Physics proves to us the impossibility of perpetual motion among visible, tangible bodies, at the same time that it reveals to us a world where perpetual motion is the rule—the world of molecules and atoms. In the world of gross matter, or of ponderable bodies, perpetual motion is impossible because here it takes energy, or its equivalent, to beget energy. Friction very soon turns the kinetic energy of motion into the potential energy of heat, which quickly disappears in that great sea of energy, the low uniform temperature of the earth. But when we reach the interior world of matter, the world of molecules, atoms, and electrons, we have reached a world where perpetual motion is the rule; we have reached the fountain-head of energy, and the motion of one body is not at the expense of the motion of some other body, but is a part of the spontaneous struggling and jostling and vibration that go on forever in all the matter of the universe. What is called the Brunonian movement (first discovered by the botanist Robert Brown in 1827) is within reach of the eye armed with a high-power microscope. Look into any liquid that holds in suspension very small particles of solid matter, such as dust particles in the air, or the granules of ordinary water-color paints dissolved in water: not a single one of the particles is at rest; they are all mysteriously agitated; they jump hither and thither; it is a wild chaotic whirl and dance of minute particles. Brown at first thought they were alive, but they were only non-living particles dancing to the same tune which probably sets suns and systems whirling in the heavens. Ramsay says that tobacco smoke confined in the small flat chamber formed in the slide of a microscope, shows this movement, in appearance like the flight of minute butterflies. The Brunonian movement is now believed to be due to the bombardment of the particles by the molecules of the liquid or gas in which they are suspended. The smaller the particles, the livelier they are. These particles themselves are made up of a vast number of molecules, among which the same movement or agitation, much more intense, is supposed to be taking place; the atoms which compose the molecules are dancing and frisking about like gnats in the air, and the electrons inside the atoms are still more rapidly changing places.

We meet with the same staggering figures in the science of the infinitely little that we do in the science of the infinitely vast. Thus the physicist deals with a quantity of matter a million million times smaller than can be detected in the most delicate chemical balance. Molecules inconceivably small rush about in molecular space inconceivably small. Ramsay calculates how many collisions the molecules of gas make with other molecules every second, which is four and one half quintillions. This staggers the mind like the tremendous revelations of astronomy. Mathematics has no trouble to compute the figures, but our slow, clumsy minds feel helpless before them. In every drop of water we drink, and in every mouthful of air we breathe, there is a movement and collision of particles so rapid in every second of time that it can only be expressed by four with eighteen naughts. If the movement of these particles were attended by friction, or if the energy of their impact were translated into heat, what hot mouthfuls we should have! But the heat, as well as the particles, is infinitesimal, and is not perceptible.

II

The molecules and atoms and electrons into which science resolves matter are hypothetical bodies which no human eye has ever seen, or ever can see, but they build up the solid frame of the universe. The air and the rocks are not so far apart in their constituents as they might seem to our senses. The invisible and indivisible molecules of oxygen which we breathe, and which keep our life-currents going, form about half the crust of the earth. The soft breeze that fans and refreshes us, and the rocks that crush us, are at least half-brothers. And herein we get a glimpse of the magic of chemical combinations. That mysterious property in matter which we call chemical affinity, a property beside which human affinities and passions are tame and inconstant affairs, is the architect of the universe. Certain elements attract certain other elements with a fierce and unalterable attraction, and when they unite, the resultant compound is a body totally unlike either of the constituents. Both substances have disappeared, and a new one has taken their place. This is the magic of chemical change. A physical change, as of water into ice, or into steam, is a simple matter; it is merely a matter of more or less heat; but the change of oxygen and hydrogen into water, or of chlorine gas and the mineral sodium into common salt, is a chemical change. In nature, chlorine and sodium are not found in a free or separate state; they hunted each other up long ago, and united to produce the enormous quantities of rock salt that the earth holds. One can give his imagination free range in trying to picture what takes place when two or more elements unite chemically, but probably there is no physical image that can afford even a hint of it. A snake trying to swallow himself, or two fishes swallowing each other, or two bullets meeting in the air and each going through the centre of the other, or the fourth dimension, or almost any other impossible thing, from the point of view of tangible bodies, will serve as well as anything. The atoms seem to get inside of one another, to jump down one another's throats, and to suffer a complete transformation. Yet we know that they do not; oxygen is still oxygen, and carbon still carbon, amid all the strange partnerships entered into, and all the disguises assumed. We can easily evoke hydrogen and oxygen from water, but just how their molecules unite, how they interpenetrate and are lost in one another, it is impossible for us to conceive.

We cannot visualize a chemical combination because we have no experience upon which to found it. It is so fundamentally unlike a mechanical mixture that even our imagination can give us no clew to it. It is thinkable that the particles of two or more substances however fine, mechanically mixed, could be seen and recognized if sufficiently magnified; but in a chemical combination, say like iron sulphide, no amount of magnification could reveal the two elements of iron and sulphur. They no longer exist. A third substance unlike either has taken their place.

We extract aluminum from clay, but no conceivable power of vision could reveal to us that metal in the clay. It is there only potentially. In a chemical combination the different substances interpenetrate and are lost in one another: they are not mechanically separable nor individually distinguishable. The iron in the red corpuscles of the blood is not the metal we know, but one of its many chemical disguises. Indeed it seems as if what we call the ultimate particles of matter did not belong to the visible order and hence were incapable of magnification.

That mysterious force, chemical affinity, is the true and original magic. That two substances should cleave to each other and absorb each other and produce a third totally unlike either is one of the profound mysteries of science. Of the nature of the change that takes place, I say, we can form no image. Chemical force is selective; it is not promiscuous and indiscriminate like gravity, but specific and individual. Nearly all the elements have their preferences and they will choose no other. Oxygen comes the nearest to being a free lover among the elements, but its power of choice is limited.

Science conceives of all matter as grained or discrete, like a bag of shot, or a pile of sand. Matter does not occupy space continuously, not even in the hardest substances, such as the diamond; there is space, molecular space, between the particles. A rifle bullet whizzing past is no more a continuous body than is a flock of birds wheeling and swooping in the air. Air spaces separate the birds, and molecular spaces separate the molecules of the bullet. Of course it is unthinkable that indivisible particles of matter can occupy space and have dimensions. But science goes upon this hypothesis, and the hypothesis proves itself.

After we have reached the point of the utmost divisibility of matter in the atom, we are called upon to go still further and divide the indivisible. The electrons, of which the atom is composed, are one hundred thousand times smaller, and two thousand times lighter than the smallest particle hitherto recognized, namely, the hydrogen atom. A French physicist conceives of the electrons as rushing about in the interior of the atom like swarms of gnats whirling about in the dome of a cathedral. The smallest particle of dust that we can recognize in the air is millions of times larger than the atom, and millions of millions of times larger than the electron. Yet science avers that the manifestations of energy which we call light, radiant heat, magnetism, and electricity, all come from the activities of the electrons. Sir J. J. Thomson conceives of a free electron as dashing about from one atom to another at a speed so great as to change its location forty million times a second. In the electron we have matter dematerialized; the electron is not a material particle. Hence the step to the electric constitution of matter is an easy one. In the last analysis we have pure disembodied energy. "With many of the feelings of an air-man," says Soddy, "who has left behind for the first time the solid ground beneath him," we make this plunge into the demonstrable verities of the newest physics; matter in the old sense—gross matter—fades away. To the three states in which we have always known it, the solid, the liquid, and the gaseous, we must add a fourth, the ethereal—the state of matter which Sir Oliver Lodge thinks borders on, or is identical with, what we call the spiritual, and which affords the key to all the occult phenomena of life and mind.

As we have said, no human eye has ever seen, or will see, an atom; only the mind's eye, or the imagination, sees atoms and molecules, yet the atomic theory of matter rests upon the sure foundation of experimental science. Both the chemist and the physicist are as convinced of the existence of these atoms as they are of the objects we see and touch. The theory "is a necessity to explain the experimental facts of chemical composition." "Through metaphysics first," says Soddy, "then through alchemy and chemistry, through physical and astronomical spectroscopy, lastly through radio-activity, science has slowly groped its way to the atom." The physicists make definite statements about these hypothetical bodies all based upon definite chemical phenomena. Thus Clerk Maxwell assumes that they are spherical, that the spheres are hard and elastic like billiard-balls, that they collide and glance off from one another in the same way, that is, that they collide at their surfaces and not at their centres.

