THE

BREATH OF LIFE

BY

JOHN BURROUGHS

BOSTON AND NEW YORK
HOUGHTON MIFFLIN COMPANY
The Riverside Press Cambridge

COPYRIGHT, 1915,
BY JOHN BURROUGHS

ALL RIGHTS RESERVED

Published May 1915

PREFACE

As life nears its end with me, I find myself meditating more and more upon the mystery of its nature and origin, yet without the least hope that I can find out the ways of the Eternal in this or in any other world. In these studies I fancy I am about as far from mastering the mystery as the ant which I saw this morning industriously exploring a small section of the garden walk is from getting a clear idea of the geography of the North American Continent. But the ant was occupied and was apparently happy, and she must have learned something about a small fraction of that part of the earth's surface.

I have passed many pleasant summer days in my hay-barn study, or under the apple trees, exploring these questions, and though I have not solved them, I am satisfied with the clearer view I have given myself of the mystery that envelops them. I have set down in these pages all the thoughts that have come to me on this subject. I have not aimed so much at consistency as at clearness and definiteness of statement, letting my mind drift as upon a shoreless sea. Indeed, what are such questions, and all other ultimate questions, but shoreless seas whereon the chief reward of the navigator is the joy of the adventure?

Sir Thomas Browne said, over two hundred years ago, that in philosophy truth seemed double-faced, by which I fancy he meant that there was always more than one point of view of all great problems, often contradictory points of view, from which truth is revealed. In the following pages I am aware that two ideas, or principles, struggle in my mind for mastery. One is the idea of the super-mechanical and the super-chemical character of living things; the other is the idea of the supremacy and universality of what we call natural law. The first probably springs from my inborn idealism and literary habit of mind; the second from my love of nature and my scientific bent. It is hard for me to reduce the life impulse to a level with common material forces that shape and control the world of inert matter, and it is equally hard for me to reconcile my reason to the introduction of a new principle, or to see anything in natural processes that savors of the ab-extra. It is the working of these two different ideas in my mind that seems to give rise to the obvious contradictions that crop out here and there throughout this volume. An explanation of life phenomena that savors of the laboratory and chemism repels me, and an explanation that savors of the theological point of view is equally distasteful to me. I crave and seek a natural explanation of all phenomena upon this earth, but the word "natural" to me implies more than mere chemistry and physics. The birth of a baby, and the blooming of a flower, are natural events, but the laboratory methods forever fail to give us the key to the secret of either.

I am forced to conclude that my passion for nature and for all open-air life, though tinged and stimulated by science, is not a passion for pure science, but for literature and philosophy. My imagination and ingrained humanism are appealed to by the facts and methods of natural history. I find something akin to poetry and religion (using the latter word in its non-mythological sense, as indicating the sum of mystery and reverence we feel in the presence of the great facts of life and death) in the shows of day and night, and in my excursions to fields and woods. The love of nature is a different thing from the love of science, though the two may go together. The Wordsworthian sense in nature, of "something far more deeply interfused" than the principles of exact science, is probably the source of nearly if not quite all that this volume holds. To the rigid man of science this is frank mysticism; but without a sense of the unknown and unknowable, life is flat and barren. Without the emotion of the beautiful, the sublime, the mysterious, there is no art, no religion, no literature. How to get from the clod underfoot to the brain and consciousness of man without invoking something outside of, and superior to, natural laws, is the question. For my own part I content myself with the thought of some unknown and doubtless unknowable tendency or power in the elements themselves—a kind of universal mind pervading living matter and the reason of its living, through which the whole drama of evolution is brought about.

This is getting very near to the old teleological conception, as it is also near to that of Henri Bergson and Sir Oliver Lodge. Our minds easily slide into the groove of supernaturalism and spiritualism because they have long moved therein. We have the words and they mould our thoughts. But science is fast teaching us that the universe is complete in itself; that whatever takes place in matter is by virtue of the force of matter; that it does not defer to or borrow from some other universe; that there is deep beneath deep in it; that gross matter has its interior in the molecule, and the molecule has its interior in the atom, and the atom has its interior in the electron, and that the electron is matter in its fourth or non-material state—the point where it touches the super-material. The transformation of physical energy into vital, and of vital into mental, doubtless takes place in this invisible inner world of atoms and electrons. The electric constitution of matter is a deduction of physics. It seems in some degree to bridge over the chasm between what we call the material and the spiritual. If we are not within hailing distance of life and mind, we seem assuredly on the road thither. The mystery of the transformation of the ethereal, imponderable forces into the vital and the mental seems quite beyond the power of the mind to solve. The explanation of it in the bald terms of chemistry and physics can never satisfy a mind with a trace of idealism in it.

The greater number of the chapters of this volume are variations upon a single theme,—what Tyndall called "the mystery and the miracle of vitality,"—and I can only hope that the variations are of sufficient interest to justify the inevitable repetitions which occur. I am no more inclined than Tyndall was to believe in miracles unless we name everything a miracle, while at the same time I am deeply impressed with the inadequacy of all known material forces to account for the phenomena of living things.

That word of evil repute, materialism, is no longer the black sheep in the flock that it was before the advent of modern transcendental physics. The spiritualized materialism of men like Huxley and Tyndall need not trouble us. It springs from the new conception of matter. It stands on the threshold of idealism or mysticism with the door ajar. After Tyndall had cast out the term "vital force," and reduced all visible phenomena of life to mechanical attraction and repulsion, after he had exhausted physics, and reached its very rim, a mighty mystery still hovered beyond him. He recognized that he had made no step toward its solution, and was forced to confess with the philosophers of all ages that

"We are such stuff

As dreams are made on, and our little life

Is rounded with a sleep."

CONTENTS

The reproduction of the bust of Mr. Burroughs which appears as the frontispiece to this volume is used by courtesy of the sculptor, C. S. Pietro.


I

THE BREATH OF LIFE

I

When for the third or fourth time during the spring or summer I take my hoe and go out and cut off the heads of the lusty burdocks that send out their broad leaves along the edge of my garden or lawn, I often ask myself, "What is this thing that is so hard to scotch here in the grass?" I decapitate it time after time and yet it forthwith gets itself another head. We call it burdock, but what is burdock, and why does it not change into yellow dock, or into a cabbage? What is it that is so constant and so irrepressible, and before the summer is ended will be lying in wait here with its ten thousand little hooks to attach itself to every skirt or bushy tail or furry or woolly coat that comes along, in order to get free transportation to other lawns and gardens, to green fields and pastures new?

It is some living thing; but what is a living thing, and how does it differ from a mechanical and non-living thing? If I smash or overturn the sundial with my hoe, or break the hoe itself, these things stay smashed and broken, but the burdock mends itself, renews itself, and, if I am not on my guard, will surreptitiously mature some of the burs before the season is passed.

Evidently a living thing is radically different from a mechanical thing; yet modern physical science tells me that the burdock is only another kind of machine, and manifests nothing but the activity of the mechanical and chemical principles that we see in operation all about us in dead matter; and that a little different mechanical arrangement of its ultimate atoms would turn it into a yellow dock or into a cabbage, into an oak or into a pine, into an ox or into a man.

I see that it is a machine in this respect, that it is set going by a force exterior to itself—the warmth of the sun acting upon it, and upon the moisture in the soil; but it is unmechanical in that it repairs itself and grows and reproduces itself, and after it has ceased running can never be made to run again. After I have reduced all its activities to mechanical and chemical principles, my mind seems to see something that chemistry and mechanics do not explain—something that avails itself of these forces, but is not of them. This may be only my anthropomorphic way of looking at things, but are not all our ways of looking at things anthropomorphic? How can they be any other? They cannot be deific since we are not gods. They may be scientific. But what is science but a kind of anthropomorphism? Kant wisely said, "It sounds at first singular, but is none the less certain, that the understanding does not derive its laws from nature, but prescribes them to nature." This is the anthropomorphism of science.

If I attribute the phenomenon of life to a vital force or principle, am I any more unscientific than I am when I give a local habitation and a name to any other causal force, as gravity, chemical affinity, cohesion, osmosis, electricity, and so forth? These terms stand for certain special activities in nature and are as much the inventions of our own minds as are any of the rest of our ideas.

We can help ourselves out, as Haeckel does, by calling the physical forces—such as the magnet that attracts the iron filings, the powder that explodes, the steam that drives the locomotive, and the like—"living inorganics," and looking upon them as acting by "living force as much as the sensitive mimosa does when it contracts its leaves at touch." But living force is what we are trying to differentiate from mechanical force, and what do we gain by confounding the two? We can only look upon a living body as a machine by forming new conceptions of a machine—a machine utterly unmechanical, which is a contradiction of terms.

A man may expend the same kind of force in thinking that he expends in chopping his wood, but that fact does not put the two kinds of activity on the same level. There is no question but that the food consumed is the source of the energy in both cases, but in the one the energy is muscular, and in the other it is nervous. When we speak of mental or spiritual force, we have as distinct a conception as when we speak of physical force. It requires physical force to produce the effect that we call mental force, though how the one can result in the other is past understanding. The law of the correlation and conservation of energy requires that what goes into the body as physical force must come out in some form of physical force—heat, light, electricity, and so forth.

Science cannot trace force into the mental realm and connect it with our states of consciousness. It loses track of it so completely that men like Tyndall and Huxley and Spencer pause before it as an inscrutable mystery, while John Fiske helps himself out with the conception of the soul as quite independent of the body, standing related to it as the musician is related to his instrument. This idea is the key to Fiske's proof of the immortality of the soul. Finding himself face to face with an insoluble mystery, he cuts the knot, or rather, clears the chasm, by this extra-scientific leap. Since the soul, as we know it, is inseparably bound up with physical conditions, it seems to me that a more rational explanation of the phenomenon of mentality is the conception that the physical force and substance that we use up in a mental effort or emotional experience gives rise, through some unknown kind of molecular activity, to something which is analogous to the electric current in a live wire, and which traverses the nerves and results in our changing states of consciousness. This is the mechanistic explanation of mind, consciousness, etc., but it is the only one, or kind of one, that lends itself to scientific interpretation. Life, spirit, consciousness, may be a mode of motion as distinct from all other modes of motion, such as heat, light, electricity, as these are distinct from each other.

When we speak of force of mind, force of character, we of course speak in parables, since the force here alluded to is an experience of our own minds entirely and would not suffice to move the finest dust-particle in the air.

There could be no vegetable or animal life without the sunbeam, yet when we have explained or accounted for the growth of a tree in terms of the chemistry and physics of the sunbeam, do we not have to figure to ourselves something in the tree that avails itself of this chemistry, that uses it and profits by it? After this mysterious something has ceased to operate, or play its part, the chemistry of the sunbeam is no longer effective, and the tree is dead.

Without the vibrations that we call light, there would have been no eye. But, as Bergson happily says, it is not light passively received that makes the eye; it is light meeting an indwelling need in the organism, which amounts to an active creative principle, that begets the eye. With fish in underground waters this need does not arise; hence they have no sight. Fins and wings and legs are developed to meet some end of the organism, but if the organism were not charged with an expansive or developing force or impulse, would those needs arise?

Why should the vertebrate series have risen through the fish, the reptile, the mammal, to man, unless the manward impulse was inherent in the first vertebrate; something that struggled, that pushed on and up from the more simple to the more complex forms? Why did not unicellular life always remain unicellular? Could not the environment have acted upon it endlessly without causing it to change toward higher and more complex forms, had there not been some indwelling aboriginal tendency toward these forms? How could natural selection, or any other process of selection, work upon species to modify them, if there were not something in species pushing out and on, seeking new ways, new forms, in fact some active principle that is modifiable?

Life has risen by stepping-stones of its dead self to higher things. Why has it risen? Why did it not keep on the same level, and go through the cycle of change, as the inorganic does, without attaining to higher forms? Because, it may be replied, it was life, and not mere matter and motion—something that lifts matter and motion to a new plane.

Under the influence of the life impulse, the old routine of matter—from compound to compound, from solid to fluid, from fluid to gaseous, from rock to soil, the cycle always ending where it began—is broken into, and cycles of a new order are instituted. From the stable equilibrium which dead matter is always seeking, the same matter in the vital circuit is always seeking the state of unstable equilibrium, or rather is forever passing between the two, and evolving the myriad forms of life in the passage. It is hard to think of the process as the work of the physical and chemical forces of inorganic nature, without supplementing them with a new and different force.

The forces of life are constructive forces, and they are operative in a world of destructive or disintegrating forces which oppose them and which they overcome. The physical and chemical forces of dead matter are at war with the forces of life, till life overcomes and uses them.

The mechanical forces go on repeating or dividing through the same cycles forever and ever, seeking a stable condition, but the vital force is inventive and creative and constantly breaks the repose that organic nature seeks to impose upon it.

External forces may modify a body, but they cannot develop it unless there is something in the body waiting to be developed, craving development, as it were. The warmth and moisture in the soil act alike upon the grains of sand and upon the seed-germs; the germ changes into something else, the sand does not. These agents liberate a force in the germ that is not in the grain of sand. The warmth of the brooding fowl does not spend itself upon mere passive, inert matter (unless there is a china egg in the nest), but upon matter straining upon its leash, and in a state of expectancy. We do not know how the activity of the molecules of the egg differs from the activity of the molecules of the pebble, under the influence of warmth, but we know there must be a difference between the interior movements of organized and unorganized matter.

Life lifts inert matter up into a thousand varied and beautiful forms and holds it there for a season,—holds it against gravity and chemical affinity, though you may say, if you please, not without their aid,—and then in due course lets go of it, or abandons it, and lets it fall back into the great sea of the inorganic. Its constant tendency is to fall back; indeed, in animal life it does fall back every moment; it rises on the one hand, serves its purpose of life, and falls back on the other. In going through the cycle of life the mineral elements experience some change that chemical analysis does not disclose—they are the more readily absorbed again by life. It is as if the elements had profited in some way under the tutelage of life. Their experience has been a unique and exceptional one. Only a small fraction of the sum total of the inert matter of the globe can have this experience. It must first go through the vegetable cycle before it can be taken up by the animal. The only things we can take directly from the inorganic world are water and air; and the function of water is largely a mechanical one, and the function of air a chemical one.

I think of the vital as flowing out of the physical, just as the psychical flows out of the vital, and just as the higher forms of animal life flow out of the lower. It is a far cry from man to the dumb brutes, and from the brutes to the vegetable world, and from the vegetable to inert matter; but the germ and start of each is in the series below it. The living came out of the not-living. If life is of physico-chemical origin, it is so by transformations and translations that physics cannot explain. The butterfly comes out of the grub, man came out of the brute, but, as Darwin says, "not by his own efforts," any more than the child becomes the man by its own efforts.

The push of life, of the evolutionary process, is back of all and in all. We can account for it all by saying the Creative Energy is immanent in matter, and this gives the mind something to take hold of.

II

According to the latest scientific views held on the question by such men as Professor Loeb, the appearance of life on the globe was a purely accidental circumstance. The proper elements just happened to come together at the right time in the right proportions and under the right conditions, and life was the result. It was an accident in the thermal history of the globe. Professor Loeb has lately published a volume of essays and addresses called "The Mechanistic Conception of Life," enforcing and illustrating this view. He makes war on what he terms the metaphysical conception of a "life-principle" as the key to the problem, and urges the scientific conception of the adequacy of mechanico-chemical forces. In his view, we are only chemical mechanisms; and all our activities, mental and physical alike, are only automatic responses to the play of the blind, material forces of external nature. All forms of life, with all their wonderful adaptations, are only the chance happenings of the blind gropings and clashings of dead matter: "We eat, drink, and reproduce [and, of course, think and speculate and write books on the problems of life], not because mankind has reached an agreement that this is desirable, but because, machine-like, we are compelled to do so!"

He reaches the conclusion that all our inner subjective life is amenable to physico-chemical analysis, because many cases of simple animal instinct and will can be explained on this basis—the basis of animal tropism. Certain animals creep or fly to the light, others to the dark, because they cannot help it. This is tropism. He believes that the origin of life can be traced to the same physico-chemical activities, because, in his laboratory experiments, he has been able to dispense with the male principle, and to fertilize the eggs of certain low forms of marine life by chemical compounds alone. "The problem of the beginning and end of individual life is physico-chemically clear"—much clearer than the first beginnings of life. All individual life begins with the egg, but where did we get the egg? When chemical synthesis will give us this, the problem is solved. We can analyze the material elements of an organism, but we cannot synthesize them and produce the least spark of living matter. That all forms of life have a mechanical and chemical basis is beyond question, but when we apply our analysis to them, life evaporates, vanishes, the vital processes cease. But apply the same analysis to inert matter, and only the form is changed.

Professor Loeb's artificially fathered embryo and starfish and sea-urchins soon die. If his chemism could only give him the mother-principle also! But it will not. The mother-principle is at the very foundations of the organic world, and defies all attempts of chemical synthesis to reproduce it.

It would be presumptive in the extreme for me to question Professor Loeb's scientific conclusions; he is one of the most eminent of living experimental biologists. I would only dissent from some of his philosophical conclusions. I dissent from his statement that only the mechanistic conception of life can throw light on the source of ethics. Is there any room for the moral law in a world of mechanical determinism? There is no ethics in the physical order, and if humanity is entirely in the grip of that order, where do moral obligations come in? A gun, a steam-engine, knows no ethics, and to the extent that we are compelled to do things, are we in the same category. Freedom of choice alone gives any validity to ethical consideration. I dissent from the idea to which he apparently holds, that biology is only applied physics and chemistry. Is not geology also applied physics and chemistry? Is it any more or any less? Yet what a world of difference between the two—between a rock and a tree, between a man and the soil he cultivates. Grant that the physical and the chemical forces are the same in both, yet they work to such different ends in each. In one case they are tending always to a deadlock, to the slumber of a static equilibrium; in the other they are ceaselessly striving to reach a state of dynamic activity—to build up a body that hangs forever between a state of integration and disintegration. What is it that determines this new mode and end of their activities?

