was fitted to take a prominent part in the movement for reconciliation.

=The Method of Leibnitz.= Although the philosophers who immediately followed Spinoza did not dare to accept his philosophical conclusions, they adopted his method. They united it with the syllogistic processes of formal logic for the deduction of all knowledge. This method became very prevalent, as is seen in the practices of the German Cartesians and in the preparation of academic text-books. Examples of this are Jung, Weigel, who was Leibnitz’s teacher, and Puffendorf, who tried to deduce by the geometrical method the entire system of natural right from a single principle of human need. In the next century Wolff used this method in writing his Latin text-books.

When this aspect of Spinoza’s teaching was gaining a foothold in Germany, Leibnitz came into sympathy with it through his teacher, Weigel, and at first was one of its most ardent supporters. In jest he showed by this geometrical, syllogistic method in sixty propositions that the Count Palatine of Neuberg _must_ be elected King of the Poles. In seriousness he believed that all philosophical controversies would cease when philosophy should be stated like a mathematical calculation.

Hobbes’s theory of words as counters to be used in conceptual reckoning, the universal formulas of the Art of Lull and the pains which Bruno had taken for its improvement, the Cartesian belief that the geometrical method would prove to be an art of invention――all these were influences upon Leibnitz, that committed him to the method of Spinoza and made him pursue that method energetically. Leibnitz was part of the widespread movement of the time to form a _Lingua Adamica_――a universal language, which should discover fundamental philosophical conceptions and the logical operations of their combinations. In brief, Leibnitz hoped to form a philosophical calculus.

What, asked Leibnitz, are the highest truths which in their combination yield all knowledge? What are the truths, so immediately and intuitively certain, that they force themselves upon the mind as self-evident and thereby form the ground for the deduction of all knowledge? They are of two classes: (1) The universal truths of the reason, and (2) The facts of experience. The truths of the reason are forever true; the facts of experience have a truth for that single instance. But both are true in themselves and not from deduction from anything else. They are “first truths,” for a thing is true if it can be deduced from the reason or tested as an experienced fact. The two kinds of truth are the rational or _a priori_, and the empirical or _a posteriori_. The difference between the starting point of the Rationalism of Leibnitz and the Enlightenment of Locke appears here. Locke said, “There is nothing in the mind that does not come from the senses.” “Except the mind itself and its operations,” added Leibnitz in comment.

But there is a difference between these two kinds of truth. The truths of the reason are clear and distinct; the truths of experience are clear but not distinct. Leibnitz is, be it observed, making a distinction between the two terms of the pet phrase of the Rationalists――“clear and distinct ideas.” He means that rational truth is so transparent that it is impossible to conceive its opposite; that empirical truth is only clear, and its opposite is thinkable. It is impossible to think that the three angles of a triangle equal anything but two right angles, but it is possible to think that its side, which is now two inches, may be four inches. Thus emerge the two logical principles upon which Leibnitz founded his philosophy: rational truths depend upon the _Principle of Contradiction_; empirical truths depend upon the _Principle of Sufficient Reason_. At first Leibnitz conceived that this distinction between truths did not apply to God, but only to man. Man must rejoice in the few rational truths in his possession and be content with merely establishing the actuality of his experiences. The divine reason can, however, see the impossibility of the opposite both in rational and in empirical truth. Later on Leibnitz conceived the distinction between the two kinds of truth to be absolute. That is, in the nature of things the two truths differ. The rational truth has no opposite, but is a _necessary_ truth; the empirical truth has an opposite, and is a _contingent_ truth.

Leibnitz thus shows the fundamental principles upon which knowledge is based, but what does he say about the logical method of their combination? Nothing. No one would ever suspect from Leibnitz’s philosophical remains that he had planned a system of philosophy according to the method of Spinoza. The many pamphlets of Leibnitz on many scattered subjects show how far short he fell of his ideal of a universal philosophical calculus. He was too versatile, his interests were too diversified, to carry through so slow and plodding a task. He merely stated the principles upon which a systematic symbolic philosophy might rest, without developing these principles in a logical way. Like Bacon, Leibnitz conceived a method that was more of a hope than an accomplishment.