Only two of our senses make us acquainted with matter in a state which may be said to approach the atomic—smell and taste. Odors are material emanations, and represent a division of matter into inconceivably small particles. What are the perfumes we smell but emanations, flying atoms or electrons, radiating in all directions, and continuing for a shorter or longer time without any appreciable diminution in bulk or weight of the substances that give them off? How many millions or trillions of times does the rose divide its heart in the perfume it sheds so freely upon the air? The odor of the musk of certain animals lingers under certain conditions for years. The imagination is baffled in trying to conceive of the number and minuteness of the particles which the fox leaves of itself in the snow where its foot was imprinted—so palpable that the scent of a hound can seize upon them hours after the fox has passed! The all but infinite divisibility of matter is proved by every odor that the breeze brings us from field and wood, and by the delicate flavors that the tongue detects in the food we eat and drink. But these emanations and solutions that affect our senses probably do not represent a chemical division of matter; when we smell an apple or a flower, we probably get a real fragment of the apple, or of the flower, and not one or more of its chemical constituents represented by atoms or electrons. A chemical analysis of odors, if it were possible, would probably show the elements in the same state of combination as the substances from which the odors emanated.

The physicists herd these ultimate particles of matter about; they have a regular circus with them; they make them go through films and screens; they guide them through openings; they count them as their tiny flash is seen on a sensitized plate; they weigh them; they reckon their velocity. The alpha-rays from radio-active substances are swarms of tiny meteors flying at the incredible speed of twelve thousand miles a second, while the meteors of the midnight sky fly at the speed of only forty miles a second. Those alpha particles are helium atoms. They are much larger than beta particles, and have less penetrative power. Sir J. J. Thomson has devised a method by which he has been able to photograph the atoms. The photographic plate upon which their flight is recorded suggests a shower of shooting stars. Oxygen is found to be made up of atoms of several different forms.

III

The "free path" of molecules, both in liquids and in gases, is so minute as to be beyond the reach of the most powerful microscope. This free path in liquids is a zigzag course, owing to the perpetual collisions with other molecules. The molecular behavior of liquids differs from that of gases only in what is called surface tension. Liquids have a skin, a peculiar stress of the surface molecules; gases do not, but tend to dissipate and fill all space. A drop of water remains intact till vaporization sets in; then it too becomes more and more diffused.

When two substances combine chemically, more or less heat is evolved. When the combination is effected slowly, as in an animal's body, heat is slowly evolved. When the combustion is rapid, as in actual fire, heat is rapidly evolved. The same phenomenon may reach the eye as light, and the hand as heat, though different senses get two different impressions of the same thing. So a mechanical disturbance may reach the ear as sound, and be so interpreted, and reach the hand as motion in matter. In combustion, the oxygen combines rapidly with the carbon, giving out heat and light and carbon dioxide, but why it does so admits of no explanation. Herein again is where life differs from fire; we can describe combustion in terms of chemistry, but after we have described life in the same terms something—and this something is the main thing—remains untouched.

The facts of radio-activity alone demonstrate the truth of the atomic theory. The beta rays, or emanations from radium, penetrating one foot of solid iron are very convincing. And this may go on for hundreds of years without any appreciable diminution of size or weight of the radio-active substance. "A gram of such substance," says Sir Oliver Lodge, "might lose a few thousand of atoms a second, and yet we could not detect the loss if we continued to weigh it for a century." The volatile essences of organic bodies which we detect in odors and flavors, are not potent like the radium emanations. We can confine them and control them, but we cannot control the rays of radio-active matter any more than we can confine a spirit. We can separate the three different kinds of rays—the alpha, the beta, and the gamma—by magnetic devices, but we cannot cork them up and isolate them, as we can musk and the attar of roses.

And these emanations are taking place more or less continuously all about us and we know it not. In fact, we are at all times subjected to a molecular bombardment of which we never dream; minute projectiles, indivisible points of matter, are shot out at us in the form of electrons from glowing metals, from lighted candles, and from other noiseless and unsuspected batteries at a speed of tens of thousands of miles a second, and we are none the wiser for it. Indeed, if we could see or feel or be made aware of it, in what a different world we should find ourselves! How many million-or billion-fold our sense of sight and touch would have to be increased to bring this about! We live in a world of collisions, disruptions, and hurtling missiles of which our senses give us not the slightest evidence, and it is well that they do not. There is a tremendous activity in the air we breathe, in the water we drink, in the food we eat, and in the soil we walk upon, which, if magnified till our senses could take it in, would probably drive us mad. It is in this interior world of molecular activity, this world of electric vibrations and oscillations, that the many transformations of energy take place. This is the hiding-place of the lightning, of the electrons which moulded together make the thunderbolt. What an underworld of mystery and power it is! In it slumbers all the might and menace of the storm, the power that rends the earth and shakes the heavens. With the mind's eye one can see the indivisible atoms giving up their electrons, see the invisible hosts, in numbers beyond the power of mathematics to compute, being summoned and marshalled by some mysterious commander and hurled in terrible fiery phalanxes across the battlefield of the storm.

The physicist describes the atom and talks about it as if it were "a tangible body which one could hold in his hand like a baseball." "An atom," Sir Oliver Lodge says, "consists of a globular mass of positive electricity with minute negative electrons embedded in it." He speaks of the spherical form of the atom, and of its outer surface, of its centre, and of its passing through other atoms, and of the electrons that revolve around its centre as planets around a sun. The electron, one hundred thousand times smaller than an atom, yet has surface, and that surface is a dimpled and corrugated sheet—like the cover of a mattress. What a flight of the scientific imagination is that!

The disproportion between the size of an atom and the size of an electron is vastly greater than that between the sun and the earth. Represent an atom, says Sir Oliver Lodge, by a church one hundred and sixty feet long, eighty feet broad, and forty feet high; the electrons are like gnats inside it. Yet on the electric theory of matter, electrons are all of the atom there is; there is no church, but only the gnats rushing about. We know of nothing so empty and hollow, so near a vacuum, as matter in this conception of it. Indeed, in the new physics, matter is only a hole in the ether. Hence the newspaper joke about the bank sliding down and leaving the woodchuck-hole sticking out, looks like pretty good physics. The electrons give matter its inertia, and give it the force we call cohesion, give it its toughness, its strength, and all its other properties. They make water wet, and the diamond hard. They are the fountain-head of the immense stores of the inter-atomic energy, which, if it could be tapped and controlled, would so easily do all the work of the world. But this we cannot do. "We are no more competent," says Professor Soddy, "to make use of these supplies of atomic energy than a savage, ignorant of how to kindle a fire, could make use of a steam-engine." The natural rate of flow of this energy from its atomic sources we get as heat, and it suffices to keep life going upon this planet. It is the source of all the activity we see upon the globe. Its results, in the geologic ages, are stored up for us in coal and oil and natural gas, and, in our day, are available in the winds, the tides, and the waterfalls, and in electricity.

IV

The electric constitution of matter is quite beyond anything we can imagine. The atoms are little worlds by themselves, and the whole mystery of life and death is in their keeping. The whole difference in the types of mind and character among men is supposed to be in their keeping. The different qualities and properties of bodies are in their keeping. Whether an object is hot or cold to our senses, depends upon the character of their vibrations; whether it be sweet or sour, poisonous or innocuous to us, depends upon how the atoms select their partners in the whirl and dance of their activities. The hardness and brilliancy of the diamond is supposed to depend upon how the atoms of carbon unite and join hands.

I have heard the view expressed that all matter, as such, is dead matter, that the molecules of hydrogen, oxygen, carbon, nitrogen, iron, phosphorus, calcium, and so on, in a living body, are themselves no more alive than the same molecules in inorganic matter. Nearly nine tenths of a living body is water; is not this water the same as the water we get at the spring or the brook? is it any more alive? does water undergo any chemical change in the body? is it anything more than a solvent, than a current that carries the other elements to all parts of the body? There are any number of chemical changes or reactions in a living body, but are the atoms and molecules that are involved in such changes radically changed? Can oxygen be anything but oxygen, or carbon anything but carbon? Is what we call life the result of their various new combinations? Many modern biologists hold to this view. In this conception merely a change in the order of arrangement of the molecules of a substance—which follows which or which is joined to which—is fraught with consequences as great as the order in which the letters of the alphabet are arranged in words, or the words themselves are arranged in sentences. The change of one letter in a word often utterly changes the meaning of that word, and the changing of a word in the sentence may give expression to an entirely different idea. Reverse the letters in the word "God," and you get the name of our faithful friend the dog. Huxley and Tyndall both taught that it was the way that the ultimate particles of matter are compounded that makes the whole difference between a cabbage and an oak, or between a frog and a man. It is a hard proposition. We know with scientific certainty that the difference between a diamond and a piece of charcoal, or between a pearl and an oyster-shell, is the way that the particles of carbon in the one case, and of calcium carbide in the other, are arranged. We know with equal certainty that the difference between certain chemical bodies, like alcohol and ether, is the arrangement of their ultimate particles, since both have the same chemical formula. We do not spell acetic acid, alcohol, sugar, starch, animal fat, vegetable oils, glycerine, and the like, with the same letters; yet nature compounds them all of the same atoms of carbon, hydrogen, and oxygen, but in different proportions and in different orders.