In all his biological experimentation, Professor Loeb starts with living matter and, finding its processes capable of physico-chemical analysis, he hastens to the conclusion that its genesis is to be accounted for by the action and interaction of these principles alone.

In the inorganic world, everything is in its place through the operation of blind physical forces; because the place of a dead thing, its relation to the whole, is a matter of indifference. The rocks, the hills, the streams are in their place, but any other place would do as well. But in the organic world we strike another order—an order where the relation and subordination of parts is everything, and to speak of human existence as a "matter of chance" in the sense, let us say, that the forms and positions of inanimate bodies are matters of chance, is to confuse terms.

Organic evolution upon the earth shows steady and regular progression; as much so as the growth and development of a tree. If the evolutionary impulse fails on one line, it picks itself up and tries on another, it experiments endlessly like an inventor, but always improves on its last attempts. Chance would have kept things at a standstill; the principle of chance, give it time enough, must end where it began. Chance is a man lost in the woods; he never arrives; he wanders aimlessly. If evolution pursued a course equally fortuitous, would it not still be wandering in the wilderness of the chaotic nebulæ?

III

A vastly different and much more stimulating view of life is given by Henri Bergson in his "Creative Evolution." Though based upon biological science, it is a philosophical rather than a scientific view, and appeals to our intuitional and imaginative nature more than to our constructive reason. M. Bergson interprets the phenomena of life in terms of spirit, rather than in terms of matter as does Professor Loeb. The word "creative" is the key-word to his view. Life is a creative impulse or current which arose in matter at a certain time and place, and flows through it from form to form, from generation to generation, augmenting in force as it advances. It is one with spirit, and is incessant creation; the whole organic world is filled, from bottom to top, with one tremendous effort. It was long ago felicitously stated by Whitman in his "Leaves of Grass," "Urge and urge, always the procreant urge of the world."

This conception of the nature and genesis of life is bound to be challenged by modern physical science, which, for the most part, sees in biology only a phase of physics; but the philosophic mind and the trained literary mind will find in "Creative Evolution" a treasure-house of inspiring ideas, and engaging forms of original artistic expression. As Mr. Balfour says, "M. Bergson's 'Evolution Créatrice' is not merely a philosophical treatise, it has all the charm and all the audacities of a work of art, and as such defies adequate reproduction."

It delivers us from the hard mechanical conception of determinism, or of a closed universe which, like a huge manufacturing plant, grinds out vegetables and animals, minds and spirits, as it grinds out rocks and soils, gases and fluids, and the inorganic compounds.

With M. Bergson, life is the flowing metamorphosis of the poets,—an unceasing becoming,—and evolution is a wave of creative energy overflowing through matter "upon which each visible organism rides during the short interval of time given it to live." In his view, matter is held in the iron grip of necessity, but life is freedom itself. "Before the evolution of life ... the portals of the future remain wide open. It is a creation that goes on forever in virtue of an initial movement. This movement constitutes the unity of the organized world—a prolific unity, of an infinite richness, superior to any that the intellect could dream of, for the intellect is only one of its aspects or products."

What a contrast to Herbert Spencer's view of life and evolution! "Life," says Spencer, "consists of inner action so adjusted as to balance outer action." True enough, no doubt, but not interesting. If the philosopher could tell us what it is that brings about the adjustment, and that profits by it, we should at once prick up our ears. Of course, it is life. But what is life? It is inner action so adjusted as to balance outer action!

A recent contemptuous critic of M. Bergson's book, Hugh S. R. Elliot, points out, as if he were triumphantly vindicating the physico-chemical theory of the nature and origin of life, what a complete machine a cabbage is for converting solar energy into chemical and vital energy—how it takes up the raw material from the soil by a chemical and mechanical process, how these are brought into contact with the light and air through the leaves, and thus the cabbage is built up. In like manner, a man is a machine for converting chemical energy derived from the food he eats into motion, and the like. As if M. Bergson, or any one else, would dispute these things! In the same way, a steam-engine is a machine for converting the energy latent in coal into motion and power; but what force lies back of the engine, and was active in the construction?

The final question of the cabbage and the man still remains—Where did you get them?

You assume vitality to start with—how did you get it? Did it arise spontaneously out of dead matter? Mechanical and chemical forces do all the work of the living body, but who or what controls and directs them, so that one compounding of the elements begets a cabbage, and another compounding of the same elements begets an oak—one mixture of them and we have a frog, another and we have a man? Is there not room here for something besides blind, indifferent forces? If we make the molecules themselves creative, then we are begging the question. The creative energy by any other name remains the same.

IV

If life itself is not a force or a form of energy, yet behold what energy it is capable of exerting! It seems to me that Sir Oliver Lodge is a little confusing when he says in a recent essay that "life does not exert force—not even the most microscopical force—and certainly does not supply energy." Sir Oliver is thinking of life as a distinct entity—something apart from the matter which it animates. But even in this case can we not say that the mainspring of the energy of living bodies is the life that is in them?

Apart from the force exerted by living animal bodies, see the force exerted by living plant bodies. I thought of the remark of Sir Oliver one day not long after reading it, while I was walking in a beech wood and noted how the sprouting beechnuts had sent their pale radicles down through the dry leaves upon which they were lying, often piercing two or three of them, and forcing their way down into the mingled soil and leaf-mould a couple of inches. Force was certainly expended in doing this, and if the life in the sprouting nut did not exert it or expend it, what did?

When I drive a peg into the ground with my axe or mallet, is the life in my arm any more strictly the source (the secondary source) of the energy expended than is the nut in this case? Of course, the sun is the primal source of the energy in both cases, and in all cases, but does not life exert the force, use it, bring it to bear, which it receives from the universal fount of energy?

Life cannot supply energy de novo, cannot create it out of nothing, but it can and must draw upon the store of energy in which the earth floats as in a sea. When this energy or force is manifest through a living body, we call it vital force; when it is manifest through a mechanical contrivance, we call it mechanical force; when it is developed by the action and reaction of chemical compounds, we call it chemical force; the same force in each case, but behaving so differently in the one case from what it does in the other that we come to think of it as a new and distinct entity. Now if Sir Oliver or any one else could tell us what force is, this difference between the vitalists and the mechanists might be reconciled.

Darwin measured the force of the downward growth of the radicle, such as I have alluded to, as one quarter of a pound, and its lateral pressure as much greater. We know that the roots of trees insert themselves into seams in the rocks, and force the parts asunder. This force is measurable and is often very great. Its seat seems to be in the soft, milky substance called the cambium layer under the bark. These minute cells when their force is combined may become regular rock-splitters.

One of the most remarkable exhibitions of plant force I ever saw was in a Western city where I observed a species of wild sunflower forcing its way up through the asphalt pavement; the folded and compressed leaves of the plant, like a man's fist, had pushed against the hard but flexible concrete till it had bulged up and then split, and let the irrepressible plant through. The force exerted must have been many pounds. I think it doubtful if the strongest man could have pushed his fist through such a resisting medium. If it was not life which exerted this force, what was it? Life activities are a kind of explosion, and the slow continued explosions of this growing plant rent the pavement as surely as powder would have done. It is doubtful if any cultivated plant could have overcome such odds. It required the force of the untamed hairy plant of the plains to accomplish this feat.

That life does not supply energy, that is, is not an independent source of energy, seems to me obvious enough, but that it does not manifest energy, use energy, or "exert force," is far from obvious. If a growing plant or tree does not exert force by reason of its growing, or by virtue of a specific kind of activity among its particles, which we name life, and which does not take place in a stone or in a bar of iron or in dead timber, then how can we say that any mechanical device or explosive compound exerts force? The steam-engine does not create force, neither does the exploding dynamite, but these things exert force. We have to think of the sum total of the force of the universe, as of matter itself, as a constant factor, that can neither be increased nor diminished. All activity, organic and inorganic, draws upon this force: the plant and tree, as well as the engine and the explosive—the winds, the tides, the animal, the vegetable alike. I can think of but one force, but of any number of manifestations of force, and of two distinct kinds of manifestations, the organic and the inorganic, or the vital and the physical,—the latter divisible into the chemical and the mechanical, the former made up of these two working in infinite complexity because drawn into new relations, and lifted to higher ends by this something we call life.

We think of something in the organic that lifts and moves and redistributes dead matter, and builds it up into the ten thousand new forms which it would never assume without this something; it lifts lime and iron and silica and potash and carbon, against gravity, up into trees and animal forms, not by a new force, but by an old force in the hands of a new agent.

The cattle move about the field, the drift boulders slowly creep down the slopes; there is no doubt that the final source of the force is in both cases the same; what we call gravity, a name for a mystery, is the form it takes in the case of the rocks, and what we call vitality, another name for a mystery, is the form it takes in the case of the cattle; without the solar and stellar energy, could there be any motion of either rock or beast?

Force is universal, it pervades all nature, one manifestation of it we call heat, another light, another electricity, another cohesion, chemical affinity, and so on. May not another manifestation of it be called life, differing from all the rest more radically than they differ from one another; bound up with all the rest and inseparable from them and identical with them only in its ultimate source in the Creative Energy that is immanent in the universe? I have to think of the Creative Energy as immanent in all matter, and the final source of all the transformations and transmutations we see in the organic and the inorganic worlds. The very nature of our minds compels us to postulate some power, or some principle, not as lying back of, but as active in, all the changing forms of life and nature, and their final source and cause.

The mind is satisfied when it finds a word that gives it a hold of a thing or a process, or when it can picture to itself just how the thing occurs. Thus, for instance, to account for the power generated by the rushing together of hydrogen and oxygen to produce water, we have to conceive of space between the atoms of these elements, and that the force generated comes from the immense velocity with which the infinitesimal atoms rush together across this infinitesimal space. It is quite possible that this is not the true explanation at all, but it satisfies the mind because it is an explanation in terms of mechanical forces that we know.

The solar energy goes into the atoms or corpuscles one thing, and it comes out another; it goes in as inorganic force, and it comes out as organic and psychic. The change or transformation takes place in those invisible laboratories of the infinitesimal atoms. It helps my mental processes to give that change a name—vitality—and to recognize it as a supra-mechanical force. Pasteur wanted a name for it and called it "dissymmetric force."

We are all made of one stuff undoubtedly, vegetable and animal, man and woman, dog and donkey, and the secret of the difference between us, and of the passing along of the difference from generation to generation with but slight variations, may be, so to speak, in the way the molecules and atoms of our bodies take hold of hands and perform their mystic dances in the inner temple of life. But one would like to know who or what pipes the tune and directs the figures of the dance.

In the case of the beechnuts, what is it that lies dormant in the substance of the nuts and becomes alive, under the influence of the warmth and moisture of spring, and puts out a radicle that pierces the dry leaves like an awl? The pebbles, though they contain the same chemical elements, do not become active and put out a radicle.

The chemico-physical explanation of the universe goes but a little way. These are the tools of the creative process, but they are not that process, nor its prime cause. Start the flame of life going, and the rest may be explained in terms of chemistry; start the human body developing, and physiological processes explain its growth; but why it becomes a man and not a monkey—what explains that?

II

THE LIVING WAVE

I

If one attempts to reach any rational conclusion on the question of the nature and origin of life on this planet, he soon finds himself in close quarters with two difficulties. He must either admit of a break in the course of nature and the introduction of a new principle, the vital principle, which, if he is a man of science, he finds it hard to do; or he must accept the theory of the physico-chemical origin of life, which, as a being with a soul, he finds it equally hard to do. In other words, he must either draw an arbitrary line between the inorganic and the organic when he knows that drawing arbitrary lines in nature, and fencing off one part from another, is an unscientific procedure, and one that often leads to bewildering contradictions; or he must look upon himself with all his high thoughts and aspirations, and upon all other manifestations of life, as merely a chance product of the blind mechanical and chemical action and interaction of the inorganic forces.

Either conclusion is distasteful. One does not like to think of himself as a chance hit of the irrational physical elements; neither does he feel at ease with the thought that he is the result of any break or discontinuity in natural law. He likes to see himself as vitally and inevitably related to the physical order as is the fruit to the tree that bore it, or the child to the mother that carried it in her womb, and yet, if only mechanical and chemical forces entered into his genesis, he does not feel himself well fathered and mothered.

One may evade the difficulty, as Helmholtz did, by regarding life as eternal—that it had no beginning in time; or, as some other German biologists have done, that the entire cosmos is alive and the earth a living organism.

If biogenesis is true, and always has been true,—no life without antecedent life,—then the question of a beginning is unthinkable. It is just as easy to think of a stick with only one end.

Such stanch materialists and mechanists as Haeckel and Verworn seem to have felt compelled, as a last resort, to postulate a psychic principle in nature, though of a low order. Haeckel says that most chemists and physicists will not hear a word about a "soul" in the atom. "In my opinion, however," he says, "in order to explain the simplest physical and chemical processes, we must necessarily assume a low order of psychical activity among the homogeneous particles of plasm, rising a very little above that of the crystal." In crystallization he sees a low degree of sensation and a little higher degree in the plasm.

Have we not in this rudimentary psychic principle which Haeckel ascribes to the atom a germ to start with that will ultimately give us the mind of man? With this spark, it seems to me, we can kindle a flame that will consume Haeckel's whole mechanical theory of creation. Physical science is clear that the non-living or inorganic world was before the living or organic world, but that the latter in some mysterious way lay folded in the former. Science has for many years been making desperate efforts to awaken this slumbering life in its laboratories, but has not yet succeeded, and probably never will succeed. Life without antecedent life seems a biological impossibility. The theory of spontaneous generation is rejected by the philosophical mind, because our experience tells us that everything has its antecedent, and that there is and can be no end to the causal sequences.

Spencer believes that the organic and inorganic fade into each other by insensible gradations—that no line can be drawn between them so that one can say, on this side is the organic, on that the inorganic. In other words, he says it is not necessary for us to think of an absolute commencement of organic life, or of a first organism—organic matter was not produced all at once, but was reached through steps or gradations. Yet it puzzles one to see how there can be any gradations or degrees between being and not being. Can there be any halfway house between something and nothing?

II

There is another way out of the difficulty that besets our rational faculties in their efforts to solve this question, and that is the audacious way of Henri Bergson in his "Creative Evolution." It is to deny any validity to the conclusion of our logical faculties upon this subject. Our intellect, Bergson says, cannot grasp the true nature of life, nor the meaning of the evolutionary movement. With the emphasis of italics he repeats that "the intellect is characterized by a natural inability to comprehend life." He says this in a good many pages and in a good many different ways; the idea is one of the main conclusions of his book. Our intuitions, our spiritual nature, according to this philosopher, are more en rapport with the secrets of the creative energy than are our intellectual faculties; the key to the problem is to be found here, rather than in the mechanics and chemistry of the latter. Our intellectual faculties can grasp the physical order because they are formed by a world of solids and fluids and give us the power to deal with them and act upon them. But they cannot grasp the nature and the meaning of the vital order.

"We treat the living like the lifeless, and think all reality, however fluid, under the form of the sharply defined solid. We are at ease only in the discontinuous, in the immobile, in the dead. Perceiving in an organism only parts external to parts, the understanding has the choice between two systems of explanation only: either to regard the infinitely complex (and thereby infinitely well contrived) organization as a fortuitous concatenation of atoms, or to relate it to the incomprehensible influence of an external force that has grouped its elements together."

"Everything is obscure in the idea of creation, if we think of things which are created and a thing which creates." If we follow the lead of our logical, scientific faculties, then, we shall all be mechanists and materialists. Science can make no other solution of the problem because it sees from the outside. But if we look from the inside, with the spirit or "with that faculty of seeing which is immanent in the faculty of acting," we shall escape from the bondage of the mechanistic view into the freedom of the larger truth of the ceaseless creative view; we shall see the unity of the creative impulse which is immanent in life and which, "passing through generations, links individuals with individuals, species with species, and makes of the whole series of the living one single immense wave flowing over matter."

I recall that Tyndall, who was as much poet as scientist, speaks of life as a wave "which at no two consecutive moments of its existence is composed of the same particles." In his more sober scientific mood Tyndall would doubtless have rejected M. Bergson's view of life, yet his image of the wave is very Bergsonian. But what different meanings the two writers aim to convey: Tyndall is thinking of the fact that a living body is constantly taking up new material on the one side and dropping dead or outworn material on the other. M. Bergson's mind is occupied with the thought of the primal push or impulsion of matter which travels through it as the force in the wave traverses the water. The wave embodies a force which lifts the water up in opposition to its tendency to seek and keep a level, and travels on, leaving the water behind. So does this something we call life break the deadlock of inert matter and lift it into a thousand curious and beautiful forms, and then, passing on, lets it fall back again into a state of dead equilibrium.

Tyndall was one of the most eloquent exponents of the materialistic theory of the origin of life, and were he living now would probably feel little or no sympathy with the Bergsonian view of a primordial life impulse. He found the key to all life phenomena in the hidden world of molecular attraction and repulsion. He says: "Molecular forces determine the form which the solar energy will assume. [What a world of mystery lies in that determinism of the hidden molecular forces!] In the separation of the carbon and oxygen this energy may be so conditioned as to result in one case in the formation of a cabbage and in another case in the formation of an oak. So also as regards the reunion of the carbon and the oxygen [in the animal organism] the molecular machinery through which the combining energy acts may in one case weave the texture of a frog, while in another it may weave the texture of a man."

But is not this molecular force itself a form of solar energy, and can it differ in kind from any other form of physical force? If molecular forces determine whether the solar energy shall weave a head of a cabbage or a head of a Plato or a Shakespeare, does it not meet all the requirements of our conception of creative will?