=The Immediate Problem for Leibnitz.= Perhaps Leibnitz was called away from this purely theoretical problem of method by the practical problem of reconciling science and religion, which problem in his day had become particularly acute. For science had made rapid strides since the days of Descartes, had drawn very far away from religion, and Leibnitz’s attempt to reconcile science and religion was much more difficult than that of the preceding Rationalists. Leibnitz had accepted the most radical results of science, but he saw that science had yielded only a mechanical view of the world. Politics demanded in the exigencies of that hour some principle of unity. He sought to find some philosophical principle for the _living, religious character_ of the universe, and a principle that at the same time would preserve the results of science. He therefore sought to leave the conception of mechanical nature intact and go behind it for a teleological principle. He examined the mechanical principles of the science of his day and found them embedded in a deeper metaphysical principle.

=The Result of Leibnitz’s Examination of the Principles of Science[35]――A Plurality of Metaphysical Substances.= What was the developed scientific principle of Leibnitz’s time? And what was the result of his analysis of it? The principle was the mathematical principle of Galileo in more complex form, for there had been added to it since Galileo’s day the concept of the atom. That is to say, the fundamental scientific principle was that nature consists of the measurable movements of atoms. From his analysis of this, Leibnitz obtained as follows his conception of a plural number of substances, which he called monads.

1. Leibnitz first scrutinized the scientific conception of motion. His analysis of motion into infinitely small impulses by the method employed by Galileo, Huyghens, and Newton had already led him to one important discovery――the differential calculus. Now he scrutinizes it further and discovers that the fundamental ground of motion is _force_. While Leibnitz was in entire agreement with other scientists in their effort to reduce all phenomena to motion, he insisted that motion was not by any means the fundamental thing. He calls the Cartesian conception of motion the antechamber of true philosophy. There is no absolute motion nor absolute rest. Motion and rest are relative to each other. Descartes’ theory that there is conservation of motion is incorrect. Motion and rest are the phenomenal changes of force. Force alone is constant and conserved. Physics points beneath itself to metaphysics; motion points to force. Force is what is fundamental in nature. Force is “that which in the present state of things brings about a change in the future.” Therefore force as the substance of nature is super-spatial and immaterial, and therefore the basis of the new physics ought to be dynamic metaphysical substance.

2. Leibnitz next examined the scientific conception of the atom. Gassendi, one of that celebrated group of Parisian scientists, had been the author of the introduction of Greek atomism into modern thought. It had been generally accepted by scientists and combined with the mathematical hypothesis of Galileo. Leibnitz had known Gassendi in Paris, and he took the hard, inelastic atoms of Gassendi under examination. He agreed that the atomist was perfectly correct in saying that material bodies consist of simple parts or atoms. But Leibnitz insisted that the atomist erred in thinking such simple parts to be physical. However simple the parts might physically appear to be, they were not really simple. However small a bit of matter may be, it may be divided again, and the dividing process may go on to infinity. The atom is the extended, and the extended cannot be simple or real. Substance must be unextended, and the materialists were wrong in attributing substance to the extended. Is there anything simple that has a qualitative character? Is there anything real below the physical atoms? Yes, the metaphysical atoms. The indivisible, immaterial unit lies beneath the physical atom, and in order to reach it we must pass beneath the physical into the metaphysical. This immaterial or metaphysical atom is called by Leibnitz the _monad_; and thus is Leibnitz’s theory called _monadology_.

There are three kinds of points, or units, or “simples.” There is the mathematical point, which is simple enough, but it is only imaginary. There is the physical point, or atom, which is real but not simple. There is, lastly, the metaphysical point, or monad, which is both real and simple. The metaphysical point is the only true point. To call the material atoms real, only shows “the feebleness of the imagination, which is glad to rest, and is, therefore, in haste to make an end of division and analysis.”

3. Leibnitz then identified force, as the substance of motion, with the metaphysical atom, as the substance of the material atom. The result was the monad, as he conceived it. The monads are the principles of active working. They are the super-spatial and immaterial principles in which the mechanical principles of the universe have their roots and meaning. Nature is not dead; it is not merely extended. It is alive, resistant, and reproductive. If, as Spinoza taught, there were only one substance, nature would be non-resistant and passive. But as a matter of fact there are many substances acting for themselves, many bodies resisting other bodies. They are the centres of separate activity, and there are as many forces as there are things. There is no body without movement, no movement without force. Thus does Leibnitz reintroduce vitalism in a maturer form than is seen in neo-Platonism. Life becomes the principle of nature. Purpose is placed at the centre of things.