Chemistry is all-potent. A mechanical mixture of two or more elements is a simple affair, but a chemical mixture introduces an element of magic. No conjurer's trick can approach such a transformation as that of oxygen and hydrogen gases into water. The miracle of turning water into wine is tame by comparison. Dip plain cotton into a mixture of nitric and sulphuric acids and let it dry, and we have that terrible explosive, guncotton. Or, take the cellulose of which cotton is composed, and add two atoms of hydrogen and one of oxygen, and we have sugar. But we are to remember that the difference here indicated is not a quantitative, but a qualitative one, not one affecting bulk, but affecting structure. Truly chemistry works wonders. Take ethyl alcohol, or ordinary spirits of wine, and add four more atoms of carbon to the carbon molecule, and we have the poison carbolic acid. Pure alcohol can be turned into a deadly poison, not by adding to, but simply by taking from it; take out one atom of carbon and two of hydrogen from the alcohol molecule, and we have the poison methyl alcohol. But we are to remember that the difference here indicated is not a quantitative, but a qualitative one, not one affecting bulk, but affecting structure.

In our atmosphere we have a mechanical mixture of nitrogen and oxygen, four parts of nitrogen to one of oxygen. By uniting the nitrogen and oxygen chemically (N{2}O) we have nitrous oxide, laughing-gas. Ordinary starch is made up of three different elements—six parts of carbon, ten parts of hydrogen, and five parts of oxygen (C{6}H{10}O{5}). Now if we add water to this compound, we have a simple mixture of starch and water, but if we bring about a chemical union with the elements of water (hydrogen and oxygen), we have grape sugar. This sugar is formed in green leaves by the agency of sunlight, and is the basis of all plant and animal food, and hence one of the most important things in nature.

Carbon is a solid, and is seen in its pure state in the diamond, the hardest body in nature and the most valued of all precious stones, but it enters largely into all living bodies and is an important constituent of all the food we eat. As a gas, united with the oxygen of the air, forming carbon dioxide, it was present at the beginning of life, and probably helped kindle the first vital spark. In the shape of wood and coal, it now warms us and makes the wheels of our material civilization go round. Diamond stuff, through the magic of chemistry, plays one of the principle roles in our physical life; we eat it, and are warmed and propelled by it, and cheered by it. Taken as carbonic acid gas into our lungs, it poisons us; taken into our stomachs, it stimulates us; dissolved in water, it disintegrates the rocks, eating out the carbonate of lime which they contain. It is one of the principal actors in the drama of organized matter.

V

We have a good illustration of the power of chemistry, and how closely it is dogging the footsteps of life, in the many organic compounds it has built up out of the elements, such as sugar, starch, indigo, camphor, rubber, and so forth, all of which used to be looked upon as impossible aside from life-processes. It is such progress as this that leads some men of science to believe that the creation of life itself is within the reach of chemistry. I do not believe that any occult or transcendental principle bars the way, but that some unknown and perhaps unknowable condition does, as mysterious and unrepeatable as that which separates our mental life from our physical. The transmutation of the physical into the psychical takes place, but the secret of it we do not know. It does not seem to fall within the law of the correlation and the conservation of energy.

Free or single atoms are very rare; they all quickly find their mates or partners. This eagerness of the elements to combine is one of the mysteries. If the world of visible matter were at one stroke resolved into its constituent atoms, it would practically disappear; we might smell it, or taste it, if we were left, but we could not see it, or feel it; the water would vanish, the solid ground would vanish—more than half of it into oxygen atoms, and the rest mainly into silicon atoms.

The atoms of different bodies are all alike, and presumably each holds the same amount of electric energy. One wonders, then, how the order in which they are arranged can affect them so widely as to produce bodies so unlike as, say, alcohol and ether. This brings before us again the mystery of chemical arrangement or combination, so different from anything we know among tangible bodies. It seems to imply that each atom has its own individuality. Mix up a lot of pebbles together, and the result would be hardly affected by the order of the arrangement, but mix up a lot of people, and the result would be greatly affected by the fact of who is elbowing who. It seems the same among the mysterious atoms, as if some complemented or stimulated those next them, or had an opposite effect. But can we think of the atoms in a chemical compound as being next one another, or merely in juxtaposition? Do we not rather have to think of them as identified with one another to an extent that has no parallel in the world of ponderable bodies? A kind of sympathy or affinity makes them one in a sense that we only see realized among living beings.

Chemical activity is the first step from physical activity to vital activity, but the last step is taken rarely—the other two are universal. Chemical changes involve the atom. What do vital changes involve? We do not know. We can easily bring about the chemical changes, but not so the vital changes. A chemical change destroys one or more substances and produces others totally unlike them; a vital change breaks up substances and builds up other bodies out of them; it results in new compounds that finally cover the earth with myriads of new and strange forms.



X

THE VITAL ORDER

I

The mechanistic theory of life—the theory that all living things can be explained and fully accounted for on purely physico-chemical principles—has many defenders in our day. The main aim of the foregoing chapters is to point out the inadequacy of this view. At the risk of wearying my reader I am going to collect under the above heading a few more considerations bearing on this point.

A thing that grows, that develops, cannot, except by very free use of language, be called a machine. We speak of the body as a machine, but we have to qualify it by prefixing the adjective living—the living machine, which takes it out of the mechanical order of things fabricated, contrived, built up from without, and puts it in the order we call vital, the order of things self-developed from within, the order of things autonomous, as contrasted with things automatic. All the mechanical principles are operative in the life processes, but they have been vitalized, not changed in any way but in the service of a new order of reality. The heart with its chambers and valves is a pump that forces the blood through the system, but a pump that works itself and does not depend upon pneumatic pressure—a pump in which vital energy takes the place of gravitational energy. The peristaltic movement in the intestines involves a mechanical principle, but it is set up by an inward stimulus, and not by outward force. It is these inward stimuli, which of course involve chemical reactions, that afford the motive power for all living bodies and that put the living in another order from the mechanical. The eye is an optical instrument,—a rather crude one, it is said,—but it cannot be separated from its function, as can a mere instrument—the eye sees as literally as the brain thinks. In breathing we unconsciously apply the principle of the bellows; it is a bellows again which works itself, but the function of which, in a very limited sense, we can inhibit and control. An artificial, or man-made, machine always implies an artificer, but the living machine is not made in any such sense; it grows, it arises out of the organizing principle that becomes active in matter under conditions that we only dimly understand, and that we cannot reproduce.

The vital and the mechanical cooeperate in all our bodily functions. Swallowing our food is a mechanical process, the digestion of it is a chemical process and the assimilation and elimination of it a vital process. Inhaling and exhaling the air is a mechanical process, the oxidation of the blood is a chemical process, and the renewal of the corpuscles is a vital process. Growth, assimilation, elimination, reproduction, metabolism, and secretion, are all vital processes which cannot be described in terms of physics and chemistry. All our bodily movements—lifting, striking, walking, running—are mechanical, but seeing, hearing, and tasting, are of another order. And that which controls, directs, cooerdinates, and inhibits our activities belongs to a still higher order, the psychic. The world of thoughts and emotions within us, while dependent upon and interacting with the physical world without us, cannot be accounted for in terms of the physical world. A living thing is more than a machine, more than a chemical laboratory.

We can analyze the processes of a tree into their mechanical and chemical elements, but there is besides a kind of force there which we must call vital. The whole growth and development of the tree, its manner of branching and gripping the soil, its fixity of species, its individuality—all imply something that does not belong to the order of the inorganic, automatic forces. In the living animal how the psychic stands related to the physical or physiological and arises out of it, science cannot tell us, but the relation must be real; only philosophy can grapple with that question. To resolve the psychic and the vital into the mechanical and chemical and refuse to see any other factors at work is the essence of materialism.

II

Any contrivance which shows an interdependence of parts, that results in unity of action, is super-mechanical. The solar system may be regarded as a unit, but it has not the purposive unity of a living body. It is one only in the sense that its separate bodies are all made of one stuff, and obey the same laws and move together in the same direction, but a living body is a unit because all its parts are in the service of one purposive end. An army is a unit, a flock of gregarious birds, a colony of ants or bees, is a unit because the spirit and purpose of one is the spirit and purpose of all; the unity is psychological.