Tyndall thinks that a living man—Socrates, Aristotle, Goethe, Darwin, I suppose—could be produced directly from inorganic nature in the laboratory if (and note what a momentous "if" this is) we could put together the elements of such a man in the same relative positions as those which they occupy in his body, "with the selfsame forces and distribution of forces, the selfsame motions and distribution of motions." Do this and you have a St. Paul or a Luther or a Lincoln. Dr. Verworn said essentially the same thing in a lecture before one of our colleges while in this country a few years ago—easy enough to manufacture a living being of any order of intellect if you can reproduce in the laboratory his "internal and external vital conditions." (The italics are mine.) To produce those vital conditions is where the rub comes. Those vital conditions, as regards the minutest bit of protoplasm, science, with all her tremendous resources, has not yet been able to produce. The raising of Lazarus from the dead seems no more a miracle than evoking vital conditions in dead matter. External and internal vital conditions are no doubt inseparably correlated, and when we can produce them we shall have life. Life, says Verworn, is like fire, and "is a phenomenon of nature which appears as soon as the complex of its conditions is fulfilled." We can easily produce fire by mechanical and chemical means, but not life. Fire is a chemical process, it is rapid oxidation, and oxidation is a disintegrating process, while life is an integrating process, or a balance maintained between the two by what we call the vital force. Life is evidently a much higher form of molecular activity than combustion. The old Greek Heraclitus saw, and the modern scientist sees, very superficially in comparing the two.

I have no doubt that Huxley was right in his inference "that if the properties of matter result from the nature and disposition of its component molecules, then there is no intelligible ground for refusing to say that the properties of protoplasm result from the nature and disposition of its molecules." It is undoubtedly in that nature and disposition of the biological molecules that Tyndall's whole "mystery and miracle of vitality" is wrapped up. If we could only grasp what it is that transforms the molecule of dead matter into the living molecule! Pasteur called it "dissymmetric force," which is only a new name for the mystery. He believed there was an "irrefragable physical barrier between organic and inorganic nature"—that the molecules of an organism differed from those of a mineral, and for this difference he found a name.

III

There seems to have been of late years a marked reaction, even among men of science, from the mechanistic conception of life as held by the band of scientists to which I have referred. Something like a new vitalism is making headway both on the Continent and in Great Britain. Its exponents urge that biological problems "defy any attempt at a mechanical explanation." These men stand for the idea "of the creative individuality of organisms" and that the main factors in organic evolution cannot be accounted for by the forces already operative in the inorganic world.

There is, of course, a mathematical chance that in the endless changes and permutations of inert matter the four principal elements that make up a living body may fall or run together in just that order and number that the kindling of the flame of life requires, but it is a disquieting proposition. One atom too much or too little of any of them,—three of oxygen where two were required, or two of nitrogen where only one was wanted,—and the face of the world might have been vastly different. Not only did much depend on their coming together, but upon the order of their coming; they must unite in just such an order. Insinuate an atom or corpuscle of hydrogen or carbon at the wrong point in the ranks, and the trick is a failure. Is there any chance that they will hit upon a combination of things and forces that will make a machine—a watch, a gun, or even a row of pins?

When we regard all the phenomena of life and the spell it seems to put upon inert matter, so that it behaves so differently from the same matter before it is drawn into the life circuit, when we see how it lifts up a world of dead particles out of the soil against gravity into trees and animals; how it changes the face of the earth; how it comes and goes while matter stays; how it defies chemistry and physics to evoke it from the non-living; how its departure, or cessation, lets the matter fall back to the inorganic—when we consider these and others like them, we seem compelled to think of life as something, some force or principle in itself, as M. Bergson and Sir Oliver Lodge do, existing apart from the matter it animates.

Sir Oliver Lodge, famous physicist that he is, yet has a vein of mysticism and idealism in him which sometimes makes him recoil from the hard-and-fast interpretations of natural phenomena by physical science. Like M. Bergson, he sees in life some tendency or impetus which arose in matter at a definite time and place, "and which has continued to interact with and incarnate itself in matter ever since."

If a living body is a machine, then we behold a new kind of machine with new kinds of mechanical principles—a machine that repairs itself, that reproduces itself, a clock that winds itself up, an engine that stokes itself, a gun that aims itself, a machine that divides and makes two, two unite and make four, a million or more unite and make a man or a tree—a machine that is nine tenths water, a machine that feeds on other machines, a machine that grows stronger with use; in fact, a machine that does all sorts of unmechanical things and that no known combination of mechanical and chemical principles can reproduce—a vital machine. The idea of the vital as something different from and opposed to the mechanical must come in. Something had to be added to the mechanical and chemical to make the vital.

Spencer explains in terms of physics why an ox is larger than the sheep, but he throws no light upon the subject of the individuality of these animals—what it is that makes an ox an ox or a sheep a sheep. These animals are built up out of the same elements by the same processes, and they may both have had the same stem form in remote biologic time. If so, what made them diverge and develop into such totally different forms? After the living body is once launched many, if not all, of its operations and economies can be explained on principles of mechanics and chemistry, but the something that avails itself of these principles and develops an ox in the one case and a sheep in the other—what of that?

Spencer is forced into using the terms "amount of vital capital." How much more of it some men, some animals, some plants have than others! What is it? What did Spencer mean by it? This capital augments from youth to manhood, and then after a short or long state of equilibrium slowly declines to the vanishing-point.

Again, what a man does depends upon what he is, and what he is depends upon what he does. Structure determines function, and function reacts upon structure. This interaction goes on throughout life; cause and effect interchange or play into each other's hands. The more power we spend within limits the more power we have. This is another respect in which life is utterly unmechanical. A machine does not grow stronger by use as our muscles do; it does not store up or conserve the energy it expends. The gun is weaker by every ball it hurls; not so the baseball pitcher; he is made stronger up to the limit of his capacity for strength.

It is plain enough that all living beings are machines in this respect—they are kept going by the reactions between their interior and their exterior; these reactions are either mechanical, as in flying, swimming, walking, and involve gravitation, or they are chemical and assimilative, as in breathing and eating. To that extent all living things are machines—some force exterior to themselves must aid in keeping them going; there is no spontaneous or uncaused movement in them; and yet what a difference between a machine and a living thing!

True it is that a man cannot live and function without heat and oxygen, nor long without food, and yet his relation to his medium and environment is as radically different from that of the steam-engine as it is possible to express. His driving-wheel, the heart, acts in response to some stimulus as truly as does the piston of the engine, and the principles involved in circulation are all mechanical; and yet the main thing is not mechanical, but vital. Analyze the vital activities into principles of mechanics and of chemistry, if you will, yet there is something involved that is neither mechanical nor chemical, though it may be that only the imagination can grasp it.

The type that prints the book is set up and again distributed by a purely mechanical process, but that which the printed page signifies involves something not mechanical. The mechanical and chemical principles operative in men's bodies are all the same; the cell structure is the same, and yet behold the difference between men in size, in strength, in appearance, in temperament, in disposition, in capacities! All the processes of respiration, circulation, and nutrition in our bodies involve well-known mechanical principles, and the body is accurately described as a machine; and yet if there were not something in it that transcends mechanics and chemistry would you and I be here? A machine is the same whether it is in action or repose, but when a body ceases to function, it is not the same. It cannot be set going like a machine; the motor power has ceased to be. But if the life of the body were no more than the sum of the reactions existing between the body and the medium in which it lives, this were not so. A body lives as long as there is a proper renewal of the interior medium through exchanges with its environment.

Mechanical principles are operative in every part of the body—in the heart, in the arteries, in the limbs, in the joints, in the bowels, in the muscles; and chemical principles are operative in the lungs, in the stomach, in the liver, in the kidneys; but to all these things do we not have to add something that is not mechanical or chemical to make the man, to make the plant? A higher mechanics, a higher chemistry, if you prefer, a force, but a force differing in kind from the physical forces.

The forces of life are constructive forces, and work in a world of disintegrating or destructive forces which oppose them and which they overcome. The mechanical and the chemical forces of dead matter are the enemies of the forces of life till life overcomes and uses them; as much so as gravity, fire, frost, water are man's enemies till he has learned how to subdue and use them.

IV

It is a significant fact that the four chief elements which in various combinations make up living bodies are by their extreme mobility well suited to their purpose. Three of these are gaseous; only the carbon is a solid. This renders them facile and adaptive in the ever-changing conditions of organic evolution. The solid carbon forms the vessel in which the precious essence of life is carried. Without carbon we should evaporate or flow away and escape. Much of the oxygen and hydrogen enters into living bodies as water; nine tenths of the human body is water; a little nitrogen and a few mineral salts make up the rest. So that our life in its final elements is little more than a stream of water holding in solution carbonaceous and other matter and flowing, forever flowing, a stream of fluid and solid matter plus something else that scientific analysis cannot reach—some force or principle that combines and organizes these elements into the living body.

If a man could be reduced instantly into his constituent elements we should see a pail or two of turbid fluid that would flow down the bank and soon be lost in the soil. That which gives us our form and stability and prevents us from slowly spilling down the slope at all times is the mysterious vital principle or force which knits and marries these unstable elements together and raises up a mobile but more or less stable form out of the world of fluids. Venus rising from the sea is a symbol of the genesis of every living thing.

Inorganic matter seeks only rest. "Let me alone," it says; "do not break my slumbers." But as soon as life awakens in it, it says: "Give me room, get out of my way. Ceaseless activity, ceaseless change, a thousand new forms are what I crave." As soon as life enters matter, matter meets with a change of heart. It is lifted to another plane, the supermechanical plane; it behaves in a new way; its movements from being calculable become incalculable. A straight line has direction, that is mechanics; what direction has the circle? That is life, a change of direction every instant. An aeroplane is built entirely on mechanical principles, but something not so built has to sit in it and guide it; in fact, had to build it and adjust it to its end.

Mechanical forces seek an equilibrium or a state of rest. The whole inorganic world under the influence of gravity would flow as water flows, if it could, till it reached a state of absolute repose. But vital forces struggle against a state of repose, which to them means death. They are vital by virtue of their tendency to resist the repose of inert matter; chemical activity disintegrates a stone or other metal, but the decay of organized matter is different in kind; living organisms decompose it and resolve it into its original compounds.

Vital connections and mechanical connections differ in kind. You can treat mechanical principles mathematically, but can you treat life mathematically? Will your formulas and equations apply here? You can figure out the eclipses of the sun and moon for centuries to come, but who can figure out the eclipses of nations or the overthrow of parties or the failures of great men? And it is not simply because the problem is so vastly more complex; it is because you are in a world where mathematical principles do not apply. Mechanical forces will determine the place and shape of every particle of inert matter any number of years or centuries hence, but they will not determine the place and condition of matter imbued with the principle of life.

We can graft living matter, we can even graft a part of one animal's body into another animal's body, but the mechanical union which we bring about must be changed into vital union to be a success, the spirit of the body has to second our efforts. The same in grafting a tree or anything else: the mechanical union which we effect must become a vital union; and this will not take place without some degree of consanguinity, the live scion must be recognized and adapted by the stock in which we introduce it.

Living matter may be symbolized by a stream; it is ever and never the same; life is a constant becoming; our minds and our bodies are never the same at any two moments of time; life is ceaseless change.

No doubt it is between the stable and the unstable condition of the molecules of matter that life is born. The static condition to which all things tend is death. Matter in an unstable condition tends either to explode or to grow or to disintegrate. So that an explosion bears some analogy to life, only it is quickly over and the static state of the elements is restored. Life is an infinitely slower explosion, or a prolonged explosion, during which some matter of the organism is being constantly burned up, and thus returned to a state of inorganic repose, while new matter is taken in and kindled and consumed by the fires of life. One can visualize all this and make it tangible to the intellect. Get your fire of life started and all is easy, but how to start it is the rub. Get your explosive compound, and something must break the deadlock of the elements before it will explode. So in life, what is it that sets up this slow gentle explosion that makes the machinery of our vital economies go—that draws new matter into the vortex and casts the used-up material out—in short, that creates and keeps up the unstable condition, the seesaw upon which life depends? To enable the mind to grasp it we have to invent or posit some principle, call it the vital force, as so many have done and still do, or call it molecular force, as Tyndall does, or the power of God, as our orthodox brethren do, it matters not. We are on the border-land between the knowable and the unknowable, where the mind can take no further step. There is no life without carbon and oxygen, hydrogen and nitrogen, but there is a world of these elements without life. What must be added to them to set up the reaction we call life? Nothing that chemistry can disclose.

New tendencies and activities are set up among these elements, but the elements themselves are not changed; oxygen is still oxygen and carbon still carbon, yet behold the wonder of their new workmanship under the tutelage of life!

Life only appears when the stable passes into the unstable, yet this change takes place all about us in our laboratories, and no life appears. We can send an electric spark through a room full of oxygen and hydrogen gas, and with a tremendous explosion we have water—an element of life, but not life.

Some of the elements seem nearer life than others. Water is near life; heat, light, the colloid state are near life; osmosis, oxidation, chemical reactions are near life; the ashes of inorganic bodies are nearer life than the same minerals in the rocks and soil; but none of these things is life.

The chemical mixture of some of the elements gives us our high explosives—gunpowder, guncotton, and the like; their organic mixture gives a slower kind of explosive—bread, meat, milk, fruit, which, when acted upon by the vital forces of the body, yield the force that is the equivalent of the work the body does. But to combine them in the laboratory so as to produce the compounds out of which the body can extract force is impossible. We can make an unstable compound that will hurl a ton of iron ten miles, but not one that when exploded in the digestive tract of the human body will lift a hair.

We may follow life down to the ground, yes, under the ground, into the very roots of matter and motion, yea, beyond the roots, into the imaginary world of molecules and atoms, and their attractions and repulsions and not find its secret. Indeed, science—the new science—pursues matter to the vanishing-point, where it ceases to become matter and becomes pure force or spirit. What takes place in that imaginary world where ponderable matter ends and becomes disembodied force, and where the hypothetical atoms are no longer divisible, we may conjecture but may never know. We may fancy the infinitely little going through a cycle of evolution like that of the infinitely great, and solar systems developing and revolving inside of the ultimate atoms, but the Copernicus or the Laplace of the atomic astronomy has not yet appeared. The atom itself is an invention of science. To get the mystery of vitality reduced to the atom is getting it in very close quarters, but it is a very big mystery still. Just how the dead becomes alive, even in the atom, is mystery enough to stagger any scientific mind. It is not the volume of the change; it is the quality or kind. Chemistry and mechanics we have always known, and they always remain chemistry and mechanics. They go into our laboratories and through our devices chemistry and mechanics, and they come out chemistry and mechanics. They will never come out life, conjure with them as we will, and we can get no other result. We cannot inaugurate the mystic dance among the atoms that will give us the least throb of life.

The psychic arises out of the organic and the organic arises out of the inorganic, and the inorganic arises out of—what? The relation of each to the other is as intimate as that of the soul to the body; we cannot get between them even in thought, but the difference is one of kind and not of degree. The vital transcends the mechanical, and the psychic transcends the vital—is on another plane, and yet without the sun's energy there could be neither. Thus are things knit together; thus does one thing flow out of or bloom out of another. We date from the rocks, and the rocks date from the fiery nebulæ, and the loom in which the texture of our lives was woven is the great loom of vital energy about us and in us; but what hand guided the shuttle and invented the pattern—who knows?

III

A WONDERFUL WORLD

I

Science recognizes a more fundamental world than that of matter. This is the electro-magnetic world which underlies the material world and which, as Professor Soddy says, probably completely embraces it, and has no mechanical analogy. To those accustomed only to the grosser ideas of matter and its motions, says the British scientist, this electro-magnetic world is as difficult to conceive of as it would be for us to walk upon air. Yet many times in our lives is this world in overwhelming evidence before us. During a thunderstorm we get an inkling of how fearfully and wonderfully the universe in which we live is made, and what energy and activity its apparent passivity and opacity mark. A flash of lightning out of a storm-cloud seems instantly to transform the whole passive universe into a terrible living power. This slow, opaque, indifferent matter about us and above us, going its silent or noisy round of mechanical and chemical change, ponderable, insensate, obstructive, slumbering in the rocks, quietly active in the soil, gently rustling in the trees, sweetly purling in the brooks, slowly, invisibly building and shaping our bodies—how could we ever dream that it held in leash such a terrible, ubiquitous, spectacular thing as this of the forked lightning? If we were to see and hear it for the first time, should we not think that the Judgment Day had really come? that the great seals of the Book of Fate were being broken?

What an awakening it is! what a revelation! what a fearfully dramatic actor suddenly leaps upon the stage! Had we been permitted to look behind the scenes, we could not have found him; he was not there, except potentially; he was born and equipped in a twinkling. One stride, and one word which shakes the house, and he is gone; gone as quickly as he came. Look behind the curtain and he is not there. He has vanished more completely than any stage ghost ever vanished—he has withdrawn into the innermost recesses of the atomic structure of matter, and is diffused through the clouds, to be called back again, as the elemental drama proceeds, as suddenly as before.

All matter is charged with electricity, either actual or potential; the sun is hot with it, and doubtless our own heart-beats, our own thinking brains, are intimately related to it; yet it is palpable and visible only in this sudden and extraordinary way. It defies our analysis, it defies our definitions; it is inscrutable and incomprehensible, yet it will do our errands, light our houses, cook our dinners, and pull our loads.

How humdrum and constant and prosaic the other forces—gravity, cohesion, chemical affinity, and capillary attraction—seem when compared with this force of forces, electricity! How deep and prolonged it slumbers at one time, how terribly active and threatening at another, bellowing through the heavens like an infuriated god seeking whom he may destroy!

The warring of the elements at such times is no figure of speech. What has so disturbed the peace in the electric equilibrium, as to make possible this sudden outburst, this steep incline in the stream of energy, this ethereal Niagara pouring from heaven to earth? Is a thunderstorm a display of the atomic energy of which the physicists speak, and which, were it available for our use, would do all the work of the world many times over?

How marvelous that the softest summer breeze, or the impalpable currents of the calmest day, can be torn asunder with such suddenness and violence, by the accumulated energy that slumbers in the imaginary atoms, as to give forth a sound like the rending of mountains or the detonations of earthquakes!

Electricity is the soul of matter. If Whitman's paradox is true, that the soul and body are one, in the same sense the scientific paradox is true: that matter and electricity are one, and both are doubtless a phase of the universal ether—a reality which can be described only in terms of the negation of matter. In a flash of lightning we see pure disembodied energy—probably that which is the main-spring of the universe. Modern science is more and more inclined to find the explanation of all vital phenomena in electrical stress and change. We know that an electric current will bring about chemical changes otherwise impracticable. Nerve force, if not a form of electricity, is probably inseparable from it. Chemical changes equivalent to the combustion of fuel and the corresponding amount of available energy released have not yet been achieved outside of the living body without great loss. The living body makes a short cut from fuel to energy, and this avoids the wasteful process of the engine. What part electricity plays in this process is, of course, only conjectural.