=The Double Nature of the Monads.= The student will find that the philosophy of Leibnitz is spoken of as a pluralism, but the student will also find that Leibnitz devoted nearly all his strength to prove that the world is after all a unity. Leibnitz analyzed the world into a plural number of parts, and the question then with him was, how to put these parts together again in an organic unity. This accomplishment would depend a good deal upon his conception of the nature of the parts.

The monads have a double character. Leibnitz conceived the monad (1) as a force centre and (2) as an immaterial soul. This makes an equivalence of psychical and physical attributes which reminds us of the Stoics’ “fiery reason” of God. The word “force,” as Leibnitz uses it, squints both toward physics and toward psychology. But such ambiguity about the monads, the cornerstones in Leibnitz’s philosophy, assists Leibnitz’s reconciliation at the start. Here, in a miniature, the physical and spiritual lie in unity. The monad is conceived as a _soul-atom_.

Leibnitz came to philosophy with a mind saturated with the mathematical ideas of the continuous, the infinitesimal, and the possible. He thought of the monads as potentialities or possibilities. He looked upon the world as essentially a developing world. Behind the facts that seem to us inflexible, lies the great world of generating force. Explanation of the actual can be made only in view of what the actual may be and has been. Let us enlarge the scope of man by so widening his conception of the actual that it will include the possible. Leibnitz also spoke of the monads as infinitesimal. He thereby lifted the conception of the infinitesimal from the realm of mathematics into that of metaphysics, just as Hobbes universalized the conception of mechanics by lifting it to metaphysics. Leibnitz, therefore, did not regard the limits of perception as the limits of nature: the reality of a nature object must be too small to be the object of perception. In the same way he made use of his mathematical conception of continuity. Leibnitz’s conception of nature-continuity is one of his contributions to philosophy. Within itself the world of nature consists of a continuous gradation from the lower to the higher forms; and also the world of nature is continuous with the world of the spirit. There are no leaps in the series from matter to God. Seeming differences in kind are only differences in degree; for example, evil is only the absence of good; matter is only an obscure idea of spirit.

But this Leibnitzian atomism consists of soul-atoms. These monads, these force-centres are souls, and the mathematical qualities have a place in Leibnitz’s description of the psychical powers of the monad. The monad is a soul, for soul is the only substance in the universe that may pass through many changes and it, itself, not change. The self is the only subject of which many predicates may be asserted, while it, itself, may not be the predicate of any other subject. The idea of myself underlies all my mental states. The monad is an entelechy, or an entity having its purpose within itself. All its attributes are contained within itself, and it is, therefore, by nature, sufficient unto itself. It is an individual which passes from one state to another, moved by its “constitutional appetition.”

Among the psychical powers none is more important in Leibnitz’s description of the monad than its power of representation. Representation is the general function of the monad――from the lowest to the highest monad. This means that each monad is the world force, yet in a particular form,――a world substance, but in some peculiar aspect. Every monad is a microcosm. Each represents the world so far as it is conscious of its own activity. But it is evident that all things in the universe are not conscious, and therefore all soul-monads are not conscious. In souls there are, therefore, more than conscious thoughts――there are thoughts that are unconscious. Among the Rationalists Leibnitz is the first to give significance to the so-called unconscious states that form so important a place in modern psychology. (But see Plotinus.) As a wave is composed of small particles of water, so the mind is made up of a myriad of unconscious states. The conscious state is the general effect of the whole. A soul-monad contains in itself at all times representations of the whole world, some obscure, some clear. This power of universal representation makes the monad a microcosm. What we call knowledge of the external world is our representation of it within ourselves. This representation is possible to us because we reproduce it in miniature. Since the monad directly perceives only itself and its own states, it follows that the more clearly and distinctly it is conscious of its own activities, the more adequately does it represent the cosmos. The converse is also true――that the more a monad represents the cosmos, the more truly does it represent itself.