Only living bodies are adaptive. Adaptation, of course, has its physics or its chemistry, because it is a physical phenomenon; but there is no adaptation of a rock or a clay-bank to its environment; there is only mechanical and chemical adjustment. The influence of the environment may bring about chemical and physical changes in a non-living body, but they are not purposive as in a living body. The fat in the seeds of plants in northern countries is liquid and solid at a lower temperature than in tropical climates. Living organisms alone react in a formative or deformative way to external stimuli. In warm climates the fur of animals and the wool of sheep become thin and light. The colder the climate, the thicker these coverings. Such facts only show that in the matter of adaptation among living organisms, there is a factor at work other than chemistry and physics—not independent of them, but making a purposive use of them. Cut off the central shoot that leads the young spruce tree upwards, and one of the shoots from the whirl of lateral branches below it slowly rises up and takes the place of the lost leader. Here is an action not prompted by the environment, but by the morphological needs of the tree, and it illustrates how different is its unity from the unity of a mere machine. I am only aiming to point out that in all living things the material forces behave in a purposive way to a degree that cannot be affirmed of them in non-living, and that, therefore, they imply intelligence.

Evidently the cells in the body do not all have the same degree of life,—that is, the same degree of irritability. The bone cells and the hair cells, for instance, can hardly be so much alive—or so irritable—as the muscle cells; nor these as intensely alive as the nerve and brain cells. Does not a bird possess a higher degree of life than a mollusk, or a turtle? Is not a brook trout more alive than a mud-sucker? You can freeze the latter as stiff as an icicle and resuscitate it, but not the former. There is a scale of degrees in life as clearly as there is a scale of degrees in temperature. There is an endless gradation of sensibilities of the living cells, dependent probably upon the degree of differentiation of function. Anaesthetics dull or suspend this irritability. The more highly developed and complex the nervous system, the higher the degree of life, till we pass from mere physical life to psychic life. Science might trace this difference to cell structure, but what brings about the change in the character of the cell, or starts the cells to building a complex nervous system, is a question unanswerable to science. The biologist imagines this and that about the invisible or hypothetical molecular structure; he assigns different functions to the atoms; some are for endosmosis, others for contraction, others for conduction of stimuli. Intramolecular oxygen plays a part. Other names are given to the mystery—the micellar strings of Naegeli, the biophores of Weismann, the plastidules of Haeckel; they all presuppose millions of molecules peculiarly arranged in the protoplasm.

On purely mechanical and chemical principles Tyndall accounts for the growth from the germ of a tree. The germ would be quiet, but the solar light and heat disturb its dreams, break up its atomic equilibrium. The germ makes an "effort" to restore it (why does it make an effort?), which effort is necessarily defeated and incessantly renewed, and in the turmoil or "scrapping" between the germ and the solar forces, matter is gathered from the soil and from the air and built into the special form of a tree. Why not in the form of a cabbage, or a donkey, or a clam? If the forces are purely automatic, why not? Why should matter be gathered in at all in a mechanical struggle between inorganic elements? But these are not all inorganic; the seed is organic. Ah! that makes the difference! That accounts for the "effort." So we have to have the organic to start with, then the rest is easy. No doubt the molecules of the seed would remain in a quiescent state, if they were not disturbed by external influences, chemical and mechanical. But there is something latent or potential in that seed that is the opposite of the mechanical, namely, the vital, and in what that consists, and where it came from, is the mystery.

III

I fancy that the difficulty which an increasing number of persons find in accepting the mechanistic view of life, or evolution,—the view which Herbert Spencer built into such a ponderous system of philosophy, and which such men as Huxley, Tyndall, Gifford, Haeckel, Verworn, and others, have upheld and illustrated,—is temperamental rather than logical. The view is distasteful to a certain type of mind—the flexible, imaginative, artistic, and literary type—the type that loves to see itself reflected in nature or that reads its own thoughts and emotions into nature. In a few eminent examples the two types of mind to which I refer seem more or less blended. Sir Oliver Lodge is a case in point. Sir Oliver is an eminent physicist who in his conception of the totality of things is yet a thoroughgoing idealist and mystic. His solution of the problem of living things is extra-scientific. He sees in life a distinct transcendental principle, not involved in the constitution of matter, but independent of it, entering into it and using it for its own purposes.

Tyndall was another great scientist with an inborn idealistic strain in him. His famous, and to many minds disquieting, declaration, made in his Belfast address over thirty years ago, that in matter itself he saw the promise and the potency of all terrestrial life, stamps him as a scientific materialist. But his conception of matter, as "at bottom essentially mystical and transcendental," stamps him as also an idealist. The idealist in him speaks very eloquently in the passage which, in the same address, he puts into the mouth of Bishop Butler, in the latter's imaginary debate with Lucretius: "Your atoms," says the Bishop, "are individually without sensation, much more are they without intelligence. May I ask you, then, to try your hand upon this problem. Take your dead hydrogen atoms, your dead oxygen atoms, your dead carbon atoms, your dead nitrogen atoms, your dead phosphorus atoms, and all the other atoms, dead as grains of shot, of which the brain is formed. Imagine them separate and sensationless, observe them running together and forming all imaginable combinations. This, as a purely mechanical process, is seeable by the mind. But can you see or dream, or in any way imagine, how out of that mechanical art, and from these individually dead atoms, sensation, thought, and emotion are to arise? Are you likely to extract Homer out of the rattling of dice, or the Differential Calculus out of the clash of billiard balls?" Could any vitalist, or Bergsonian idealist have stated his case better?

Now the Bishop Butler type of mind—the visualizing, idealizing, analogy-loving, literary, and philosophical mind—is shared by a good many people; it is shared by or is characteristic of all the great poets, artists, seers, idealists of the world; it is the humanistic type that sees man everywhere reflected in nature; and is radically different from the strictly scientific type which dehumanizes nature and reduces it to impersonal laws and forces, which distrusts analogy and sentiment and poetry, and clings to a rigid logical method.

This type of mind is bound to have trouble in accepting the physico-chemical theory of the nature and origin of life. It visualizes life, sees it as a distinct force or principle working in and through matter but not of it, super-physical in its origin and psychological in its nature. This is the view Henri Bergson exploits in his "Creative Evolution." This is the view Kant took when he said, "It is quite certain that we cannot even satisfactorily understand, much less explain, the nature of an organism and its internal forces on purely mechanical principles." It is the view Goethe took when he said, "Matter can never exist without spirit, nor spirit without matter."

Tyndall says Goethe was helped by his poetic training in the field of natural history, but hindered as regards the physical and mechanical sciences. "He could not formulate distinct mechanical conceptions; he could not see the force of mechanical reasoning." His literary culture helped him to a literary interpretation of living nature, but not to a scientific explanation of it; it helped put him in sympathy with living things, and just to that extent barred him from the mechanistic conception of those of pure science. Goethe, like every great poet, saw the universe through the colored medium of his imagination, his emotional and aesthetic nature; in short, through his humanism, and not in the white light of the scientific reason. His contributions to literature were of the first order, but his contributions to science have not taken high rank. He was a "prophet of the soul," and not a disciple of the scientific understanding.

If we look upon life as inherent or potential in the constitution of matter, dependent upon outward physical and chemical conditions for its development, we are accounting for life in terms of matter and motion, and are in the ranks of the materialists. But if we find ourselves unable to set the ultimate particles of matter in action, or so working as to produce the reaction which results in life, without conceiving of some new force or principle operating upon them, then we are in the ranks of the vitalists or idealists. The idealists see the original atoms slumbering there in rock and sea and soil for untold ages, till, moved upon by some unknown factor, they draw together in certain fixed order and numbers, and life is the result. Something seems to put a spell upon them and cause them to behave so differently from the way they behaved before they were drawn into the life circuit.

When we think of life, as the materialists do, as of mechanico-chemical origin, or explicable in terms of the natural universal order, we think of the play of material forces amid which we live, we think of their subtle action and interaction all about us—of osmosis, capillarity, radio-activity, electricity, thermism, and the like; we think of the four states of matter,—solid, fluid, gaseous, and ethereal,—of how little our senses take in of their total activities, and we do not feel the need of invoking a transcendental principle to account for it.