II

Our daily lives go on for the most part in two worlds, the world of mechanical transposition and the world of chemical transformations, but we are usually conscious only of the former. This is the visible, palpable world of motion and change that rushes and roars around us in the winds, the storms, the floods, the moving and falling bodies, and the whole panorama of our material civilization; the latter is the world of silent, invisible, unsleeping, and all-potent chemical reactions that take place all about us and is confined to the atoms and molecules of matter, as the former is confined to its visible aggregates.

Mechanical forces and chemical affinities rule our physical lives, and indirectly our psychic lives as well. When we come into the world and draw our first breath, mechanics and chemistry start us on our career. Breathing is a mechanical, or a mechanico-vital, act; the mechanical principle involved is the same as that involved in the working of a bellows, but the oxidation of the blood when the air enters the lungs is a chemical act, or a chemico-vital act. The air gives up a part of its oxygen, which goes into the arterial circulation, and its place is taken by carbonic-acid gas and watery vapor. The oxygen feeds and keeps going the flame of life, as literally as it feeds and keeps going the fires in our stoves and furnaces.

Hence our most constant and vital relation to the world without is a chemical one. We can go without food for some days, but we can exist without breathing only a few moments. Through these spongy lungs of ours we lay hold upon the outward world in the most intimate and constant way. Through them we are rooted to the air. The air is a mechanical mixture of two very unlike gases—nitrogen and oxygen; one very inert, the other very active. Nitrogen is like a cold-blooded, lethargic person—it combines with other substances very reluctantly and with but little energy. Oxygen is just its opposite in this respect: it gives itself freely; it is "Hail, fellow; well met!" with most substances, and it enters into co-partnership with them on such a large scale that it forms nearly one half of the material of the earth's crust. This invisible gas, this breath of air, through the magic of chemical combination, forms nearly half the substance of the solid rocks. Deprive it of its affinity for carbon, or substitute nitrogen or hydrogen in its place, and the air would quickly suffocate us. That changing of the dark venous blood in our lungs into the bright, red, arterial blood would instantly cease. Fancy the sensation of inhaling an odorless, non-poisonous atmosphere that would make one gasp for breath! We should be quickly poisoned by the waste of our own bodies. All things that live must have oxygen, and all things that burn must have oxygen. Oxygen does not burn, but it supports combustion.

And herein is one of the mysteries of chemistry again. This support which the oxygen gives is utterly unlike any support we are acquainted with in the world of mechanical forces. Oxygen supports combustion by combining chemically with carbon, and the evolution of heat and light is the result. And this is another mystery—this chemical union which takes place in the ultimate particles of matter and which is so radically different from a mechanical mixture. In a chemical union the atoms are not simply in juxtaposition; they are, so to speak, inside of one another—each has swallowed another and lost its identity, an impossible feat, surely, viewed in the light of our experiences with tangible bodies. In the visible, mechanical world no two bodies can occupy the same place at the same time, but apparently in chemistry they can and do. An atom of oxygen and one of carbon, or of hydrogen, unite and are lost in each other; it is a marriage wherein the two or three become one. In dealing with the molecules and atoms of matter we are in a world wherein the laws of solid bodies do not apply; friction is abolished, elasticity is perfect, and place and form play no part. We have escaped from matter as we know it, the solid, fluid, or gaseous forms, and are dealing with it in its fourth or ethereal estate. In breathing, the oxygen goes into the blood, not to stay there, but to unite with and bring away the waste of the system in the shape of carbon, and re-enter the air again as one of the elements of carbonic-acid gas, CO2. Then the reverse process takes place in the vegetable world, the leaves breathe this poisonous gas, release the oxygen under the chemistry of the sun's rays, and appropriate and store up the carbon. Thus do the animal and vegetable worlds play into each other's hands. The animal is dependent upon the vegetable for its carbon, which it releases again, through the life processes, as carbonic-acid gas, to be again drawn into the cycle of vegetable life.

The act of breathing well illustrates our mysterious relations to Nature—the cunning way in which she plays the principal part in our lives without our knowledge. How certain we are that we draw the air into our lungs—that we seize hold of it in some way as if it were a continuous substance, and pull it into our bodies! Are we not also certain that the pump sucks the water up through the pipe, and that we suck our iced drinks through a straw? We are quite unconscious of the fact that the weight of the superincumbent air does it all, that breathing is only to a very limited extent a voluntary act. It is controlled by muscular machinery, but that machinery would not act in a vacuum. We contract the diaphragm, or the diaphragm contracts under stimuli received through the medulla oblongata from those parts of the body which constantly demand oxygen, and a vacuum tends to form in the chest, which is constantly prevented by the air rushing in to fill it. The expansive force of the air under its own weight causes the lungs to fill, just as it causes the bellows of the blacksmith to fill when he works the lever, and the water to rise in the pump when we force out the air by working the handle. Another unconscious muscular effort under the influence of nerve stimulus, and the air is forced out of the lungs, charged with the bodily waste which it is the function to relieve. But the wonder of it all is how slight a part our wills play in the process, and how our lives are kept going by a mechanical force from without, seconded or supplemented by chemical and vital forces from within.

The one chemical process with which we are familiar all our lives, but which we never think of as such, is fire. Here on our own hearthstones goes on this wonderful spectacular and beneficent transformation of matter and energy, and yet we are grown so familiar with it that it moves us not. We can describe combustion in terms of chemistry, just as we can describe the life-processes in similar terms, yet the mystery is no more cleared up in the one case than in the other. Indeed, it seems to me that next to the mystery of life is the mystery of fire. The oxidizing processes are identical, only one is a building up or integrating process, and the other is a pulling down or disintegrating process. More than that, we can evoke fire any time, by both mechanical and chemical means, from the combustible matter about us; but we cannot evoke life. The equivalents of life do not slumber in our tools as do the equivalents of fire. Hence life is the deeper mystery. The ancients thought of a spirit of fire as they did of a spirit of health and of disease, and of good and bad spirits all about them, and as we think of a spirit of life, or of a creative life principle. Are we as wide of the mark as they were? So think many earnest students of living things. When we do not have to pass the torch of life along, but can kindle it in our laboratories, then this charge will assume a different aspect.

III

Nature works with such simple means! A little more or a little less of this or that, and behold the difference! A little more or a little less heat, and the face of the world is changed.

"And the little more, and how much it is,

And the little less, and what worlds away!"

At one temperature water is solid, at another it is fluid, at another it is a visible vapor, at a still higher it is an invisible vapor that burns like a flame. All possible shades of color lurk in a colorless ray of light. A little more or a little less heat makes all the difference between a nebula and a sun, and between a sun and a planet. At one degree of heat the elements are dissociated; at a lower degree they are united. At one point in the scale of temperatures life appears; at another it disappears. With heat enough the earth would melt like a snowball in a furnace, with still more it would become a vapor and float away like a cloud. More or less heat only makes the difference between the fluidity of water and the solidity of the rocks that it beats against, or of the banks that hold it.

The physical history of the universe is written in terms of heat and motion. Astronomy is the story of cooling suns and worlds. At a low enough temperature all chemical activity ceases. In our own experience we find that frost will blister like flame. In the one case heat passes into the tissues so quickly and in such quantity that a blister ensues; in the other, heat is abstracted so quickly and in such quantity that a like effect is produced. In one sense, life is a thermal phenomenon; so are all conditions of fluids and solids thermal phenomena.

Great wonders Nature seems to achieve by varying the arrangement of the same particles. Arrange or unite the atoms of carbon in one way and you have charcoal; assemble the same atoms in another order, and you have the diamond. The difference between the pearl and the oyster-shell that holds it is one of structure or arrangement of the same particles of matter. Arrange the atoms of silica in one way and you have a quartz pebble, in another way and you have a precious stone. The chemical constituents of alcohol and ether are the same; the difference in their qualities and properties arises from the way the elements are compounded—the way they take hold of hands, so to speak, in that marriage ceremony which constitutes a chemical compound. Compounds identical in composition and in molecular formulæ may yet differ widely in physical properties; the elements are probably grouped in different ways, the atoms of carbon or of hydrogen probably carry different amounts of potential energy, so that the order in which they stand related to one another accounts for the different properties of the same chemical compounds. Different groupings of the same atoms of any of the elements result in a like difference of physical properties.

The physicists tell us that what we call the qualities of things, and their structure and composition, are but the expressions of internal atomic movements. A complex substance simply means a whirl, an intricate dance, of which chemical composition, histological structure, and gross configuration are the figures. How the atoms take hold of hands, as it were, the way they face, the poses they assume, the speed of their gyrations, the partners they exchange, determine the kinds of phenomena we are dealing with.

There is a striking analogy between the letters of our alphabet and their relation to the language of the vast volume of printed books, and the eighty or more primary elements and their relation to the vast universe of material things. The analogy may not be in all respects a strictly true one, but it is an illuminating one. Our twenty-six letters combined and repeated in different orders give us the many thousand words our language possesses, and these words combined and repeated in different orders give us the vast body of printed books in our libraries. The ultimate parts—the atoms and molecules of all literature, so to speak—are the letters of the alphabet. How often by changing a letter in a word, by reversing their order, or by substituting one letter for another, we get a word of an entirely different meaning, as in umpire and empire, petrifaction and putrefaction, malt and salt, tool and fool. And by changing the order of the words in a sentence we express all the infinite variety of ideas and meanings that the books of the world hold.

The eighty or more primordial elements are Nature's alphabet with which she writes her "infinite book of secrecy." Science shows pretty conclusively that the character of the different substances, their diverse qualities and properties, depend upon the order in which the atoms and molecules are combined. Change the order in which the molecules of the carbon and oxygen are combined in alcohol, and we get ether—the chemical formula remaining the same. Or take ordinary spirits of wine and add four more atoms of carbon to the carbon molecules, and we have the poison, carbolic acid. Pure alcohol is turned into a deadly poison by taking from it one atom of carbon and two of hydrogen. With the atoms of carbon, hydrogen, and oxygen, by combining them in different proportions and in different orders, Nature produces such diverse bodies as acetic acid, alcohol, sugar, starch, animal fats, vegetable oils, glycerine, and the like. So with the long list of hydrocarbons—gaseous, liquid, and solid—called paraffins, that are obtained from petroleum and that are all composed of hydrogen and carbon, but with a different number of atoms of each, like a different number of a's or b's or c's in a word.

What an enormous number of bodies Nature forms out of oxygen by uniting it chemically with other primary elements! Thus by uniting it with the element silica she forms half of the solid crust of the globe; by uniting it with hydrogen in the proportion of two to one she forms all the water of the globe. With one atom of nitrogen united chemically with three atoms of hydrogen she forms ammonia. With one atom of carbon united with four atoms of hydrogen she spells marsh gas; and so on. Carbon occurs in inorganic nature in two crystalline forms,—the diamond and black lead, or graphite,—their physical differences evidently being the result of their different molecular structure. Graphite is a good conductor of heat and electricity, and the diamond is not. Carbon in the organic world, where it plays such an important part, is non-crystalline. Under the influence of life its molecules are differently put together, as in sugar, starch, wood, charcoal, etc. There are also two forms of phosphorus, but not two kinds; the same atoms are probably united differently in each. The yellow waxy variety has such an affinity for oxygen that it will burn in water, and it is poisonous. Bring this variety to a high temperature away from the air, and its molecular structure seems to change, and we have the red variety, which is tasteless, odorless, and non-poisonous, and is not affected by contact with the air. Such is the mystery of chemical change.

IV

Science has developed methods and implements of incredible delicacy. Its "microbalance" can estimate "the difference of weight of the order of the millionth of a milligram." Light travels at the speed of 186,000 miles a second, yet science can follow it with its methods, and finds that it travels faster with the current of running water than against it. Science has perfected a thermal instrument by which it can detect the heat of a lighted candle six miles away, and the warmth of the human face several miles distant. It has devised a method by which it can count the particles in the alpha rays of radium that move at a velocity of twenty thousand kilometers a second, and a method by which, through the use of a screen of zinc-sulphide, it can see the flashes produced by the alpha atoms when they strike this screen. It weighs and counts and calculates the motions of particles of matter so infinitely small that only the imagination can grasp them. Its theories require it to treat the ultimate particles into which it resolves matter, and which are so small that they are no longer divisible, as if they were solid bodies with weight and form, with centre and circumference, colliding with one another like billiard-balls, or like cosmic bodies in the depths of space, striking one another squarely, and, for aught I know, each going through another, or else grazing one another and glancing off. To particles of matter so small that they can no longer be divided or made smaller, the impossible feat of each going through the centre of another, or of each enveloping the other, might be affirmed of them without adding to their unthinkableness. The theory is that if we divide a molecule of water the parts are no longer water, but atoms of hydrogen and oxygen—real bodies with weight and form, and storehouses of energy, but no longer divisible.

Indeed, the atomic theory of matter leads us into a non-material world, or a world the inverse of the solid, three-dimensioned world that our senses reveal to us, or to matter in a fourth estate. We know solids and fluids and gases; but emanations which are neither we know only as we know spirits and ghosts—by dreams or hearsay. Yet this fourth or ethereal estate of matter seems to be the final, real, and fundamental condition.

How it differs from spirit is not easy to define. The beta ray of radium will penetrate solid iron a foot thick, a feat that would give a spirit pause. The ether of space, which science is coming more and more to look upon as the mother-stuff of all things, has many of the attributes of Deity. It is omni-present and all-powerful. Neither time nor space has dominion over it. It is the one immutable and immeasurable thing in the universe. From it all things arise and to it they return. It is everywhere and nowhere. It has none of the finite properties of matter—neither parts, form, nor dimension; neither density nor tenuity; it cannot be compressed nor expanded nor moved; it has no inertia nor mass, and offers no resistance; it is subject to no mechanical laws, and no instrument or experiment that science has yet devised can detect its presence; it has neither centre nor circumference, neither extension nor boundary. And yet science is as convinced of its existence as of the solid ground beneath our feet. It is the one final reality in the universe, if we may not say that it is the universe. Tremors or vibrations in it reach the eye and make an impression that we call light; electrical oscillations in it are the source of other phenomena. It is the fountain-head of all potential energy. The ether is an invention of the scientific imagination. We had to have it to account for light, gravity, and the action of one body upon another at a distance, as well as to account for other phenomena. The ether is not a body, it is a medium. All bodies are in motion; matter moves; the ether is in a state of absolute rest. Says Sir Oliver Lodge, "The ether is strained, and has the property of exerting strain and recoil." An electron is like a knot in the ether. The ether is the fluid of fluids, yet its tension or strain is so great that it is immeasurably more dense than anything else—a phenomenon that may be paralleled by a jet of water at such speed that it cannot be cut with a sword or severed by a hammer. It is so subtle or imponderable that solid bodies are as vacuums to it, and so pervasive that all conceivable space is filled with it; "so full," says Clerk Maxwell, "that no human power can remove it from the smallest portion of space, or produce the slightest flaw in its infinite continuity."

The scientific imagination, in its attempts to master the workings of the material universe, has thus given us a creation which in many of its attributes rivals Omnipotence. It is the sum of all contradictions, and the source of all reality. The gross matter which we see and feel is one state of it; electricity, which is without form and void, is another state of it; and our minds and souls, Sir Oliver Lodge intimates, may be still another state of it. But all these theories of physical science are justified by their fruits. The atomic theory of matter, and the kinetic theory of gases, are mathematically demonstrated. However unreal and fantastic they may appear to our practical faculties, conversant only with ponderable bodies, they bear the test of the most rigid and exact experimentation.

V

After we have marveled over all these hidden things, and been impressed by the world within world of the material universe, do we get any nearer to the mystery of life? Can we see where the tremendous change from the non-living to the living takes place? Can we evoke life from the omnipotent ether, or see it arise in the whirling stream of atoms and electrons? Molecular science opens up to us a world where the infinitely little matches the infinitely great, where matter is dematerialized and answers to many of the conceptions of spirit; but does it bring us any nearer the origin of life? Is radio-active matter any nearer living matter than is the clod under foot? Are the darting electrons any more vital than the shooting-stars? Can a flash of radium emanations on a zinc-sulphide plate kindle the precious spark? It is probably just as possible to evoke vitality out of the clash of billiard-balls as out of the clash of atoms and electrons. This allusion to billiard-balls recalls to my mind a striking passage from Tyndall's famous Belfast Address which he puts in the mouth of Bishop Butler in his imaginary argument with Lucretius, and which shows how thoroughly Tyndall appreciated the difficulties of his own position in advocating the theory of the physico-chemical origin of life.

The atomic and electronic theory of matter admits one to a world that does indeed seem unreal and fantastic. "If my bark sinks," says the poet, "'t is to another sea." If the mind breaks through what we call gross matter, and explores its interior, it finds itself indeed in a vast under or hidden world—a world almost as much a creation of the imagination as that visited by Alice in Wonderland, except that the existence of this world is capable of demonstration. It is a world of the infinitely little which science interprets in terms of the infinitely large. Sir Oliver Lodge sees the molecular spaces that separate the particles of any material body relatively like the interstellar spaces that separate the heavenly bodies. Just as all the so-called solid matter revealed by our astronomy is almost infinitesimal compared with the space through which it is distributed, so the electrons which compose the matter with which we deal are comparable to the bodies of the solar system moving in vast spaces. It is indeed a fantastic world where science conceives of bodies a thousand times smaller than the hydrogen atom—the smallest body known to science; where it conceives of vibrations in the ether millions of millions times a second; where we are bombarded by a shower of corpuscles from a burning candle, or a gas-jet, or a red-hot iron surface, moving at the speed of one hundred thousand miles a second! But this almost omnipotent ether has, after all, some of the limitations of the finite. It takes time to transmit the waves of light from the sun and the stars. This measurable speed, says Sir Oliver Lodge, gives the ether away, and shows its finite character.