In his development of his description of the monad, Leibnitz hits upon two catch-phrases, one of which presents his doctrine of the physical isolation of the monad, the other presents the doctrine of its ideal psychical unity. These phrases are: “the monads are windowless” and “the monads mirror the universe.” By “windowless” Leibnitz means that each monad is “like a separate world, self-sufficient, independent of every other creature.” “Having no windows by which anything can enter or depart,” the monad can perceive only its own states. Whatever happens to it comes from itself alone as a purely internal principle. The monad’s development is self-development and not the result of external changes. Nevertheless the monad is a “mirror of the universe.” In this psychical qualification of the nature of the monad, its physical isolation vanishes and the way is open for a unity of monads, which would have otherwise seemed to be physically hopelessly sundered. How is it possible for each of the numberless monads, all so different, to “mirror the universe”? The answer is found in their psychical power of representation.

=The Two Forms of Leibnitz’s Conception of the Unity of the Substances.= The principle of unity among the monads is called by Leibnitz a _preëstablished harmony_. He presented this principle of harmony in two ways. In part the harmony comes out of their constitution, as he conceived it to be. In part Leibnitz artificially superimposed it upon the monads for theological reasons. In either case it is preëstablished.

=The Intrinsic Unity of the Monads――The Philosophical Unity.= There is a family resemblance among the monads. The lowest reproduces the universe in obscure and elementary representations. Minerals and plants are sleeping monads with entirely unconscious ideas. Animals are dreaming monads. Man is a waking monad. The highest monad is God, who reproduces the universe in clear and distinct ideas. Between God and matter there is a series of monads, graded as to the clearness of their ideas. All contain the universe by representation. All are bound together according to the principle of continuity; plants are lower animals and animals are less perfect men. Man is a monad whose conscious activity has risen to the height of self-consciousness, with the cognate power of reason. There is no inert matter; no soul-less bodies nor body-less souls. The smallest portion of dust is the habiliment of animalculæ. Nothing is dead, and nature is a gradation of monads in differing degrees of activity.

Metaphysically the monads are isolated, yet in nature as we see them, they live in groups, and compose the things which we call plants, animals, and men. An organic thing is a combination of monads with a central ruling monad. This central monad is the soul of the group; the subordinate ones form the body of the organism. The influence of the soul or ruling monad upon the body-monads is purely ideal. They all strive for the same end, which the soul represents more clearly. The group acts spontaneously and together, not from any outside influence. An inanimate object differs from such a living organism, inasmuch as it is a group of monads without a soul or a ruling, central monad; and therefore such a monad is both soul and body. There is therefore no dualism between soul and body in any creatures, for body is only obscure or unconscious activity. The body consists of monads having a confused sense of their activity.

This continuity and unity within the world, as Leibnitz sees it, is only the logical development of the unity with which he originally endowed his monads. Although he starts the monads as “windowless,” he also says that “they mirror the universe.” They are so conceived as to be originally physically separated, but psychologically and ideally united. “Their natural harmony resides in an ideal of perfect activity, while in actual existence they are independent.” The ideal which unites them is God, the last term in the graded series of the monads. He is the monad of monads, because He is perfect, conscious activity. Just as the various groups of monads are ruled by a central soul-monad, so the world of these groups is an hierarchy, which derives its unitary and harmonious character from this dominating monad. The world may be likened to a pyramid with God at the apex. The world is like a machine which differs from other machines, in that its parts are little machines. Although the parts seem to operate separately, they are under the dominating control of God. God is their intrinsic unity and the universe is a preëstablished harmony.