Yet to fail to see that what we must call intelligence pervades and is active in all organic nature is to be spiritually blind. But to see it as something foreign to, or separable from, nature is to do violence to our faith in the constancy and sufficiency of the natural order. One star differeth from another star in glory. There are degrees of mystery in the universe. The most mysterious thing in inorganic nature is electricity—that disembodied energy that slumbers in the ultimate particles of matter—unseen, unfelt, unknown, till it suddenly leaps forth with such terrible vividness and power on the face of the storm, or till we summon it through the transformation of some other form of energy. A still higher and more inscrutable mystery is life—that something which clothes itself in such infinitely varied and beautiful as well as unbeautiful forms of matter. We can evoke electricity at will from many different sources, but we can evoke life only from other life; the biogenetic law is inviolable.

IV

It takes some of the cold iron out of the mechanistic theory of life if we divest it of all our associations with the machine-mad and machine-ridden world in which we live and out of which our material civilization came. The mechanical, the automatic, is the antithesis of the spontaneous and the poetic, and it repels us on that account. We are so made that the artificial systems please us far less than the natural systems. A sailing-ship takes us more than a steamship. It is nearer life, nearer the winged creatures. There is determinism in nature, mechanical forces are everywhere operative, but there are no machines in the proper sense of the word. When we call an organism a living machine we at once take it out of the categories of the merely mechanical and automatic and lift it into a higher order—the vital order.

Professor Le Dantec says we are mechanisms in the third degree, a mechanism of a mechanism of a mechanism. The body is a mechanism by virtue of its anatomy—its framework, its levers, its hinges; it is a mechanism by virtue of its chemical activities; and it is a mechanism by virtue of its colloid states—three kinds of mechanisms in one, and all acting together harmoniously and as a unit—in other words, a super-mechanical combination of activities.

The mechanical conception of life repels us because of its association in our minds with the fabrications of our own hands—the dead metal and wood and the noise and dust of our machine-ridden and machine-produced civilization.

But Nature makes no machines like our own. She uses mechanical principles everywhere, in inert matter and in living bodies, but she does not use them in the bald and literal way we do. We must divest her mechanisms of the rigidity and angularity that pertain to the works of our own hands. Her hooks and hinges and springs and sails and coils and aeroplanes, all involve mechanical contrivances, but how differently they impress us from our own application of the same principles! Even in inert matter—in the dews, the rains, the winds, the tides, the snows, the streams,—her mechanics and her chemistry and her hydrostatics and pneumatics, seem much nearer akin to life than our own. We must remember that Nature's machines are not human machines. When we place our machine so that it is driven by the great universal currents,—the wheel in the stream, the sail on the water,—the result is much more pleasing and poetic than when propelled by artificial power. The more machinery we get between ourselves and Nature, the farther off Nature seems. The marvels of crystallization, the beautiful vegetable forms which the frost etches upon the stone flagging of the sidewalk, and upon the window-pane, delight us and we do not reason why. A natural bridge pleases more than one which is the work of an engineer, yet the natural bridge can only stand when it is based upon good engineering principles. I found at the great Colorado Canon, that the more the monuments of erosion were suggestive of human structures, or engineering and architectural works, the more I was impressed by them. We are pleased when Nature imitates man, and we are pleased when man imitates Nature, and yet we recoil from the thought that life is only applied mechanics and chemistry. But the thought that it is mechanics and chemistry applied by something of which they as such, form no part, some agent or principle which we call vitality, is welcome to us. No machine we have ever made or seen can wind itself up, or has life, no chemical compound from the laboratories ever develops a bit of organic matter, and therefore we are disbelievers in the powers of these things.

V

Is gravity or chemical affinity any more real to the mind than vitality? Both are names for mysteries. Something which we call life lifts matter up, in opposition to gravity, into thousands of living forms. The tree lifts potash, silica, and lime up one or two hundred feet into the air; it elbows the soil away from its hole where it enters the ground; its roots split rocks. A giant sequoia lifts tons of solid matter and water up hundreds of feet. So will an explosion of powder or dynamite, but the tree does it slowly and silently by the organizing power of life. The vital is as inscrutably identified with the mechanical and chemical as the soul is identified with the body. They are one while yet they are two.

For purely mechanical things we can find equivalents. Arrest a purely mechanical process, and the machine only rests or rusts; arrest a vital process, and the machine evaporates, disintegrates, myriads of other machines reduce it to its original mineral and gaseous elements. In the organic world we strike a principle that is incalculable in its operation and incommensurable in its results. The physico-chemical forces we can bring to book; we know their orbits, their attractions and repulsions, and just what they will and will not do; we can forecast their movements and foresee their effects. But the vital forces transcend all our mathematics; we cannot anticipate their behavior. Start inert matter in motion and we know pretty nearly what will happen to it; mix the chemical elements together and we can foresee the results; but start processes or reactions we call life, and who can foresee the end? We know the sap will mount in the tree and the tree will be true to its type, but what do we or can we know of what it is that determines its kind and size? We know that in certain plants the leaves will always be opposite each other on the stalk, and that in other plants the leaves will alternate; that certain plants will have conspicuous and others inconspicuous flowers; but how can we know what it is in the cells of the plants that determines these things? We can graft the scion of a sour apple tree upon a sweet, and vice versa, and the fruit of the scion will be true to its kind, but no analysis of the scion or of the stock will reveal the secret, as it would in the case of chemical compounds. In inorganic nature we meet with concretions, but not secretions; with crystallization, but not with assimilation and growth from within. Chemistry tells us that the composition of animal bodies is identical with that of vegetable; that there is nothing in one that is not in the other; and yet, behold the difference! a difference beyond the reach of chemistry to explain. Biology can tell us all about these differences and many other things, but it cannot tell us the secret we are looking for,—what it is that fashions from the same elements two bodies so unlike as a tree and a man.

Decay and disintegration in the inorganic world often lead to the production of beautiful forms. In life the reverse is true; the vital forces build up varied and picturesque forms which when pulled down are shapeless and displeasing. The immense layers of sandstone and limestone out of which the wonderful forms that fill the Grand Canon of the Colorado are carved were laid down in wide uniform sheets; if the waters had deposited their material in the forms which we now see, it would have been a miracle. We marvel and admire as we gaze upon them now; we do more, we have to speculate as to how it was all done by the blind, unintelligent forces. Giant stairways, enormous alcoves, dizzy, highly wrought balustrades, massive vertical walls standing four-square like huge foundations—how did all the unguided erosive forces do it? The secret is in the structure of the rock, in the lines of cleavage, in the unequal hardness, and in the impulsive, irregular, and unequal action of the eroding agents. These agents follow the lines of least resistance; they are active at different times and seasons, and from different directions; they work with infinite slowness; they undermine, they disintegrate, they dislodge, they transport; the hard streaks resist them, the soft streaks invite them; water charged with sand and gravel saws down; the wind, armed with fine sand, rounds off and hollows out; and thus the sculpturing goes on. But after you have reasoned out all these things, you still marvel at the symmetry and the structural beauty of the forms. They look like the handiwork of barbarian gods. They are the handiwork of physical forces which we can see and measure and in a degree control. But what a gulf separates them from the handiwork of the organic forces!

VI

Some things come and some things arise; things that already exist may come, but potential things arise; my friend comes to visit me, the tide comes up the river, the cold or hot wave comes from the west; but the seasons, night and morning, health and disease, and the like, do not come in this sense; they arise. Life does not come to dead matter in this sense; it arises. Day and night are not traveling round the earth, though we view them that way; they arise from the turning of the earth upon its axis. If we could keep up with the flying moments,—that is, with the revolution of the earth,—we could live always at sunrise, or sunset, or at noon, or at any other moment we cared to elect. Love or hate does not come to our hearts; it is born there; the breath does not come to the newborn infant; respiration arises there automatically. See how the life of the infant is involved in that first breath, yet it is not its life; the infant must first be alive before it can breathe. If it is still-born, the respiratory reaction does not take place. We can say, then, that the breath means life, and the life means breath; only we must say the latter first. We can say in the same way that organization means life, and life means organization. Something sets up the organizing process in matter. We may take all the physical elements of life known to us and jumble them together and shake them up to all eternity, and life will not result. A little friction between solid bodies begets heat, a little more and we get fire. But no amount of friction begets life. Heat and life go together, but heat is the secondary factor.

Life is always a vanishing-point, a constant becoming—an unstable something that escapes us while we seem to analyze it. In its nature or essence, it is a metaphysical problem, and not one of physical science. Science cannot grasp it; it evaporates in its crucibles. And science is compelled finally to drive it into an imaginary region—I had almost said, metaphysical region, the region of the invisible, hypothetical atoms of matter. Here in the mysteries of molecular attraction and repulsion, it conceives the secret of life to lie.