It seems as if the theory of the ether must be true, because it fits in so well with the enigmatic, contradictory, incomprehensible character of the universe as revealed to our minds. We can affirm and deny almost anything of the ether—that it is immaterial, and yet the source of all material; that it is absolutely motionless, yet the cause of all motion; that it is the densest body in nature, and yet the most rarified; that it is everywhere, but defies detection; that it is as undiscoverable as the Infinite itself; that our physics cannot prove it, though they cannot get along without it. The ether inside a mass of iron or of lead is just as dense as the ether outside of it—which means that it is not dense at all, in our ordinary use of the term.

VI

There are physical changes in matter, there are chemical changes, and there is a third change, as unlike either of these as they are unlike each other. I refer to atomic change, as in radio-activity, which gives us lead from helium—a spontaneous change of the atoms. The energy that keeps the earth going, says Soddy, is to be sought for in the individual atoms; not in the great heaven-shaking voice of thunder, but in the still small voice of the atoms. Radio-activity is the mainspring of the universe. The only elements so far known that undergo spontaneous change are uranium and thorium. One pound of uranium contains and slowly gives out the same amount of energy that a hundred tons of coal evolves in its combustion, but only one ten-billionth part of this amount is given out every year.

Man, of course, reaps where he has not sown. How could it be otherwise? It takes energy to sow or plant energy. We are exhausting the coal, the natural gas, the petroleum of the rocks, the fertility of the soil. But we cannot exhaust the energy of the winds or the tides, or of falling water, because this energy is ever renewed by gravity and the sun. There can be no exhaustion of our natural mechanical and chemical resources, as some seem to fear.

I recently visited a noted waterfall in the South where electric power is being developed on a large scale. A great column of water makes a vertical fall of six hundred feet through a steel tube, and in the fall develops two hundred and fifty thousand horse-power. The water comes out of the tunnel at the bottom, precisely the same water that went in at the top; no change whatever has occurred in it, yet a vast amount of power has been taken out of it, or, rather, generated by its fall. Another drop of six hundred feet would develop as much more; in fact, the process may be repeated indefinitely, the same amount of power resulting each time, without effecting any change in the character of the water. The pull of gravity is the source of the power which is distributed hundreds of miles across the country as electricity. Two hundred and fifty thousand invisible, immaterial, noiseless horses are streaming along these wires with incredible speed to do the work of men and horses in widely separated parts of the country. A river of sand falling down those tubes, if its particles moved among themselves with the same freedom that those of the water do, would develop the same power. The attraction of gravitation is not supposed to be electricity, and yet here out of its pull upon the water comes this enormous voltage! The fact that such a mysterious and ubiquitous power as electricity can be developed from the action of matter without any alteration in its particles, suggests the question whether or not this something that we call life, or life-force, may not slumber in matter in the same way; but the secret of its development we have not yet learned, as we have that of electricity.

Radio-activity is uninfluenced by external conditions; hence we are thus far unable to control it. Nothing that is known will effect the transmutation of one element into another. It is spontaneous and uncontrollable. May not life be spontaneous in the same sense?

The release of the energy associated with the structure of the atoms is not available by any of our mechanical appliances. The process of radio-activity involves the expulsion of atoms of helium with a velocity three hundred times greater than that ever previously known for any material mass or particle, and this power we are incompetent to use. The atoms remain unchanged amid the heat and pressure of the laboratory of nature. Iron and oxygen and so forth remain the same in the sun as here on the earth.

Science strips gross matter of its grossness. When it is done with it, it is no longer the obstructive something we know and handle; it is reduced to pure energy—the line between it and spirit does not exist. We have found that bodies are opaque only to certain rays; the X-ray sees through this too too solid flesh. Bodies are ponderable only to our dull senses; to a finer hand than this the door or the wall might offer no obstruction; a finer eye than this might see the emanations from the living body; a finer ear might hear the clash of electrons in the air. Who can doubt, in view of what we already know, that forces and influences from out the heavens above, and from the earth beneath, that are beyond our ken, play upon us constantly?

The final mystery of life is no doubt involved in conditions and forces that are quite outside of or beyond our conscious life activities, in forces that play about us and upon and through us, that we know not of, because a knowledge of them is not necessary to our well-being. "Our eye takes in only an octave of the vibrations we call light," because no more is necessary for our action or our dealing with things. The invisible rays of the spectrum are potent, but they are beyond the ken of our senses. There are sounds or sound vibrations that we do not hear; our sense of touch cannot recognize a gossamer, or the gentler air movements.

I began with the contemplation of the beauty and terror of the thunderbolt—"God's autograph," as one of our poets (Joel Benton) said, "written upon the sky." Let me end with an allusion to another aspect of the storm that has no terror in it—the bow in the clouds: a sudden apparition, a cosmic phenomenon no less wonderful and startling than the lightning's flash. The storm with terror and threatened destruction on one side of it, and peace and promise on the other! The bow appears like a miracle, but it is a commonplace of nature; unstable as life, and beautiful as youth. The raindrops are not changed, the light is not changed, the laws of the storms are not changed; and yet, behold this wonder!

But all these strange and beautiful phenomena springing up in a world of inert matter are but faint symbols of the mystery and the miracle of the change of matter from the non-living to the living, from the elements in the clod to the same elements in the brain and heart of man.

IV

THE BAFFLING PROBLEM

I

Still the problem of living things haunts my mind and, let me warn my reader, will continue to haunt it throughout the greater part of this volume. The final truth about it refuses to be spoken. Every effort to do so but gives one new evidence of how insoluble the problem is.

In this world of change is there any other change to be compared with that in matter, from the dead to the living?—a change so great that most minds feel compelled to go outside of matter and invoke some super-material force or agent to account for it. The least of living things is so wonderful, the phenomena it exhibits are so fundamentally unlike those of inert matter, that we invent a word for it, vitality; and having got the word, we conceive of a vital force or principle to explain vital phenomena. Hence vitalism—a philosophy of living things, more or less current in the world from Aristotle's time down to our own. It conceives of something in nature super-mechanical and super-chemical, though inseparably bound up with these things. There is no life without material and chemical forces, but material and chemical forces do not hold the secret of life. This is vitalism as opposed to mechanism, or scientific materialism, which is the doctrine of the all-sufficiency of the physical forces operating in the inorganic world to give rise to all the phenomena of the organic world—a doctrine coming more and more in vogue with the progress of physical science. Without holding to any belief in the supernatural or the teleological, and while adhering to the idea that there has been, and can be, no break in the causal sequence in this world, may one still hold to some form of vitalism, and see in life something more than applied physics and chemistry?

Is biology to be interpreted in the same physical and chemical terms as geology? Are biophysics and geophysics one and the same? One may freely admit that there cannot be two kinds of physics, nor two kinds of chemistry—not one kind for a rock, and another kind for a tree, or a man. There are not two species of oxygen, nor two of carbon, nor two of hydrogen and nitrogen—one for living and one for dead matter. The water in the human body is precisely the same as the water that flows by in the creek or that comes down when it rains; and the sulphur and the lime and the iron and the phosphorus and the magnesium are identical, so far as chemical analysis can reveal, in the organic and the inorganic worlds. But are we not compelled to think of a kind of difference between a living and a non-living body that we cannot fit into any of the mechanical or chemical concepts that we apply to the latter? Professor Loeb, with his "Mechanistic Conception of Life"; Professor Henderson, of Harvard, with his "Fitness of the Environment"; Professor Le Dantec, of the Sorbonne in Paris, with his volume on "The Nature and Origin of Life," published a few years since; Professor Schäfer, President of the British Association, Professor Verworn of Bonn, and many others find in the laws and properties of matter itself a sufficient explanation of all the phenomena of life. They look upon the living body as only the sum of its physical and chemical activities; they do not seem to feel the need of accounting for life itself—for that something which confers vitality upon the heretofore non-vital elements. That there is new behavior, that there are new chemical compounds called organic,—tens of thousands of them not found in inorganic nature,—that there are new processes set up in aggregates of matter,—growth, assimilation, metabolism, reproduction, thought, emotion, science, civilization,—no one denies.

How are we going to get these things out of the old physics and chemistry without some new factor or agent or force? To help ourselves out here with a "vital principle," or with spirit, or a creative impulse, as Bergson does, seems to be the only course open to certain types of mind. Positive science cannot follow us in this step, because science is limited to the verifiable. The stream of forces with which it deals is continuous; it must find the physical equivalents of all the forces that go into the body in the output of the body, and it cannot admit of a life force which it cannot trace to the physical forces.

What has science done to clear up this mystery of vitality? Professor Loeb, our most eminent experimental biologist, has succeeded in fertilizing the eggs of some low forms of sea life by artificial means; and in one instance, at least, it is reported that the fatherless form grew to maturity. This is certainly an interesting fact, but takes us no nearer the solution of the mystery of vitality than the fact that certain chemical compounds may stimulate the organs of reproduction helps to clear up the mystery of generation; or the fact that certain other chemical compounds help the digestive and assimilative processes and further the metabolism of the body assists in clearing up the mystery that attaches to these things. In all such cases we have the living body to begin with. The egg of the sea-urchin and the egg of the jelly-fish are living beings that responded to certain chemical substances, so that a process is set going in their cell life that is equivalent to fertilization. It seems to me that the result of all Professor Loeb's valuable inquiries is only to give us a more intimate sense of how closely mechanical and chemical principles are associated and identified with all the phenomena of life and with all animal behavior. Given a living organism, mechanics and chemistry will then explain much of its behavior—practically all the behavior of the lower organisms, and much of that of the higher. Even when we reach man, our reactions to the environment and to circumstances play a great part in our lives; but dare we say that will, liberty of choice, ideation, do not play a part also? How much reality there is in the so-called animal will, is a problem; but that there is a foundation for our belief in the reality of the human will, I, for one, do not for a moment doubt. The discontinuity here is only apparent and not real. We meet with the same break when we try to get our mental states, our power of thought—a poem, a drama, a work of art, a great oration—out of the food we eat; but life does it, though our science is none the wiser for it. Our physical life forms a closed circle, science says, and what goes into our bodies as physical force, must come out in physical force, or as some of its equivalents. Well, one of the equivalents, transformed by some unknown chemism within us, is our psychic force, or states of consciousness. The two circles, the physical and the psychical, are not concentric, as Fiske fancied, but are linked in some mysterious way.

Professor Loeb is a master critic of the life processes; he and his compeers analyze them as they have never been analyzed before; but the solution of the great problem of life that we are awaiting does not come. A critic may resolve all of Shakespeare's plays into their historic and other elements, but that will not account for Shakespeare. Nature's synthesis furnishes occasions for our analysis. Most assuredly all psychic phenomena have a physical basis; we know the soul only through the body; but that they are all of physico-chemical origin, is another matter.

II

Biological science has hunted the secret of vitality like a detective; and it has done some famous work; but it has not yet unraveled the mystery. It knows well the part played by carbon, oxygen, and hydrogen in organic chemistry, that without water and carbon dioxide there could be no life; it knows the part played by light, air, heat, gravity, osmosis, chemical affinity, and all the hundreds or thousands of organic compounds; it knows the part played by what are called the enzymes, or ferments, in all living bodies, but it does not know the secret of these ferments; it knows the part played by colloids, or jelly-like compounds, that there is no living body without colloids, though there are colloid bodies that are not living; it knows the part played by oxidation, that without it a living body ceases to function, though everywhere all about us is oxidation without life; it knows the part played by chlorophyll in the vegetable kingdom, and yet how chlorophyll works such magic upon the sun's rays, using the solar energy to fix the carbon of carbonic acid in the air, and thereby storing this energy as it is stored in wood and coal and in much of the food we consume, is a mystery. Chemistry cannot repeat the process in its laboratories. The fungi do not possess this wonderful chlorophyllian power, and hence cannot use the sunbeam to snatch their carbon from the air; they must get it from decomposed vegetable matter; they feed, as the animals do, upon elements that have gone through the cycle of vegetable life. The secret of vegetable life, then, is in the green substance of the leaf where science is powerless to unlock it. Conjure with the elements as it may, it cannot produce the least speck of living matter. It can by synthesis produce many of the organic compounds, but only from matter that has already been through the organic cycle. It has lately produced rubber, but from other products of vegetable life.

As soon as the four principal elements, carbon, oxygen, hydrogen, and nitrogen, that make up the living body, have entered the world of living matter, their activities and possible combinations enormously increase; they enter into new relations with one another and form compounds of great variety and complexity, characterized by the instability which life requires. The organic compounds are vastly more sensitive to light and heat and air than are the same elements in the inorganic world. What has happened to them? Chemistry cannot tell us. Oxidation, which is only slow combustion, is the main source of energy in the body, as it is in the steam-engine. The storing of the solar energy, which occurs only in the vegetable, is by a process of reduction, that is, the separation of the carbon and oxygen in carbonic acid and water. The chemical reactions which liberate energy in the body are slow; in dead matter they are rapid and violent, or explosive and destructive. It is the chemistry in the leaf of the plant that diverts or draws the solar energy into the stream of life, and how it does it is a mystery.

The scientific explanations of life phenomena are all after the fact; they do not account for the fact; they start with the ready-made organism and then reduce its activities and processes to their physical equivalents. Vitality is given, and then the vital processes are fitted into mechanical and chemical concepts, or into moulds derived from inert matter—not a difficult thing to do, but no more an explanation of the mystery of vitality than a painting or a marble bust of Tyndall would be an explanation of that great scientist.

All Professor Loeb's experiments and criticisms throw light upon the life processes, or upon the factors that take part in them, but not upon the secret of the genesis of the processes themselves. Amid all the activities of his mechanical and chemical factors, there is ever present a factor which he ignores, which his analytical method cannot seize; namely, what Verworn calls "the specific energy of living substance." Without this, chemism and mechanism would work together to quite other ends. The water in the wave, and the laws that govern it, do not differ at all from the water and its laws that surround it; but unless one takes into account the force that makes the wave, an analysis of the phenomena will leave one where he began.

Professor Le Dantec leaves the subject where he took it up, with the origin of life and the life processes unaccounted for. His work is a description, and not an explanation. All our ideas about vitality, or an unknown factor in the organic world, he calls "mystic" and unscientific. A sharp line of demarcation between living and non-living bodies is not permissible. This, he says, is the anthropomorphic error which puts some mysterious quality or force in all bodies considered to be living. To Le Dantec, the difference between the quick and the dead is of the same order as the difference which exists between two chemical compounds—for example, as that which exists between alcohol and an aldehyde, a liquid that has two less atoms of hydrogen in its composition. Modify your chemistry a little, add or subtract an atom or two, more or less, of this or that gas, and dead matter thrills into life, or living matter sinks to the inert. In other words, life is the gift of chemistry, its particular essence is of the chemical order—a bold inference from the fact that there is no life without chemical reactions, no life without oxidation. Yet chemical reactions in the laboratory cannot produce life. With Le Dantec, biology, like geology and astronomy, is only applied mechanics and chemistry.

III

Such is the result of the rigidly objective study of life—the only method analytical science can pursue. The conception of vitality as a factor in itself answers to nothing that the objective study of life can disclose; such a study reveals a closed circle of physical forces, chemical and mechanical, into which no immaterial force or principle can find entrance. "The fact of being conscious," Le Dantec says with emphasis, "does not intervene in the slightest degree in directing vital movements." But common sense and everyday observation tell us that states of consciousness do influence the bodily processes—influence the circulation, the digestion, the secretions, the respiration.

An objective scientific study of a living body yields results not unlike those which we might get from an objective study of a book considered as something fabricated—its materials, its construction, its typography, its binding, the number of its chapters and pages, and so on—without giving any heed to the meaning of the book—its ideas, the human soul and personality that it embodies, the occasion that gave rise to it, indeed all its subjective and immaterial aspects. All these things, the whole significance of the volume, would elude scientific analysis. It would seem to be a manufactured article, representing only so much mechanics and chemistry. It is the same with the living body. Unless we permit ourselves to go behind the mere facts, the mere mechanics and chemistry of life phenomena, and interpret them in the light of immaterial principles, in short, unless we apply some sort of philosophy to them, the result of our analysis will be but dust in our eyes, and ashes in our mouths. Unless there is something like mind or intelligence pervading nature, some creative and transforming impulse that cannot be defined by our mechanical concepts, then, to me, the whole organic world is meaningless. If man is not more than an "accident in the history of the thermic evolution of the globe," or the result of the fortuitous juxtaposition and combination of carbonic acid gas and water and a few other elements, what shall we say? It is at least a bewildering proposition.

Could one by analyzing a hive of bees find out the secret of its organization—its unity as an aggregate of living insects? Behold its wonderful economics, its division of labor, its complex social structure,—the queen, the workers, the drones,—thousands of bees without any head or code of laws or directing agent, all acting as one individual, all living and working for the common good. There is no confusion or cross-purpose in the hive. When the time of swarming comes, they are all of one mind and the swarm comes forth. Who or what decides who shall stay and who shall go? When the honey supply fails, or if it fail prematurely, on account of a drought, the swarming instinct is inhibited, and the unhatched queens are killed in their cells. Who or what issues the regicide order? We can do no better than to call it the Spirit of the Hive, as Maeterlinck has done. It is a community of mind. What one bee knows and feels, they all know and feel at the same instant. Something like that is true of a living body; the cells are like the bees: they work together, they build up the tissues and organs, some are for one thing and some for another, each community of cells plays its own part, and they all pull together for the good of the whole. We can introduce cells and even whole organs, for example a kidney from another living body, and all goes well; and yet we cannot find the seat of the organization. Can we do any better than to call it the Spirit of the Body?

IV

Our French biologist is of the opinion that the artificial production of that marvel of marvels, the living cell, will yet take place in the laboratory. But the enlightened mind, he says, does not need such proof to be convinced that there is no essential difference between living and non-living matter.