A comparison with Spinoza’s conception of the world of nature brings out Leibnitz’s meaning effectively. Both philosophers conceive nature phenomena to be under the law of mechanical causation. To Spinoza, however, all phenomena are qualitatively alike; there are no grades or distinctions of value between them. All are modes of substance and all illusions in the sight of God. To Spinoza phenomena are homogeneous. Leibnitz’s estimate of the world of nature is quite different, and for him nature has a far richer endowment. The phenomena of nature are not homogeneous. Their difference does not consist in their content, but in the degree in which they represent the universe. The law of nature is a unifying principle that gives unitary individuality to the members under the law. The individuality of the terms of the nature-series is implied in the very nature of the law of necessity, and on the other hand, the individual terms, for their part, transform the law of necessity into a principle of unity that is higher than bare necessity. In a necessitated series, Leibnitz points out, each term is determined by the preceding, and in turn each term determines the events that follow. Thus, while nature phenomena are a series and a necessitated series, it is a series whose existence depends upon each event having not only its place, but its unique place. No other event can fill that place, and the conditions that give the event its place constitute its individuality. Every finite event has, so to speak, its formula, and this gives individuality to each term of the series, which appeared to Spinoza only as a homogeneous, mathematical, and characterless mode. Life is meaningful to Leibnitz, because each member of the necessitated series of events has its unique part to play. The changes of life are to Spinoza void of meaning, because he conceives them to be undifferentiated. The law of mechanical necessity became under Leibnitz’s hands a principle of harmony, a teleological principle. Even in the necessitated mathematical series, such as Spinoza conceived the world to be, Leibnitz believed that necessity implies individuality and individuality implies purpose.

How vital, therefore, does life now appear, with its mechanical members transformed into living units! Universal striving or force fills nature, and the surging of individual forces gives a new meaning to the unity of the whole. The mechanical series――the physiological changes of our bodies and the efficient causes in nature――are only the expression of the inner teleological development. Leibnitz points out several pregnant principles that are aspects of this preëstablished but intrinsic harmony. In the first place, nature has no breaks and abhors a vacuum; and the series is a continuous one,――_the law of continuity_. Member follows member in continuous and graded order. Their qualitative differences are differences of quality of activity. Rest and motion, good and evil, are differences of degree. In the second place, there is nothing superfluous; no two things in nature are alike. If they were alike, they would be identical――_the law of the identity of indiscernibles_. Although there is no absolute antithesis or contrast between things, there is no absolute likeness. Every monad must be differentiated from every other intrinsically, _i. e._ according to its perfected activity. Therefore, in the third place, every member has an excuse for being――_the law of sufficient reason_. Every member has its part to perform and no other can act as an understudy for it. However insignificant any member may appear to be, it is as unique as its bigger neighbor.

=The Superimposed Unity of the Monads――The Theological Unity.= The intrinsic unity of the monads is derived naturally from the monads themselves, but it is an unattained ideal for which they strive. When Leibnitz turns his philosophy into a theodicy, or justification of the nature of God, this unity of the world takes on a different form and assumes a theological importance. The unity is no longer an intrinsic unity, with no actual but only ideal existence depending upon the highest monad in the series, but is an actual personality who exists apart from the world. The world is his eternal purpose. Probably this conception was always in the background of Leibnitz’s thought, but it cannot be deduced from his philosophy. It is a conception afterwards superimposed upon his philosophy. Leibnitz now conceives God not as an ideal goal, but as a perfect and actual person, whose reason impelled Him to construct the best possible world. The world in which we live is the world He chose. It is perfectly conceivable that the world could be different. Why, among all the possible worlds, did God choose to construct this world? There is no reason in logic, but in fact. There was no necessity for its construction. The fact is the excellence of the world. Spinoza said that all possible worlds exist. Leibnitz said this best possible world exists. Look about you; is it not so?

The best possible world is a world of free agents, whose acts are rewarded or punished according to their deserts. If we discover what seems to be inexplicable evil, we must regard it as an incident in the harmony of the whole. The world would be less good without evil. There is no more evil than there ought to be. The world which God conceived to be the best possible――this world――is a world of lights and shades. Evil comes from the free agency of man, and God is not responsible for it. It is better to have evil and free agency than no evil and no free agency. Evil after all is not positive, and is only due to the indistinct ideas of man. It is the absence of good, as cold is the absence of heat.

Thus a preëstablished harmony was constructed by Leibnitz that does not come out of his original philosophical premises. Leibnitz used his celebrated figure of the two clocks to illustrate the harmony of the monads. Two clocks keep the same time, not because they influence one another (interaction), nor because the maker moves the hands of one (Occasionalism), but because they have been thus constructed by an intelligent Creator. Thus the harmony of the world implies a personal God. Leibnitz’s philosophical Rationalism here passed into theology, and his metaphysics became an ethics. Leibnitz began with a monadology, and by means of the conception of harmony passed to an optimism.