"Life is a wave," says Tyndall, but does not one conceive of something, some force or impulse in the wave that is not of the wave? What is it that travels along lifting new water each moment up into waves? It is a physical force communicated usually by the winds. When the wave dies upon the shore, this force is dissipated, not lost, or is turned into heat. Why may we not think of life as a vital force traveling through matter and lifting up into organic life waves in the same way? But not translatable into any other form of energy because not derivable from any other form.

Every species of animal has something about it that is unique and individual and that no chemical or physiological analysis of it will show—probably some mode of motion among its ultimate particles that is peculiar to itself. This prevents cross-breeding among different species and avoids a chaos of animal and vegetable forms. Living tissues and living organs from one species cannot be grafted upon the individuals of another species; the kidney of a cat, for instance, cannot be substituted for that of a dog, although the functions and the anatomy of the two are identical. It is suggested that an element of felineness and an element of canineness adhere in the cells of each, and the two are antagonistic. This specific quality, or selfness, of an animal pervades every drop of its blood, so that the blood relationship of the different forms may be thus tested, where chemistry is incompetent to show agreement or antagonism. The reactions of life are surer and more subtle than those of chemistry. Thus the blood relationship between birds and reptiles is clearly shown, as is the relationship of man and the chimpanzee and the orang-outang. The same general fact holds true in the vegetable world. You cannot graft the apple upon the oak, or the plum upon the elm. It seems as if there were the quality of oakness and the quality of appleness, and they would not mix.

The same thing holds among different chemical compounds. Substances which have precisely the same chemical formulae (called isomers) have properties as widely apart as alcohol and ether.

If chemistry is powerless to trace the relationship between different forms of life, is it not highly improbable that the secret of life itself is in the keeping of chemistry?

Analytical science has reached the end of its tether when it has resolved a body into its constituent elements. Why or how these elements build up a man in the one case, and a monkey in another, is beyond its province to say. It can deal with all the elements of the living body, vegetable and animal; it can take them apart and isolate them in different bottles; but it cannot put them together again as they were in life. It knows that the human body is built up of a vast multitude of minute cells, that these cells build tissues, that the tissues build organs, that the organs build the body; but the secret of the man, or the dog, or even the flea, is beyond its reach. The secret of biology, that which makes its laws and processes differ so widely from those of geology or astronomy, is a profound mystery. Science can take living tissue and make it grow outside of the body from which it came, but it will only repeat endlessly the first step of life—that of cell-multiplication; it is like a fire that will burn as long as fuel is given it and the ashes are removed; but it is entirely purposeless; it will not build up the organ of which it once formed a part, much less the whole organized body.

The difference between one man and another does not reside in his anatomy or physiology, or in the elements of which the brains and bodies are composed, but in something entirely beyond the reach of experimental science to disclose. The difference is psychological, or, we may say, philosophical, and science is none the wiser for it. The mechanics and the chemistry of a machine are quite sufficient to account for it, plus the man behind it. To the physics and chemistry of a living body, we are compelled to add some intangible, unknowable principle or tendency that physics and chemistry cannot disclose or define. One hesitates to make such a statement lest he do violence to that oneness, that sameness, that pervades the universe.

All trees go to the same soil for their ponderable elements, their ashes, and to the air and the light for their imponderable,—their carbon and their energy,—but what makes the tree, and makes one tree differ from another? Has the career of life upon this globe, the unfolding of the evolutionary process, been accounted for when you have named all the physical and material elements and processes which it involves? We take refuge in the phrase "the nature of things," but the nature of things evidently embraces something not dreamed of in our science.

VII

It is reported that a French scientist has discovered the secret of the glow-worm's light. Of course it is a chemical reaction,—what else could it be?—but it is a chemical reaction in a vital process. Our mental and spiritual life—our emotions of art, poetry, religion—are inseparable from physical processes in the brain and the nervous system; but is that their final explanation? The sunlight has little effect on a withered leaf, but see what effect it has upon the green leaf upon the tree! The sunlight is the same, but it falls upon a new force or potency in the chlorophyll of the leaf,—a bit of chemistry there inspired by life,—and the heat of the sun is stored up in the carbon or woody tissues of the plant or tree, to be given out again in our stoves or fireplaces. And behold how much more of the solar heat is stored up in one kind of a tree than in certain other kinds,—how much in the hickory, oak, maple, and how little comparatively in the pine, spruce, linden,—all through the magic of something in the leaf, or shall we say of the spirit of the tree? If the laws of matter and force alone account for the living organism, if we do not have to think of something that organizes, then how do we account for the marvelous diversity of living forms, and their still more marvelous power of adaptation to changed conditions, since the laws of matter and force are the same everywhere? Science can deal only with the mechanism and chemistry of life, not with its essence; that which sets up the new activity in matter that we call vital is beyond its analysis. It is hard to believe that we have told the whole truth about a living body when we have enumerated all its chemical and mechanical activities. It is by such enumeration that we describe a watch, or a steam-engine, or any other piece of machinery. Describe I say, but such description does not account for the watch or tell us its full significance. To do this, we must include the watchmaker, and the world of mind and ideas amid which he lives. Now, in a living machine, the machine and the maker are one. The watch is perpetually self-wound and self-regulated and self-repaired. It is made up of millions of other little watches, the cells, all working together for one common end and ticking out the seconds and minutes of life with unfailing regularity. Unlike the watch we carry in our pockets, if we take it apart so as to stop its ticking, it can never be put together again. It has not merely stopped; it is dead.

The late William Keith Brooks, of Johns Hopkins University, said in opposition to Huxley that he held to the "old-fashioned conviction that living things do in some way, and in some degree, control or condition inorganic nature; that they hold their own by setting the mechanical properties of matter in opposition to each other, and that this is their most notable and distinctive characteristic." And yet, he said, to think of the living world as "anything but natural" is impossible.

VIII

Life seems to beget a new kind of chemistry, the same elements behave so differently when they are drawn into the life circuit from what they did before. Carbon, for instance, enters into hundreds of new compounds in the organic world that are unknown in the inorganic world. I am thus speaking of life as if it were something, some force or agent, that antedates its material manifestations, whereas in the eyes of science there is no separation of the one from the other. In an explosion there is usually something anterior to, or apart from, the explosive compound, that pulls the trigger, or touches the match, or completes the circuit, but in the slow and gentle explosions that keep the life machinery going, we cannot make such a distinction. The spark and the powder are one; the gun primes and fires itself; the battery is perpetually self-charged; the lamp is self-trimmed and self-lit.

Sir Oliver Lodge is apparently so impressed with some such considerations that he spiritualizes life, and makes it some mysterious entity in itself, existing apart from the matter which it animates and uses; not a source of energy but a timer and releaser of energy. Henri Bergson, in his "Creative Evolution," expounds a similar philosophy of life. Life is a current in opposition to matter which it enters into, and organizes into the myriads of living forms.

I confess that it is easier for me to think of life in these terms than in terms of physical science. The view falls in better with our anthropomorphic tendencies. It appeals to the imagination and to our myth-making aptitudes. It gives a dramatic interest to the question. With Bergson we see life struggling with matter, seeking to overcome its obduracy, compromising with it, taking a half-loaf when it cannot get a whole one; we see evolution as the unfolding of a vast drama acted upon the stage of geologic time. Creation becomes a perpetual process, the creative energy an ever-present and familiar fact. Bergson's book is a wonderful addition to the literature of science and of philosophy. The poet, the dreamer, the mystic, in each of us takes heart at Bergson's beautiful philosophy; it seems like a part of life; it goes so well with living things. As James said, it is like the light of the morning and the singing of birds; we glory in seeing the intellect humbled as he humbles it. The concepts of science try our mettle. They do not appeal to our humanity, or to our myth-making tendencies; they appeal to the purely intellectual, impersonal force within us. Though all our gods totter and fall, science goes its way; though our hearts are chilled and our lives are orphaned, science cannot turn aside, or veil its light. It does not temper the wind to the shorn lamb.

Hence the scientific conception of the universe repels many people. They are not equal to it. To think of life as involved in the very constitution of matter itself is a much harder proposition than to conceive of it as Bergson and Sir Oliver Lodge do, as an independent reality. The latter view gives the mind something more tangible to lay hold of. Indeed, science gives the mind nothing to take hold of. Does any chemical process give the mind any separate reality to take hold of? Is there a spirit of fire, or of decay, or of disease, or of health?