Professor Henderson, though an expounder of the mechanistic theory of the origin of life, admits that he does not know of a biological chemist to whom the "mechanistic origin of a cell is scientifically imaginable." Like Professor Loeb, he starts with the vital; how he came by it we get no inkling; he confesses frankly that the biological chemist cannot even face the problem of the origin of life. He quotes with approval a remark of Liebig's, as reported by Lord Kelvin, that he (Liebig) could no more believe that a leaf or a flower could be formed or could grow by chemical forces "than a book on chemistry, or on botany, could grow out of dead matter." Is not this conceding to the vitalists all that they claim? The cell is the unit of life; all living bodies are but vast confraternities of cells, some billions or trillions of them in the human body; the cell builds up the tissues, the tissues build up the organs, the organs build up the body. Now if it is not thinkable that chemism could beget a cell, is it any more thinkable that it could build a living tissue, and then an organ, and then the body as a whole? If there is an inscrutable something at work at the start, which organizes that wonderful piece of vital mechanism, the cell, is it any the less operative ever after, in all life processes, in all living bodies and their functions,—the vital as distinguished from the mechanical and chemical? Given the cell, and you have only to multiply it, and organize these products into industrial communities, and direct them to specific ends,—certainly a task which we would not assign to chemistry or physics any more than we would assign to them the production of a work on chemistry or botany,—and you have all the myriad forms of terrestrial life.

The cell is the parent of every living thing on the globe; and if it is unthinkable that the material and irrational forces of inert matter could produce it, then mechanics and chemistry must play second fiddle in all that whirl and dance of the atoms that make up life. And that is all the vitalists claim. The physico-chemical forces do play second fiddle; that inexplicable something that we call vitality dominates and leads them. True it is that a living organism yields to scientific analysis only mechanical and chemical forces—a fact which only limits the range of scientific analysis, and which by no means exhausts the possibilities of the living organism. The properties of matter and the laws of matter are intimately related to life, yea, are inseparable from it, but they are by no means the whole story. Professor Henderson repudiates the idea of any extra-physical influence as being involved in the processes of life, and yet concedes that the very foundation of all living matter, yea, the whole living universe in embryo—the cell—is beyond the possibilities of physics and chemistry alone. Mechanism and chemism are adequate to account for astronomy and geology, and therefore, he thinks, are sufficient to account for biology, without calling in the aid of any Bergsonian life impulse. Still these forces stand impotent before that microscopic world, the cell, the foundation of all life.

Our professor makes the provisional statement, not in obedience to his science, but in obedience to his philosophy, that something more than mechanics and chemistry may have had a hand in shaping the universe, some primordial tendency impressed upon or working in matter "just before mechanism begins to act"—"a necessary and preëstablished associate of mechanism." So that if we start with the universe, with life, and with this tendency, mechanism will do all the rest. But this is not science, of course, because it is not verifiable; it is practically the philosophy of Bergson.

The cast-iron conclusions of physical science do pinch the Harvard professor a bit, and he pads them with a little of the Bergsonian philosophy. Bergson himself is not pinched at all by the conclusions of positive science. He sees that we, as human beings, cannot live in this universe without supplementing our science with some sort of philosophy that will help us to escape from the fatalism of matter and force into the freedom of the spiritual life. If we are merely mechanical and chemical accidents, all the glory of life, all the meaning of our moral and spiritual natures, go by the board.

Professor Henderson shows us how well this planet, with its oceans and continents, and its mechanical and chemical forces and elements, is suited to sustain life, but he brings us no nearer the solution of the mystery than we were before. His title, to begin with, is rather bewildering. Has the "fitness of the environment" ever been questioned? The environment is fit, of course, else living bodies would not be here. We are used to taking hold of the other end of the problem. In living nature the foot is made to fit the shoe, and not the shoe the foot. The environment is the mould in which the living organism is cast. Hence, it seems to me, that seeking to prove the fitness of the environment is very much like seeking to prove the fitness of water for fish to swim in, or the fitness of the air for birds to fly in. The implication seems to be made that the environment anticipates the organism, or meets it half way. But the environment is rather uncompromising. Man alone modifies his environment by the weapon of science; but not radically; in the end he has to fit himself to it. Life has been able to adjust itself to the universal forces and so go along with them; otherwise we should not be here. We may say, humanly speaking, that the water is friendly to the swimmer, if he knows how to use it; if not, it is his deadly enemy. The same is true of all the elements and forces of nature. Whether they be for or against us, depends upon ourselves. The wind is never tempered to the shorn lamb, the shorn lamb must clothe itself against the wind. Life is adaptive, and this faculty of adaptation to the environment, of itself takes it out of the category of the physico-chemical. The rivers and seas favor navigation, if we have gumption enough to use and master their forces. The air is good to breathe, and food to eat, for those creatures that are adapted to them. Bergson thinks, not without reason, that life on other planets may be quite different from what it is on our own, owing to a difference in chemical and physical conditions. Change the chemical constituents of sea water, and you radically change the lower organisms. With an atmosphere entirely of oxygen, the processes of life would go on more rapidly and perhaps reach a higher form of development. Life on this planet is limited to a certain rather narrow range of temperature; the span may be the same in other worlds, but farther up or farther down the scale. Had the air been differently constituted, would not our lungs have been different? The lungs of the fish are in his gills: he has to filter his air from a much heavier medium. The nose of the pig is fitted for rooting; shall we say, then, that the soil was made friable that pigs might root in it? The webbed foot is fitted to the water; shall we say, then, that water is liquid in order that geese and ducks may swim in it? One more atom of oxygen united to the two atoms that go to make the molecule of air, and we should have had ozone instead of the air we now breathe. How unsuited this would have made the air for life as we know it! Oxidation would have consumed us rapidly. Life would have met this extra atom by some new device.

One wishes Professor Henderson had told us more about how life fits itself to the environment—how matter, moved and moulded only by mechanical and chemical forces, yet has some power of choice that a machine does not have, and can and does select the environment best suited to its well-being. In fact, that it should have, or be capable of, any condition of well-being, if it is only a complex of physical and chemical forces, is a problem to wrestle with. The ground we walk on is such a complex, but only the living bodies it supports have conditions of well-being.

Professor Henderson concedes very little to the vitalists or the teleologists. He is a thorough mechanist. "Matter and energy," he says, "have an original property, assuredly not by chance, which organizes the universe in space and time." Where or how matter got this organizing property, he offers no opinion. "Given the universe, life, and the tendency [the tendency to organize], mechanism is inductively proved sufficient to account for all phenomena." Biology, then, is only mechanics and chemistry engaged in a new rôle without any change of character; but what put them up to this new rôle? "The whole evolutionary process, both cosmic and organic, is one, and the biologist may now rightly regard the universe in its very essence as biocentric."

V

Another Harvard voice is less pronounced in favor of the mechanistic conception of life. Professor Rand thinks that in a mechanically determined universe, "our conscious life becomes a meaningless replica of an inexorable physical concatenation"—the soul the result of a fortuitous concourse of atoms. Hence all the science and art and literature and religion of the world are merely the result of a molecular accident.

Dr. Rand himself, in wrestling with the problem of organization in a late number of "Science," seems to hesitate whether or not to regard man as a molecular accident, an appearance presented to us by the results of the curious accidents of molecules—which is essentially Professor Loeb's view; or whether to look upon the living body as the result of a "specific something" that organizes, that is, of "dominating organic agencies," be they psychic or super-mundane, which dominate and determine the organization of the different parts of the body into a whole. Yet he is troubled with the idea that this specific something may be "nothing more than accidental chemical peculiarities of cells." But would these accidental peculiarities be constant? Do accidents happen millions of times in the same way? The cell is without variableness or shadow of turning. The cells are the minute people that build up all living forms, and what prompts them to build a man in the one case, and the man's dog in another, is the mystery that puzzles Professor Rand. "Tissue cells," he says, "are not structures like stone blocks laboriously carved and immovably cemented in place. They are rather like the local eddies in an ever-flowing and ever-changing stream of fluids. Substance which was at one moment a part of a cell, passes out and a new substance enters. What is it that prevents the local whirl in this unstable stream from changing its form? How is it that a million muscle cells remain alike, collectively ready to respond to a nerve impulse?" According to one view, expressed by Professor Rand, "Organization is something that we read into natural phenomena. It is in itself nothing." The alternative view holds that there is a specific organizing agent that brings about the harmonious operation of all the organs and parts of the system—a superior dynamic force controlling and guiding all the individual parts.

A most determined and thorough-going attempt to hunt down the secret of vitality, and to determine how far its phenomena can be interpreted in terms of mechanics and chemistry, is to be found in Professor H. W. Conn's volume entitled "The Living Machine." Professor Conn justifies his title by defining a machine as "a piece of apparatus so designed that it can change one kind of energy into another for a definite purpose." Of course the adjective "living" takes it out of the category of all mere mechanical devices and makes it super-mechanical, just as Haeckel's application of the word "living" to his inorganics ("living inorganics"), takes them out of the category of the inorganic. In every machine, properly so called, all the factors are known; but do we know all the factors in a living body? Professor Conn applies his searching analysis to most of the functions of the human body, to digestion, to assimilation, to circulation, to respiration, to metabolism, and so on, and he finds in every function something that does not fall within his category—some force not mechanical nor chemical, which he names vital.

In following the processes of digestion, all goes well with his chemistry and his mechanics till he comes to the absorption of food-particles, or their passage through the walls of the intestines into the blood. Here, the ordinary physical forces fail him, and living matter comes to his aid. The inner wall of the intestine is not a lifeless membrane, and osmosis will not solve the mystery. There is something there that seizes hold of the droplets of oil by means of little extruded processes, and then passes them through its own body to excrete them on an inner surface into the blood-vessels. "This fat absorption thus appears to be a vital process and not one simply controlled by physical forces like osmosis. Here our explanation runs against what we call 'vital power' of the ultimate elements of the body." Professor Conn next analyzes the processes of circulation, and his ready-made mechanical concepts carry him along swimmingly, till he tries to explain by them the beating of the heart, and the contraction of the small blood-vessels which regulate the blood-supply. Here comes in play the mysterious vital power again. He comes upon the same power when he tries to determine what it is that enables the muscle-fibre to take from the lymph the material needed for its use, and to discard the rest. The fibre acts as if it knew what it wanted—a very unmechanical attribute.

Then Professor Conn applies his mechanics and chemistry to the respiratory process and, of course, makes out a very clear case till he comes to the removal of the waste, or ash. The steam-engine cannot remove its own ash; the "living machine" can. Much of this ash takes the form of urea, and "the seizing upon the urea by the kidney cells is a vital phenomenon." Is not the peristaltic movement of the bowels, by which the solid matter is removed, also a vital phenomenon? Is not the conception of a pipe or a tube that forces semi-fluid matter along its hollow interior, by the contraction of its walls, quite beyond the reach of mechanics? The force is as mechanical as the squeezing of the bulb of a syringe by the hand, but in the case of the intestines, what does the squeezing? The vital force?

When the mechanical and chemical concepts are applied to the phenomena of the nervous system, they work very well till we come to mental phenomena. When we try to correlate physical energy with thought or consciousness, we are at the end of our tether. Here is a gulf we cannot span. The theory of the machine breaks down. Some other force than material force is demanded here, namely, psychical,—a force or principle quite beyond the sphere of the analytic method.

Hence Professor Conn concludes that there are vital factors and that they are the primal factors in the organism. The mechanical and chemical forces are the secondary factors. It is the primal factors that elude scientific analysis. Why a muscle contracts, or why a gland secretes, or "why the oxidation of starch in the living machine gives rise to motion, growth, and reproduction, while if the oxidation occurs in the chemist's laboratory ... it simply gives rise to heat," are questions he cannot answer. In all his inquiries into the parts played by mechanical and chemical laws in the organism, he is compelled to "assume as their foundation the simple vital properties of living phenomena."

VI

It should not surprise nor disturb us that the scientific interpretation of life leads to materialism, or to the conviction of the all-sufficiency of the mechanical and chemical forces of dead matter to account for all living phenomena. It need not surprise us because positive science, as such, can deal only with physical and chemical forces. If there is anything in this universe besides physical and chemical force, science does not know it. It does not know it because it is absolutely beyond the reach of its analysis. When we go beyond the sphere of the concrete, the experimental, the verifiable, only our philosophy can help us. The world within us, the world of psychic forces, is beyond the ken of science. It can analyze the living body, trace all its vital processes, resolve them into their mechanical and chemical equivalents, show us the parts played by the primary elements, the part played by the enzymes, or ferments, and the like, and yet it cannot tell us the secret of life—of that which makes organic chemistry so vastly different from inorganic. It discloses to us the wonders of the cell—a world of mystery by itself; it analyzes the animal body into organs, and the organs into tissues, and the tissues into cells, but the secret of organization utterly baffles it. After Professor Wilson had concluded his masterly work on the cell, he was forced to admit that the final mystery of the cell eluded him, and that his investigation "on the whole seemed to widen rather than to narrow the enormous gap that separates even the lowest forms of life from the inorganic world."

All there is outside the sphere of physical science belongs to religion, to philosophy, to art, to literature. Huxley spoke strictly and honestly as a man of science, when he related consciousness to the body, as the sound of a clock when it strikes is related to the machinery of the clock. The scientific analysis of a living body reveals nothing but the action of the mechanical and chemical principles. If you analyze it by fire or by cremation, you get gases and vapors and mineral ash, that is all; the main thing about the live body—its organization, its life—you do not get. Of course science knows this; and to account for this missing something, it philosophizes, and relegates it to the interior world of molecular physics—it is all in the way the ultimate particles of matter were joined or compounded, were held together in the bonds of molecular matrimony. What factor or agent or intelligence is active or directive in this molecular marriage of the atoms, science does not inquire. Only philosophy can deal with that problem.

What can science see or find in the brain of man that answers to the soul? Only certain movements of matter in the brain cortex. What difference does it find between inert matter and a living organism? Only a vastly more complex mechanics and chemistry in the latter. A wide difference, not of kind, but of degree. The something we call vitality, that a child recognizes, science does not find; vitality is something sui generis. Scientific analysis cannot show us the difference between the germ cell of a starfish and the germ cell of a man; and yet think of what a world of difference is hidden in those microscopic germs! What force is there in inert matter that can build a machine by the adjustment of parts to each other? We can explain the most complex chemical compounds by the action of chemical forces and chemical affinity, but they cannot explain that adjustment of parts to each other, the coördination of their activities that makes a living machine.

In organized matter there is something that organizes. "The cell itself is an organization of smaller units," and to drive or follow the organizing principle into the last hiding-place is past the power of biological chemistry. What constitutes the guiding force or principle of a living body, adjusting all its parts, making them pull together, making of the circulation one system in which the heart, the veins, the arteries, the lungs, all work to one common end, coördinating several different organs into a digestive system, and other parts into the nervous system, is a mystery that no objective analysis of the body can disclose.

To refer vitality to complexity alone, is to dodge the question. Multiplying the complexity of a machine, say of a watch, any conceivable number of times would not make it any the less a machine, or change it from the automatic order to the vital order. A motor-car is a vastly more complex mechanism than a wheelbarrow, and yet it is not the less a machine. On the other hand, an amœba is a far simpler animal than a man, and yet it is just as truly living. To refer life to complexity does not help us; we want to know what lies back of the complexity—what makes it a new species of complexity.

We cannot explain the origin of living matter by the properties which living matter possesses. There are three things that mechanics and chemistry cannot explain: the relation of the psychical to the physical through the law of the conservation and correlation of forces; the agent or principle that guides the blind chemical and physical forces so as to produce the living body; and the kind of forces that have contributed to the origin of that morphological unit—the cell.

A Western university professor in a recent essay sounds quite a different note on this subject from the one that comes to us from Harvard. Says Professor Otto C. Glaser, of the University of Michigan, in a recent issue of the "Popular Science Monthly": "Does not the fitness of living things; the fact that they perform acts useful to themselves in an environment which is constantly shifting, and often very harsh; the fact that in general everything during development, during digestion, during any of the complicated chains of processes which we find, happens at the right time, in the right place, and to the proper extent; does not all this force us to believe that there is involved something more than mere chemistry and physics?—something, not consciousness necessarily, yet its analogue—a vital x?"

There is this suggestive fact about these recent biological experiments of Dr. Carrel, of the Rockefeller Institute: they seem to prove that the life of a man is not merely the sum of the life of the myriad cells of his body. Stab the man to death, and the cells of his body still live and will continue to live if grafted upon another live man. Probably every part of the body would continue to live and grow indefinitely, in the proper medium. That the cell life should continue after the soul life has ceased is very significant. It seems a legitimate inference from this fact that the human body is the organ or instrument of some agent that is not of the body. The functional or physiological life of the body as a whole, also seems quite independent of our conscious volitional or psychic life. That which repairs and renews the body, heals its wounds, controls and coordinates its parts, adapts it to its environment, carries on its processes during sleep, in fact in all our involuntary life, seems quite independent of the man himself. Is the spirit of a race or a nation, or of the times in which we live, another illustration of the same mysterious entity?

If the vital principle, or vital force, is a fiction, invented to give the mind something to take hold of, we are in no worse case than we are in some other matters. Science tells us that there is no such thing as heat, or light; these are only modes of activity in matter.

In the same way we seem forced to think of life, vitality, as an entity—a fact as real as electricity or light, though it may be only a mode of motion. It may be of physico-chemical origin, as much so as heat, or light; and yet it is something as distinctive as they are among material things, and is involved in the same mystery. Is magnetism or gravitation a real thing? or, in the moral world, is love, charity, or consciousness itself? The world seems to be run by nonentities. Heat, light, life, seem nonentities. That which organizes the different parts or organs of the human body into a unit, and makes of the many organs one organism, is a nonentity. That which makes an oak an oak, and a pine a pine, is a nonentity. That which makes a sheep a sheep, and an ox an ox, is to science a nonentity. To physical science the soul is a nonentity.

There is something in the cells of the muscles that makes them contract, and in the cells of the heart that makes it beat; that something is not active in the other cells of the body. But it is a nonentity. The body is a machine and a laboratory combined, but that which coördinates them and makes them work together—what is that? Another nonentity. That which distinguishes a living machine from a dead machine, science has no name for, except molecular attraction and repulsion, and these are names merely; they are nonentities. Is there not molecular attraction and repulsion in a steam-engine also? And yet it is not alive. What has to supplement the mechanical and the chemical to make matter alive? We have no name for it but the vital, be it an entity or a nonentity. We have no name for a flash of lightning but electricity, be it an entity or a nonentity. We have no name for that which distinguishes a man from a brute, but mind, soul, be it an entity or a nonentity. We have no name for that which distinguishes the organic from the inorganic but vitality, be it an entity or a nonentity.

VII

Without metaphysics we can do nothing; without mental concepts, where are we? Natural selection is as much a metaphysical phrase as is consciousness, or the subjective and the objective. Natural selection is not an entity, it is a name for what we conceive of as a process. It is natural rejection as well. The vital principle is a metaphysical concept; so is instinct; so is reason; so is the soul; so is God.

Many of our concepts have been wrong. The concept of witches, of disease as the work of evil spirits, of famine and pestilence as the visitation of the wrath of God, and the like, were unfounded. Science sets us right about all such matters. It corrects our philosophy, but it cannot dispense with the philosophical attitude of mind. The philosophical must supplement the experimental.

In fact, in considering this question of life, it is about as difficult for the unscientific mind to get along without postulating a vital principle or force—which, Huxley says, is analogous to the idea of a principle of aquosity in water—as it is to walk upon the air, or to hang one's coat upon a sunbeam. It seems as if something must breathe upon the dead matter, as at the first, to make it live. Yet if there is a distinct vital force it must be correlated with physical force, it must be related causally to the rest. The idea of a vital force as something new and distinct and injected into matter from without at a given time and place in the earth's history, must undoubtedly be given up. Instead of escaping from mechanism, this notion surrenders one into the hands of mechanism, since to supplement or reinforce a principle with some other principle from without, is strictly a mechanical procedure. But the conception of vitality as potential in matter, or of the whole universe as permeated with spirit, which to me is the same thing, is a conception that takes life out of the categories of the fortuitous and the automatic.

No doubt but that all things in the material world are causally related, no doubt of the constancy of matter and force, no doubt but that all phenomena are the result of natural principles, no doubt that the living arose from the non-living, no doubt that the evolution process was inherent in the constitution of the world; and yet there is a mystery about it all that is insoluble. The miracle of vitality takes place behind a veil that we cannot penetrate, in the inmost sanctuary of the molecules of matter, in that invisible, imaginary world on the borderland between the material and the immaterial. We may fancy that it is here that the psychical effects its entrance into the physical—that spirit weds matter—that the creative energy kindles the spark we call vitality. At any rate, vitality evidently begins in that inner world of atoms and molecules; but whether as the result of their peculiar and very complex compounding or as the cause of the compounding—how are we ever to know? Is it not just as scientific to postulate a new principle, the principle of vitality, as to postulate a new process, or a new behavior of an old principle? In either case, we are in the world of the unverifiable; we take a step in the dark. Most of us, I fancy, will sympathize with George Eliot, who says in one of her letters: "To me the Development Theory, and all other explanations of processes by which things came to be, produce a feeble impression compared with the mystery that lies under the processes."

V

SCIENTIFIC VITALISM

I

All living bodies, when life leaves them, go back to the earth from whence they came. What was it in the first instance that gathered their elements from the earth and built them up into such wonderful mechanisms? If we say it was nature, do we mean by nature a physical force or an immaterial principle? Did the earth itself bring forth a man, or did something breathe upon the inert clay till it became a living spirit?

As life is a physical phenomenon, appearing in a concrete physical world, it is, to that extent, within the domain of physical science, and appeals to the scientific mind. Physical science is at home only in the experimental, the verifiable. Its domain ends where that of philosophy begins.

The question of how life arose in a universe of dead matter is just as baffling a question to the ordinary mind, as how the universe itself arose. If we assume that the germs of life drifted to us from other spheres, propelled by the rays of the sun, or some other celestial agency, as certain modern scientific philosophers have assumed, we have only removed the mystery farther away from us. If we assume that it came by spontaneous generation, as Haeckel and others assume, then we are only cutting a knot which we cannot untie. The god of spontaneous generation is as miraculous as any other god. We cannot break the causal sequence without a miracle. If something came from nothing, then there is not only the end of the problem, but also the end of our boasted science.

Science is at home in discussing all the material manifestations of life—the parts played by colloids and ferments, by fluids and gases, and all the organic compounds, and by mechanical and chemical principles; it may analyze and tabulate all life processes, and show the living body as a most wonderful and complex piece of mechanism, but before the question of the origin of life itself it stands dumb, and, when speaking through such a man as Tyndall, it also stands humble and reverent. After Tyndall had, to his own satisfaction, reduced all like phenomena to mechanical attraction and repulsion, he stood with uncovered head before what he called the "mystery and miracle of vitality." The mystery and miracle lie in the fact that in the organic world the same elements combine with results so different from those of the inorganic world. Something seems to have inspired them with a new purpose. In the inorganic world, the primary elements go their ceaseless round from compound to compound, from solid to fluid or gaseous, and back again, forming the world of inert matter as we know it, but in the organic world the same elements form thousands of new combinations unknown to them before, and thus give rise to the myriad forms of life that inhabit the earth.

The much-debated life question has lately found an interesting exponent in Professor Benjamin Moore, of the University of Liverpool. His volume on the subject in the "Home University Library" is very readable, and, in many respects, convincing. At least, so far as it is the word of exact science on the subject it is convincing; so far as it is speculative, or philosophical, it is or is not convincing, according to the type of mind of the reader. Professor Moore is not a bald mechanist or materialist like Professor Loeb, or Ernst Haeckel, nor is he an idealist or spiritualist, like Henri Bergson or Sir Oliver Lodge. He may be called a scientific vitalist. He keeps close to lines of scientific research as these lines lead him through the maze of the primordial elements of matter, from electron to atom, from atom to molecule, from molecule to colloid, and so up to the border of the living world. His analysis of the processes of molecular physics as they appear in the organism leads him to recognize and to name a new force, or a new manifestation of force, which he hesitates to call vital, because of the associations of this term with a prescientific age, but which he calls "biotic energy."

Biotic energy is peculiar to living bodies, and "there are precisely the same criteria for its existence," says Professor Moore, "as for the existence of any one of the inorganic energy types, viz., a set of discrete phenomena; and its nature is as mysterious to us as the cause of any one of these inorganic forms about which also we know so little. "It is biotic energy which guides the development of the ovum, which regulates the exchanges of the cell, and causes such phenomena as nerve impulse, muscular contraction, and gland secretion, and it is a form of energy which arises in colloidal structures, just as magnetism appears in iron, or radio-activity in uranium or radium, and in its manifestations it undergoes exchanges with other forms of energy, in the same manner as these do among one another."

Like Professor Henderson, Professor Moore concedes to the vitalists about all they claim—namely, that there is some form of force or manifestation of energy peculiar to living bodies, and one that cannot be adequately described in terms of physics and chemistry. Professor Moore says this biotic energy "arises in colloidal structures," and so far as biochemistry can make out, arises spontaneously and gives rise to that marvelous bit of mechanism, the cell. In the cell appears "a form of energy unknown outside life processes which leads the mazy dance of life from point to point, each new development furnishing a starting point for the next one." It not only leads the dance along our own line of descent from our remote ancestors—it leads the dance along the long road of evolution from the first unicellular form in the dim palæozoic seas to the complex and highly specialized forms of our own day.

The secret of this life force, or biotic energy, according to Professor Moore, is in the keeping of matter itself. The steps or stages from the depths of matter by which life arose, lead up from that imaginary something, the electron, to the inorganic colloids, or to the crystallo-colloids, which are the threshold of life, each stage showing some new transformation of energy. There must be an all-potent energy transformation before we can get chemical energy out of physical energy, and then biotic energy out of chemical energy. This transformation of inorganic energy into life energy cannot be traced or repeated in the laboratory, yet science believes the secret will sometime be in its hands. It is here that the materialistic philosophers, such as Professors Moore and Loeb, differ from the spiritualistic philosophers, such as Bergson, Sir Oliver Lodge, Professor Thompson, and others.

Professor Moore has no sympathy with those narrow mechanistic views that see in the life processes "no problems save those of chemistry and physics." "Each link in the living chain may be physico-chemical, but the chain as a whole, and its purpose, is something else." He draws an analogy from the production of music in which purely physical factors are concerned; the laws of harmonics account for all; but back of all is something that is not mechanical and chemical—there is the mind of the composer, and the performers, and the auditors, and something that takes cognizance of the whole effect. A complete human philosophy cannot be built upon physical science alone. He thinks the evolution of life from inert matter is of the same type as the evolution of one form of matter from another, or the evolution of one form of energy from another—a mystery, to be sure, but little more startling in the one case than in the other. "The fundamental mystery lies in the existence of those entities, or things, which we call matter and energy," out of the play and interaction of which all life phenomena have arisen. Organic evolution is a series of energy exchanges and transformations from lower to higher, but science is powerless to go behind the phenomena presented and name or verify the underlying mystery. Only philosophy can do this. And Professor Moore turns philosopher when he says there is beauty and design in it all, "and an eternal purpose which is ever progressing."

Bergson sets forth his views of evolution in terms of literature and philosophy. Professor Moore embodies similar views in his volume, set forth in terms of molecular science. Both make evolution a creative and a continuous process. Bergson lays the emphasis upon the cosmic spirit interacting with matter. Professor Moore lays the emphasis upon the indwelling potencies of matter itself (probably the same spirit conceived of in different terms). Professor Moore philosophizes as truly as does Bergson when he says "there must exist a whole world of living creatures which the microscope has never shown us, leading up to the bacteria and the protozoa. The brink of life lies not at the production of protozoa and bacteria, which are highly developed inhabitants of our world, but away down among the colloids; and the beginning of life was not a fortuitous event occurring millions of years ago and never again repeated, but one which in its primordial stages keeps on repeating itself all the time in our generation. So that if all intelligent creatures were by some holocaust destroyed, up out of the depths in process of millions of years, intelligent beings would once more emerge." This passage shows what a speculative leap or flight the scientific mind is at times compelled to take when it ventures beyond the bounds of positive methods. It is good philosophy, I hope, but we cannot call it science. Thrilled with cosmic emotion, Walt Whitman made a similar daring assertion:—

"There is no stoppage, and never can be stoppage,

If I, you, and the worlds, and all beneath or upon their surfaces,

were this moment reduced back to a pallid float, it would

not avail in the long run,

We should surely bring up again where we now stand,

And surely go as much farther, and then farther and farther."

II

Evolution is creative, whether it works in matter—as Bergson describes, or whether its path lies up through electrons and atoms and molecules, as Professor Moore describes. There is something that creates and makes matter plastic to its will. Whether we call matter "the living garment of God," as Goethe did, or a reservoir of creative energy, as Tyndall and his school did, and as Professor Moore still does, we are paying homage to a power that is super-material. Life came to our earth, says Professor Moore, through a "well-regulated orderly development," and it "comes to every mother earth of the universe in the maturity of her creation when the conditions arrive within suitable limits." That no intelligent beings appeared upon the earth for millions upon millions of years, that for whole geologic ages there was no creature with more brains than a snail possesses, shows the almost infinitely slow progress of development, and that there has been no arbitrary or high-handed exercise of creative power. The universe is not run on principles of modern business efficiency, and man is at the head of living forms, not by the fiat of some omnipotent power, some superman, but as the result of the operation of forces that balk at no delay, or waste, or failure, and that are dependent upon the infinitely slow ripening and amelioration of both cosmic and terrestrial conditions.

We do not get rid of God by any such dictum, but we get rid of the anthropomorphic views which we have so long been wont to read into the processes of nature. We dehumanize the universe, but we do not render it the less grand and mysterious. Professor Moore points out to us how life came to a cooling planet as soon as the temperature became low enough for certain chemical combinations to appear. There must first be oxides and saline compounds, there must be carbonates of calcium and magnesium, and the like. As the temperature falls, more and more complex compounds, such as life requires, appear; till, in due time, carbon dioxide and water are at hand, and life can make a start. At the white heat of some of the fixed stars, the primary chemical elements are not yet evolved; but more and more elements appear, and more and more complex compounds are formed as the cooling process progresses.

"This note cannot be too strongly sounded, that as matter is allowed capacity for assuming complex forms, those complex forms appear. As soon as oxides can be there, oxides appear; when temperature admits of carbonates, then carbonates are forthwith formed. These are experiments which any chemist can to-day repeat in a crucible. And on a cooling planet, as soon as temperature will admit the presence of life, then life appears, as the evidence of geology shows us." When we speak of the beginning of life, it is not clear just what we mean. The unit of all organized bodies is the cell, but the cell is itself an organized body, and must have organic matter to feed upon. Hence the cell is only a more complex form of more primitive living matter. As we go down the scale toward the inorganic, can we find the point where the living and the non-living meet and become one? "Life had to surge a long way up from the depths before a green plant cell came into being." When the green plant cell was found, life was fairly launched. This plant cell, in the form of chlorophyll, by the aid of water and the trace of carbon dioxide in the air, began to store up the solar energy in fruit and grain and woody tissue, and thus furnish power to run all forms of life machinery.

The materialists or naturalists are right in urging that we live in a much more wonderful universe than we have ever imagined, and that in matter itself sleep potencies and possibilities not dreamt of in our philosophy. The world of complex though invisible activities which science reveals all about us, the solar and stellar energies raining upon us from above, the terrestrial energies and influences playing through us from below, the transformations and transmutations taking place on every hand, the terrible alertness and potency of the world of inert matter as revealed by a flash of lightning, the mysteries of chemical affinity, of magnetism, of radio-activity, all point to deep beneath deep in matter itself. It is little wonder that men who dwell habitually upon these things and are saturated with the spirit and traditions of laboratory investigation, should believe that in some way matter itself holds the mystery of the origin of life. On the other hand, a different type of mind, the more imaginative, artistic, and religious type, recoils from the materialistic view.

The sun is the source of all terrestrial energy, but the different forms that energy takes—in the plant, in the animal, in the brain of man—this type of mind is bound to ask questions about that. Gravity pulls matter down; life lifts it up; chemical forces pull it to pieces; vital forces draw it together and organize it; the winds and the waters dissolve and scatter it; vegetation recaptures and integrates it and gives it new qualities. At every turn, minds like that of Sir Oliver Lodge are compelled to think of life as a principle or force doing something with matter. The physico-chemical forces will not do in the hands of man what they do in the hands of Nature. Such minds, therefore, feel justified in thinking that something which we call "the hands of Nature," plays a part—some principle or force which the hands of man do not hold.

VI

A BIRD OF PASSAGE

I

There is one phase of the much-discussed question of the nature and origin of life which, so far as I know, has not been considered either by those who hold a brief for the physico-chemical view or by those who stand for some form of vitalism or idealism. I refer to the small part that life plays in the total scheme of things. The great cosmic machine would go on just as well without it. Its relation to the whole appears to be little different from that of a man to the train in which he journeys. Life rides on the mechanical and chemical forces, but it does not seem to be a part of them, nor identical with them, because they were before it, and will continue after it is gone.

The everlasting, all-inclusive thing in this universe seems to be inert matter with the energy it holds; while the slight, flitting, casual thing seems to be living matter. The inorganic is from all eternity to all eternity; it is distributed throughout all space and endures through all time, while the organic is, in comparison, only of the here and the now; it was not here yesterday, and it may not be here to-morrow; it comes and goes. Life is like a bird of passage which alights and tarries for a time and is gone, and the places where it perched and nested and led forth its brood know it no more. Apparently it flits from world to world as the great cosmic spring comes to each, and departs as the cosmic winter returns to each. It is a visitor, a migrant, a frail, timid thing, which waits upon the seasons and flees from the coming tempests and vicissitudes.

How casual, uncertain, and inconsequential the vital order seems in our own solar system—a mere incident or by-product in its cosmic evolution! Astronomy sounds the depths of space, and sees only mechanical and chemical forces at work there. It is almost certain that only a small fraction of the planetary surfaces is the abode of life. On the earth alone, of all the great family of planets and satellites, is the vital order in full career. It may yet linger upon Mars, but it is evidently waning. On the inferior planets it probably had its day long ago, while it must be millions of years before it comes to the superior planets, if it ever comes to them. What a vast, inconceivable outlay of time and energy for such small returns! Evidently the vital order is only an episode, a transient or secondary phase of matter in the process of sidereal evolution. Astronomic space is strewn with dead worlds, as a New England field is with drift boulders. That life has touched and tarried here and there upon them can hardly be doubted, but if it is anything more than a passing incident, an infant crying in the night, a flush of color upon the cheek, a flower blooming by the wayside, appearances are against it.

We read our astronomy and geology in the light of our enormous egotism, and appropriate all to ourselves; but science sees in our appearance here a no more significant event than in the foam and bubbles that whirl and dance for a moment upon the river's current. The bubbles have their reason for being; all the mysteries of molecular attraction and repulsion may be involved in their production; without the solar energy, and the revolution of the earth upon its axis, they would not appear; and yet they are only bubbles upon the river's current, as we are bubbles upon the stream of energy that flows through the universe. Apparently the cosmic game is played for us no more than for the parasites that infest our bodies, or for the frost ferns that form upon our window-panes in winter. The making of suns and systems goes on in the depths of space, and doubtless will go on to all eternity, without any more reference to the vital order than to the chemical compounds.

The amount of living matter in the universe, so far as we can penetrate it, compared with the non-living, is, in amount, like a flurry of snow that whitens the fields and hills of a spring morning compared to the miles of rock and soil beneath it; and with reference to geologic time it is about as fleeting. In the vast welter of suns and systems in the heavens above us, we see only dead matter, and most of it is in a condition of glowing metallic vapor. There are doubtless living organisms upon some of the invisible planetary bodies, but they are probably as fugitive and temporary as upon our own world. Much of the surface of the earth is clothed in a light vestment of life, which, back in geologic time, seems to have more completely enveloped it than at present, as both the arctic and the antarctic regions bear evidence in their coal-beds and other fossil remains of luxuriant vegetable growths.