IX

Behold a man with his wonderful body, and still more wonderful mind; try to think of him as being fathered and mothered by the mere mechanical and chemical forces that we see at work in the rocks and soil underfoot, begotten by chemical affinity or the solar energy working as molecular physic, and mothered by the warmth and moisture, by osmosis and the colloid state—and all through the chance clashings and groupings of the irrational physical forces. Nothing is added to them, nothing guides or inspires them, nothing moves upon the face of the waters, nothing breathes upon the insensate clay. The molecules or corpuscles of the four principal elements—carbon, hydrogen, nitrogen, and oxygen—just happened to come together in certain definite numbers, and in a certain definite order, and invented or built up that most marvelous thing in the universe, the cell. The cells put their heads, or bodies, together, and built the tissues, the tissues formed the organs, the organs in convention assembled organized themselves into the body, and behold! a man, a bird, or a tree!—as chance a happening as the juxtaposition of the grains of sand upon the shore, or the shape of the summer clouds in the sky.

Aristotle dwells upon the internal necessity. The teeth of an animal arise from necessity, he says; the animal must have them in order to live. Yet it must have lived before it had them, else how would the necessity arise? If the horns of an animal arise from the same necessity, the changing conditions of its life begat the necessity; its life problem became more and more complicated, till new tools arose to meet new wants. But without some indwelling principle of development and progress, how could the new wants arise? Spencer says this progress is the result of the action and reaction between organisms and their changing environment. But you must first get your organism before the environment can work its effects, and you must have something in the organism that organizes and reacts from the environment. We see the agents he names astronomic, geologic, meteorologic, having their effects upon inanimate objects as well, but they do not start the process of development in them; they change a stone, but do not transform it into an organism. The chemist can take the living body apart as surely as the watchmaker can take a watch apart, but he cannot put the parts together again so that life will reappear, as the watchmaker can restore the time-keeping power of the watch. The watch is a mere mechanical contrivance with parts fitted to parts externally, while the living body is a mechanical and chemical contrivance, with parts blended with parts internally, so to speak, and acting together through sympathy, and not merely by mechanical adjustment. Do we not have to think of some organizing agent embracing and controlling all the parts, and integral in each of them, making a vital bond instead of a mechanical one?

There are degrees of vitality in living things, whereas there are only degrees of complexity and delicacy and efficiency in mechanical contrivances. One watch differs from another in the perfection of its works, but not as two living bodies with precisely similar structure differ from each other in their hold upon life, or in their measure of vitality. No analysis possible to science could show any difference in the chemistry and physics of two persons of whom one would withstand hardships and diseases that would kill the other, or with whom one would have the gift of long life and the other not. Machines differ from one another quantitatively—more or less efficiency; a living body differs from a machine qualitatively—its efficiency is of a different order; its unity is of a different order; its complexity is of a different order; the interdependence of its parts is of a different order. Yet what a parallel there is between a machine and a living body! Both are run by external forces or agents, solar energy in one applied mechanically from without; in the other applied vitally from within; both suffer from the wear and tear of time and from abuse, but one is self-repaired and the other powerless in this respect—two machines with the same treatment running the same number of years, but two men with the same treatment running a very unequal number of years. Machines of the same kind differ in durability, men differ in powers of endurance; a man can "screw up his courage," but a machine has no courage to screw up. Science may be unable to see any difference between vital mechanics, vital chemistry, and the chemics and mechanics of inorganic bodies—its analysis reveals no difference; but that there is a difference as between two different orders, all men see and feel.

Science cannot deal with fundamental questions. Only philosophy can do this. Science is only a tool or a key, and it can unlock only certain material problems. It cannot appraise itself. It is not a judge but a witness. Problems of mind, of character, moral, aesthetic, literary, artistic problems, are not its sphere. It counts and weighs and measures and analyzes, it traces relations, but it cannot appraise its own results. Science and religion come in conflict only when the latter seeks to deal with objective facts, and the former seeks to deal with subjective ideas and emotions. On the question of miracle they clash, because religion is then dealing with natural phenomena and challenges science. Philosophy offends science when it puts its own interpretation upon scientific facts. Science displeases literature when it dehumanizes nature and shows us irrefragable laws when we had looked for humanistic divinities.



XI

THE ARRIVAL OF THE FIT

In my youth I once heard the then well-known lecturer Starr King speak on "The Law of Disorder." I have no recollection of the main thought of his discourse, but can see that it might have been upon the order and harmony that finally come out of the disharmonies of nature and of man. The whole universe goes blundering on, but surely arrives. Collisions and dispersions in the heavens above, and failure and destruction among living things on the earth below, yet here we all are in a world good to be in! The proof that it is good to be in is that we are actually here. It is as if the Creator played his right hand against his left—what one loses the other gains.

It has been aptly said that while Darwin's theory of natural selection may account for the survival of the fittest, it does not account for the arrival of the fittest. The arrival of the fittest, sooner or later, seems in some way guaranteed by tendencies that are beyond the hit-and-miss method of natural selection.

When we look back over the course of organic evolution, we see the unfolding of a great drama, or tragedy, in which, for millions upon millions of years the sole actors are low and all but brainless forms of life, devouring and devoured, in the old seas. We see, during other millions upon millions of years, a savage carnival of huge bestial forms upon the land, amphibian monsters and dragons of the land and air, devouring and being devoured, a riot of blood and carnage. We see the shifting of land and sea, the folding and crumpling of the earth's crust, the rise of mountains, the engulfing of forests, a vast destruction of life, immense numbers of animal forms becoming extinct through inability to adapt themselves to new conditions, or from other causes. We see creatures, half beast, half bird, or half dragon, half fish; we see the evolutionary process thwarted or delayed apparently by the hardening or fixing of its own forms. We see it groping its way like a blind man, and experimenting with this device and with that, fumbling, awkward, ineffectual, trying magnitude of body and physical strength first, and then shifting the emphasis to size of brain and delicacy and complexity of nerve-organization, pushing on but gropingly, learning only by experience, regardless of pain and waste and suffering; whole races of sentient beings swept away by some terrestrial cataclysm, as at the end of Palaeozoic and Mesozoic times; prodigal, inhuman, riotous, arming some vegetable growths with spurs and thorns that tear and stab, some insects with stings, some serpents with deadly fangs, the production of pain as much a part of the scheme of things as the production of pleasure; the creative impulse feeling its way through the mollusk to the fish, and through the fish to the amphibian and the reptile, through the reptile to the mammal, and through the mammal to the anthropoid apes, and through the apes to man, then through the rude and savage races of man, the long-jawed, small-brained, Pliocene man, hairy and savage, to the cave-dwellers and stone-implement man of Pleistocene times, and so on to our rude ancestors whom we see dimly at the dawn of history, and thus rapidly upward to the European man of our own era. What a record! What savagery, what thwartings and delays, what carnage and suffering, what an absence of all that we mean by intelligent planning and oversight, of love, of fatherhood! Just a clash of forces, the battle to the strong and the race to the fleet.

It is hard to believe that the course of organic evolution would have eventuated in man and the other higher forms of life without some guiding principle; yet it is equally difficult to believe that the course of any guiding intelligence down the ages would have been strewn with so many failures and monstrosities, so much waste and suffering and delay. Man has not been specially favored by one force or element in nature. Behold the enemies that beset him without and within, and that are armed for his destruction! The intelligence that appears to pervade the organic world, and that reaches its conscious expression in the brain of man, is just as manifest in all the forms of animals and plants that are inimical to him, in all his natural enemies,—venomous snakes and beasts of prey, and insect pests,—as in anything else. Nature is as wise and solicitous for rats and mice as for men. In fact, she has endowed many of the lower creatures with physical powers that she has denied him. Evidently man is only one of the cards in her pack; doubtless the highest one, but the game is not played for him alone.

There is no economy of effort or of material in nature as a whole, whatever there may be in special parts. The universe is not run on modern business-efficiency principles. There is no question of time, or of profit, of solvency or insolvency. The profit-and-loss account in the long run always balances. In our astronomic age there are probably vastly more dead suns and planets strewing the depths of sidereal space than there are living suns and planets. But in some earlier period in the cycle of time the reverse may have been true, or it may be true in some future period.

There is economy of effort in the individual organism, but not in the organic series, at least from the human point of view. During the biologic ages there have been a vast number of animal forms, great and small, and are still, that had no relation to man, that were not in his line of descent, and played no part in his evolution. During that carnival of monstrous and gigantic forms in Mesozoic time the ancestor of man was probably some small and insignificant creature whose life was constantly imperiled by the huge beasts about it. That it survived at all in the clash of forces, bestial and elemental, during those early ages, is one of the wonders of time. The drama or tragedy of evolution has had many actors, some of them fearful and terrible to look upon, who have played their parts and passed off the stage, as if the sole purpose was the entertainment of some unseen spectator. When we reach human history, what wasted effort, what failures, what blind groping, what futile undertakings!—war, famine, pestilence, delaying progress or bringing to naught the wisdom of generations of men! Those who live in this age are witnessing in the terrible European war something analogous to the blind, wasteful fury of the elemental forces; millions of men who never saw one another, and who have not the shadow of a quarrel, engage in a life-and-death struggle, armed with all the aids that centuries of science and civilization can give them—a tragedy that darkens the very heavens and makes a mockery of all our age-old gospel of peace and good will to men. It is a catastrophe on a scale with the cataclysms of geologic time when whole races disappeared and the face of continents was changed. It seems that men in the aggregate, with all their science and religion, are no more exempt from the operation of cosmic laws than are the stocks and stones. Each party to this gigantic struggle declares that he is in it against his will; the fate that rules in the solar system seems to have them all in its grip; the working of forces and tendencies for which no man was responsible seems to have brought it about. Social communities grow in grace and good-fellowship, but governments in their relations to one another, and often in relation to their own subjects, are still barbarous. Men become christianized, but man is still a heathen, the victim of savage instincts. In this struggle one of the most admirable and efficient of nations, and one of the most solicitous for the lives and well-being of its citizens, is suddenly seized with a fury of destruction, hurling its soldiers to death as if they were only the waste of the fields, and trampling down other peoples whose geographic position placed them in their way as if they were merely vermin, throwing international morality to the winds, looking upon treaties as "scraps of paper," regarding themselves as the salt of the earth, the chosen of the Lord, appropriating the Supreme Being as did the colossal egotism of old Israel, and quickly getting down to the basic principle of savage life—that might makes right.

Little wonder that the good people are asking, Have we lost faith? We may or we may not have lost faith, but can we not see that our faith does not give us a key to the problem? Our faith is founded on the old prescientific conception of a universe in which good and evil are struggling with each other, with a Supreme Being aiding and abetting the good. We fail to appreciate that the cosmic laws are no respecters of persons. Emerson says there is no god dare wrong a worm, but worms dare wrong one another, and there is no god dare take sides with either. The tides in the affairs of men are as little subject to human control as the tides of the sea and the air. We may fix the blame of the European war upon this government or upon that, but race antagonisms and geographical position are not matters of choice. An island empire, like England, is bound to be jealous of all rivals upon the sea, because her very life, when nations clash, depends upon her control of it; and an inland empire, like Germany, is bound to grow restless under the pressure of contiguous states of other races. A vast empire, like Russia, is always in danger of falling apart by its own weight. It is fused and consolidated by a turn of events that arouse the patriotic emotions of the whole people and unite them in a common enthusiasm.

The evolution of nations is attended by the same contingencies, the same law of probability, the same law of the survival of the fit, as are organic bodies. I say the survival of the fit; there are degrees of fitness in the scale of life; the fit survive, and the fittest lead and dominate, as did the reptiles in Mesozoic time, and the mammals in Tertiary time. Among the mammals man is dominant because he is the fittest. Nations break up or become extinct when they are no longer fit, or equal to the exigencies of the struggles of life. The Roman Empire would still exist if it had been entirely fit. The causes of its unfitness form a long and intricate problem. Germany of to-day evidently looks upon herself as the dominant nation, the one fittest to survive, and she has committed herself to the desperate struggle of justifying her self-estimate. She tramples down weaker nations as we do the stubble of the fields. She would plough and harrow the world to plant her Prussian Kultur. This Kultur is a mighty good product, but we outside of its pale think that French Kultur, and English Kultur, and American Kultur are good products also, and equally fit to survive. We naturally object to being ploughed under. That Russian Kultur has so far proved itself a vastly inferior product cannot be doubted, but the evolutionary processes will in time bring a finer and higher Russia out of this vast weltering and fermenting mass of humanity. In all these things impersonal laws and forces are at work, and the balance of power, if temporarily disturbed, is bound, sooner or later, to be restored just as it is in the inorganic realm.

Evolution is creative, as Bergson contends. The wonder is that, notwithstanding the indifference of the elemental forces and the blind clashing of opposing tendencies among living forms,—a universe that seems run entirely on the trial-and-error principle,—evolution has gone steadily forward, a certain order and stability has been reached in the world of inert bodies and forces, and myriads of forms of wonderful fitness and beauty have been reached in the organic realm. Just as the water-system and the weather-system of the globe have worked themselves out on the hit-and-miss plan, but not without serious defects,—much too much water and heat at a few places, and much too little at a few others,—so the organic impulse, warred upon by the blind inorganic elements and preyed upon by the forms it gave rise to, has worked itself out and peopled the world as we see it peopled to-day—not with forms altogether admirable and lovely from our point of view, but so from the point of view of the whole. The forests get themselves planted by the go-as-you-please winds and currents, the pines in one place, the spruce, the oaks, the elms, the beeches, in another, all with a certain fitness and system. The waters gather themselves together in great bodies and breathe salubrity and fertility upon the land.

A certain order and reasonableness emerges from the chaos and cross-purposes. There are harmony and cooeperation among the elemental forces, as well as strife and antagonism. Life gets on, for all groping and blundering. There is the inherent variability of living forms to begin with—the primordial push toward the development from within which, so far as we can see, is not fortuitous, but predestined; and there is the stream of influences from without, constantly playing upon and modifying the organism and taken advantage of by it.

The essence of life is in adaptability; it goes into partnership with the forces and conditions that surround it. It is this trait which leads the teleological philosopher to celebrate the fitness of the environment when its fitness is a foregone conclusion. Shall we praise the fitness of the air for breathing, or of the water for drinking, or of the winds for filling our sails? If we cannot say explicitly, without speaking from our anthropomorphism, that there is a guiding intelligence in the evolution of living forms, we can at least say, I think, that the struggle for life is favored by the very constitution of the universe and that man in some inscrutable way was potential in the fiery nebula itself.



XII

THE NATURALIST'S VIEW OF LIFE

I

William James said that one of the privileges of a philosopher was to contradict other philosophers. I may add in the same spirit that one of the fatalities of many philosophers is, sooner or later, to contradict themselves. I do not know that James ever contradicted himself, but I have little doubt that a critical examination of his works would show that he sometimes did so; I remember that he said he often had trouble to make both ends of his philosophy meet. Any man who seeks to compass any of the fundamental problems with the little span of his finite mind, is bound at times to have trouble to make both ends meet. The man of science seldom has any such trouble with his problems; he usually knows what is the matter and forthwith seeks to remedy it. But the philosopher works with a much more intangible and elusive material, and is lucky if he is ever aware when both ends fail to meet.

I have often wondered if Darwin, who was a great philosopher as well as a great man of science, saw or felt the contradiction between his theory of the origin of species through natural selection working upon fortuitous variations, and his statement, made in his old age, that he could not look upon man, with all his wonderful powers, as the result of mere chance. The result of chance man certainly is—is he not?—as are all other forms of life, if evolution is a mere mechanical process set going and kept going by the hit-and-miss action of the environment upon the organism, or by the struggle for existence. If evolution involves no intelligence in nature, no guiding or animating principle, then is not man an accidental outcome of the blind clashing and jolting of the material forces, as much so as the great stone face in the rocks which Hawthorne used so suggestively in one of his stories?

I have wondered if Huxley was aware that both ends of his argument did not quite meet when he contended for the truth of determinism—that there is and can be no free or spontaneous volition; and at the same time set man apart from the cosmic order, and represented him as working his will upon it, crossing and reversing its processes. In one of his earlier essays, Huxley said that to the student of living things, as contrasted with the student of inert matter, the aspect of nature is reversed. "In living matter, incessant, and so far as we know, spontaneous, change is the rule, rest the exception, the anomaly, to be accounted for. Living things have no inertia, and tend to no equilibrium," except the equilibrium of death. This is good vitalistic doctrine, as far as it goes, yet Huxley saw no difference between the matter of life and other matter, except in the manner in which the atoms are aggregated. Probably the only difference between a diamond and a piece of charcoal, or between a pearl and an oyster-shell, is the manner in which the atoms are aggregated; but that the secret of life is in the peculiar compounding of the atoms or molecules—a spatial arrangement of them—is a harder proposition. It seems to me also that Haeckel involves himself in obvious contradictions when he ascribes will, sensation, inclination, dislike, though of a low order, to the atoms of matter; in fact, sees them as living beings with souls, and then denies soul, will, power of choice, and the like to their collective unity in the brain of man.