Strip the earth of its thin pellicle of soil, thinner with reference to the mass than is the peel to the apple, and you have stripped it of its life. Or, rob it of its watery vapor and the carbon dioxide in the air, both stages in its evolution, and you have a dead world. The huge globe swings through space only as a mass of insensate rock. So limited and evanescent is the world of living matter, so vast and enduring is the world of the non-living. Looked at in this way, in the light of physical science, life, I repeat, seems like a mere passing phase of the cosmic evolution, a flitting and temporary stage of matter which it passes through in the procession of changes on the surface of a cooling planet. Between the fiery mist of the nebula, and the frigid and consolidated globe, there is a brief span, ranging over about one hundred and twenty degrees of temperature, where life appears and organic evolution takes place. Compared with the whole scale of temperature, from absolute zero to the white heat of the hottest stars, it is about a hand's-breadth compared to a mile.

Life processes cease, but chemical and mechanical processes go on forever. Life is as fugitive and uncertain as the bow in the clouds, and, like the bow in the clouds, is confined to a limited range of conditions. Like the bow, also, it is a perpetual creation, a constant becoming, and its source is not in the matter through which it is manifested, though inseparable from it. The material substance of life, like the rain-drops, is in perpetual flux and change; it hangs always on the verge of dissolution and vanishes when the material conditions fail, to be renewed again when they return. We know, do we not? that life is as literally dependent upon the sun as is the rainbow, and equally dependent upon the material elements; but whether the physical conditions sum up the whole truth about it, as they do with the bow, is the insoluble question. Science says "Yes," but our philosophy and our religion say "No." The poets and the prophets say "No," and our hopes and aspirations say "No."

II

Where, then, shall we look for the key to this mysterious thing we call life? Modern biochemistry will not listen to the old notion of a vital force—that is only a metaphysical will-o'-the-wisp that leaves us floundering in the quagmire. If I question the forces about me, what answer do I get? Molecular attraction and repulsion seem to say, "It is not in us; we are as active in the clod as in the flower." The four principal elements—oxygen, nitrogen, hydrogen, and carbon—say, "It is not in us, because we are from all eternity, and life is not; we form only its physical basis." Warmth and moisture say, "It is not in us; we are only its faithful nurses and handmaidens." The sun says: "It is not in me; I shine on dead worlds as well. I but quicken life after it is planted." The stars say, "It is not in us; we have seen life come and go among myriads of worlds for untold ages." No questioning of the heavens above nor of the earth below can reveal to us the secret we are in quest of.

I can fancy brute matter saying to life: "You tarry with me at your peril. You will always be on the firing-line of my blind, contending forces; they will respect you not; you must take your chances amid my flying missiles. My forces go their eternal round without variableness or shadow of turning, and woe to you if you cross their courses. You may bring all your gods with you—gods of love, mercy, gentleness, altruism; but I know them not. Your prayers will fall upon ears of stone, your appealing gesture upon eyes of stone, your cries for mercy upon hearts of stone. I shall be neither your enemy nor your friend. I shall be utterly indifferent to you. My floods will drown you, my winds wreck you, my fires burn you, my quicksands suck you down, and not know what they are doing. My earth is a theatre of storms and cyclones, of avalanches and earthquakes, of lightnings and cloudbursts; wrecks and ruins strew my course. All my elements and forces are at your service; all my fluids and gases and solids; my stars in their courses will fight on your side, if you put and keep yourself in right relations to them. My atoms and electrons will build your houses, my lightning do your errands, my winds sail your ships, on the same terms. You cannot live without my air and my water and my warmth; but each of them is a source of power that will crush or engulf or devour you before it will turn one hair's-breadth from its course. Your trees will be uprooted by my tornadoes, your fair fields will be laid waste by floods or fires; my mountains will fall on your delicate forms and utterly crush and bury them; my glaciers will overspread vast areas and banish or destroy whole tribes and races of your handiwork; the shrinking and wrinkling crust of my earth will fold in its insensate bosom vast forests of your tropical growths, and convert them into black rock, and I will make rock of the myriad forms of minute life with which you plant the seas; through immense geologic ages my relentless, unseeing, unfeeling forces will drive on like the ploughshare that buries every flower and grass-blade and tiny creature in its path. My winds are life-giving breezes to-day, and the besom of destruction to-morrow; my rains will moisten and nourish you one day, and wash you into the gulf the next; my earthquakes will bury your cities as if they were ant-hills. So you must take your chances, but the chances are on your side. I am not all tempest, or flood, or fire, or earthquake. Your career will be a warfare, but you will win more battles than you will lose. But remember, you are nothing to me, while I am everything to you. I have nothing to lose or gain, while you have everything to gain. Without my soils and moisture and warmth, without my carbon and oxygen and nitrogen and hydrogen, you can do or be nothing; without my sunshine you perish; but you have these things on condition of effort and struggle. You have evolution on condition of pain and failure and the hazard of the warring geologic ages. Fate and necessity rule in my realm. When you fail, or are crushed or swallowed by my remorseless forces, do not blame my gods, or your own; there is no blame, there is only the price to be paid: the hazards of invading the closed circle of my unseeing forces."

In California I saw an epitome of the merciless way inorganic Nature deals with life. An old, dried, and hardened asphalt lake near Los Angeles tells a horrible tale of animal suffering and failure. It had been a pit of horrors for long ages; it was Nature concentrated—her wild welter of struggling and devouring forms through the geologic ages made visible and tangible in a small patch of mingled pitch and animal bones. There was nearly as much bone as pitch. The fate of the unlucky flies that alight upon tangle-foot fly-paper in our houses had been the fate of the victims that had perished here. How many wild creatures had turned appealing eyes to the great unheeding void as they felt themselves helpless and sinking in this all-engulfing pitch! In like manner how many human beings in storms and disasters at sea and in flood and fire upon land have turned the same appealing look to the unpitying heavens! There is no power in the world of physical forces, or apart from our own kind, that heeds us or turns aside for us, or bestows one pitying glance upon us. Life has run, and still runs, the gantlet of a long line of hostile forces, and escapes by dint of fleetness of foot, or agility in dodging, or else by toughness of fibre.

Yet here we are; here is love and charity and mercy and intelligence; the fair face of childhood, the beautiful face of youth, the clear, strong face of manhood and womanhood, and the calm, benign face of old age, seen, it is true, as against a background of their opposites, but seeming to indicate something above chance and change at the heart of Nature. Here is life in the midst of death; but death forever playing into the hands of life; here is the organic in the midst of the inorganic, at strife with it, hourly crushed by it, yet sustained and kept going by its aid.

III

Vitality is only a word, but it marks a class of phenomena in nature that stands apart from all merely mechanical manifestations in the universe. The cosmos is a vast machine, but in this machine—this tremendous complex of physical forces—there appears, at least on this earth, in the course of its evolution, this something, or this peculiar manifestation of energy, that we call vital. Apparently it is a transient phase of activity in matter, which, unlike other chemical and physical activities, has its beginning and its ending, and out of which have arisen all the myriad forms of terrestrial life. The merely material forces, blind and haphazard from the first, did not arise in matter; they are inseparable from it; they are as eternal as matter itself; but the activities called vital arose in time and place, and must eventually disappear as they arose, while the career of the inorganic elements goes on as if life had never visited the sphere. Was it, or is it, a visitation—something ab extra that implies super-mundane, or supernatural, powers?

Added to this wonder is the fact that the vital order has gone on unfolding through the geologic ages, mounting from form to form, or from order to order, becoming more and more complex, passing from the emphasis of size of body, to the emphasis of size of brain, and finally from instinct and reflex activities to free volition, and the reason and consciousness of man; while the purely physical and chemical forces remain where they began. There has been endless change among them, endless shifting of the balance of power, but always the tendency to a dead equilibrium, while the genius of the organic forces has been in the power to disturb the equilibrium and to ride into port on the crest of the wave it has created, or to hang forever between the stable and the unstable.

So there we are, confronted by two apparently contrary truths. It is to me unthinkable that the vital order is not as truly rooted in the constitution of things as are the mechanical and chemical orders; and yet, here we are face to face with its limited, fugitive, or transitional character. It comes and goes like the dews of the morning; it has all the features of an exceptional, unexpected, extraordinary occurrence—of miracle, if you will; but if the light which physical science turns on the universe is not a delusion, if the habit of mind which it begets is not a false one, then life belongs to the same category of things as do day and night, rain and sun, rest and motion. Who shall reconcile these contradictions?

Huxley spoke for physical science when he said that he did not know what it was that constituted life—what it was that made the "wonderful difference between the dead particles and the living particles of matter appearing in other respects identical." He thought there might be some bond between physico-chemical phenomena, on the one hand, and vital phenomena, on the other, which philosophers will some day find out. Living matter is characterized by "spontaneity of action," which is entirely absent from inert matter. Huxley cannot or does not think of a vital force distinct from all other forces, as the cause of life phenomena, as so many philosophers have done, from Aristotle down to our day. He finds protoplasm to be the physical basis of life; it is one in both the vegetable and animal worlds; the animal takes it from the vegetable, and the vegetable, by the aid of sunlight, takes or manufactures it from the inorganic elements. But protoplasm is living matter. Before there was any protoplasm, what brought about the stupendous change of the dead into the living? Protoplasm makes more protoplasm, as fire makes more fire, but what kindled the first spark of this living flame? Here we corner the mystery, but it is still a mystery that defies us. Cause and effect meet and are lost in each other. Science cannot admit a miracle, or a break in the continuity of life, yet here it reaches a point where no step can be taken. Huxley's illustrations do not help his argument. "Protoplasm," he says, "is the clay of the potter; which, bake it and paint it as he will, remains clay, separated by artifice, and not by nature, from the commonest brick or sun-dried clod." Clay is certainly the physical basis of the potter's art, but would there be any pottery in the world if it contained only clay? Do we not have to think of the potter? In the same way, do we not have to think of something that fashions these myriad forms of life out of protoplasm?—and back of that, of something that begat protoplasm out of non-protoplasmic matter, and started the flame of life going? Life accounts for protoplasm, but what accounts for life? We have to think of the living clay as separated by Nature from the inert "sun-dried clod." There is something in the one that is not in the other. There is really no authentic analogy between the potter's art and Nature's art of life.

The force of the analogy, if it has any, drives us to the conclusion that life is an entity, or an agent, working upon matter and independent of it.

There is more wit than science in Huxley's question, "What better philosophical status has vitality than aquosity?" There is at least this difference: When vitality is gone, you cannot recall it, or reproduce it by your chemistry; but you can recombine the two gases in which you have decomposed water, any number of times, and get your aquosity back again; it never fails; it is a power of chemistry. But vitality will not come at your beck; it is not a chemical product, at least in the same sense that water is; it is not in the same category as the wetness or liquidity of water. It is a name for a phenomenon—the most remarkable phenomenon in nature. It is one that the art of man is powerless to reproduce, while water may be made to go through its cycle of change—solid, fluid, vapor, gas—and always come back to water. Well does the late Professor Brooks, of Johns Hopkins, say 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." Does not Ray Lankester, the irate champion of the mechanistic view of life, say essentially the same thing when he calls man the great Insurgent in Nature's camp—"crossing her courses, reversing her processes, and defeating her ends?"

Life appears like the introduction of a new element or force or tendency into the cosmos. Henceforth the elements go new ways, form new compounds, build up new forms, and change the face of nature. Rivers flow where they never would have flowed without it, mountains fall in a space of time during which they never would have fallen; barriers arise, rough ways are made smooth, a new world appears—the world of man's physical and mental activities.

If the gods of the inorganic elements are neither for nor against us, but utterly indifferent to us, how came we here? Nature's method is always from the inside, while ours is from the outside; hers is circular while ours is direct. We think, as Bergson says, of things created, and of a thing that creates, but things in nature are not created, they are evolved; they grow, and the thing that grows is not separable from the force that causes it to grow. The water turns the wheel, and can be shut off or let on. This is the way of the mechanical world. But the wheels in organic nature go around from something inside them, a kind of perpetual motion, or self-supplying power. They are not turned, they turn; they are not repaired, they repair. The nature of living things cannot be interpreted by the laws of mechanical and chemical things, though mechanics and chemistry play the visible, tangible part in them. If we must discard the notion of a vital force, we may, as Professor Hartog suggests, make use of the term "vital behavior."

Of course man tries everything by himself and his own standards. He knows no intelligence but his own, no prudence, no love, no mercy, no justice, no economy, but his own, no god but such a one as fits his conception.

In view of all these things, how man got here is a problem. Why the slender thread of his line of descent was not broken in the warrings and upheavals of the terrible geologic ages, what power or agent took a hand in furthering his development, is beyond the reach of our biologic science.

Man's is the only intelligence, as we understand the word, in the universe, and his intelligence demands something akin to intelligence in the nature from which he sprang.

VII

LIFE AND MIND

I

There are three kinds of change in the world in which we live—physical and mechanical change which goes on in time and place among the tangible bodies about us, chemical change which goes on in the world of hidden molecules and atoms of which bodies are composed, and vital change which involves the two former, but which also involves the mysterious principle or activity which we call life. Life comes and goes, but the physical and chemical orders remain. The vegetable and animal kingdoms wax and wane, or disappear entirely, but the physico-chemical forces are as indestructible as matter itself. This fugitive and evanescent character of life, the way it uses and triumphs over the material forces, setting up new chemical activities in matter, sweeping over the land-areas of the earth like a conflagration, lifting the inorganic elements up into myriads of changing and beautiful forms, instituting a vast number of new chemical processes and compounds, defying the laboratory to reproduce it or kindle its least spark—a flame that cannot exist without carbon and oxygen, but of which carbon and oxygen do not hold the secret, a fire reversed, building up instead of pulling down, in the vegetable with power to absorb and transmute the inorganic elements into leaves and fruit and tissue; in the animal with power to change the vegetable products into bone and muscle and nerve and brain, and finally into thought and consciousness; run by the solar energy and dependent upon it, yet involving something which the sunlight cannot give us; in short, an activity in matter, or in a limited part of matter, as real as the physico-chemical activity, but, unlike it, defying all analysis and explanation and all our attempts at synthesis. It is this character of life, I say, that so easily leads us to look upon it as something ab extra, or super-added to matter, and not an evolution from it. It has led Sir Oliver Lodge to conceive of life as a distinct entity, existing independent of matter, and it is this conception that gives the key to Henri Bergson's wonderful book, "Creative Evolution."

There is possibly or probably a fourth change in matter, physical in its nature, but much more subtle and mysterious than any of the physical changes which our senses reveal to us. I refer to radioactive change, or to the atomic transformation of one element into another, such as the change of radium into helium, and the change of helium into lead—a subject that takes us to the borderland between physics and chemistry where is still debatable ground.

I began by saying that there were three kinds of changes in matter—the physical, the chemical, and the vital. But if we follow up this idea and declare that there are three kinds of force also, claiming this distinction for the third term of our proposition, we shall be running counter to the main current of recent biological science. "The idea that a peculiar 'vital force' acts in the chemistry of life," says Professor Soddy, "is extinct."

"Only chemical and physical agents influence the vital processes," says Professor Czapek, of the University of Prague, "and we need no longer take refuge in mysterious 'vital forces' when we want to explain these."

Tyndall was obliged to think of a force that guided the molecules of matter into the special forms of a tree. This force was in the ultimate particles of matter. But when he came to the brain and to consciousness, he said a new product appeared that defies mechanical treatment.

The attempt of the biological science of our time to wipe out all distinctions between the living and the non-living, solely because scientific analysis reveals no difference, is a curious and interesting phenomenon.

Professor Schäfer, in his presidential address before the British Association in 1912, argued that all the main characteristics of living matter, such as assimilation and disassimilation, growth and reproduction, spontaneous and amœboid movement, osmotic pressure, karyokinesis, etc., were equally apparent in the non-living; therefore he concluded that life is only one of the many chemical reactions, and that it is not improbable that it will yet be produced by chemical synthesis in the laboratory. The logic of the position taken by Professor Schäfer and of the school to which he belongs, demands this artificial production of life—an achievement that seems no nearer than it did a half-century ago. When it has been attained, the problem will be simplified, but the mystery of life will by no means have been cleared up. One follows these later biochemists in working out their problem of the genesis of life with keen interest, but always with a feeling that there is more in their conclusions than is justified by their premises. For my own part, I am convinced that whatever is, is natural, but to obtain life I feel the need of something of a different order from the force that evokes the spark from the flint and the steel, or brings about the reaction of chemical compounds. If asked to explain what this something is that is characteristic of living matter, I should say intelligence.

The new school of biologists start with matter that possesses extraordinary properties—with matter that seems inspired with the desire for life, and behaving in a way that it never will behave in the laboratory. They begin with the earth's surface warm and moist, the atmosphere saturated with watery vapor and carbon dioxide and many other complex unstable compounds; then they summon all the material elements of life—carbon, oxygen, hydrogen, and nitrogen, with a little sodium, chlorine, iron, sulphur, phosphorus, and others—and make these run together to form a jelly-like body called a colloid; then they endow this jelly mass with the power of growth, and of subdivision when it gets too large; they make it able to absorb various unstable compounds from the air, giving it internal stores of energy, "the setting free of which would cause automatic movements in the lump of jelly." Thus they lay the foundations of life. This carbonaceous material with properties of movement and subdivision due to mechanical and physical forces is the immediate ancestor of the first imaginary living being, the protobion. To get this protobion the chemists summon a reagent known as a catalyser. The catalyser works its magic on the jelly mass. It sets up a wonderful reaction by its mere presence, without parting with any of its substance. Thus, if a bit of platinum which has this catalytic power is dropped into a vessel containing a mixture of oxygen and hydrogen, the two gases instantly unite and form water. A catalyser introduced in the primordial jelly liberates energy and gives the substance power to break up the various complex unstable compounds into food, and promote growth and subdivision. In fact, it awakens or imparts a vital force and leads to "indefinite increase, subdivision, and movement."