IV
Bergson says the intellect is characterized by a natural inability to understand life. Certain it is, I think, that science alone cannot grasp its mystery. We must finally appeal to philosophy; we must have recourse to ideal values--to a non-scientific or super-scientific principle. We cannot live intellectually or emotionally upon science alone. Science reveals to us the relations and inter-dependence of things in the physical world and their relations to our physical well-being; philosophy reveals their relations to our mental and spiritual life, their meanings and their ideal values. Poor, indeed, is the man who has no philosophy, no commanding outlook over the tangles and contradictions of the world of sense. There is probably some unknown and unknowable factor involved in the genesis of life, but that that factor or principle does not belong to the natural, universal order is unthinkable. Yet to fail to see that what we must call intelligence pervades and is active in all organic nature is to be spiritually blind.
But to see it as something foreign to or separable from nature is to do violence to our faith in the constancy and sufficiency of the natural order. One star differeth from another in glory. There are degrees of mystery in the universe. The most mystifying thing in inorganic nature is electricity,--that disembodied energy that slumbers in the ultimate particles of matter, unseen, unfelt, unknown, till it suddenly leaps forth with such terrible vividness and power on the face of the storm, or till we summon it through the transformation of some other form of energy. A still higher and more inscrutable mystery is life, that something which clothes itself in each infinitely varied and beautiful as well as unbeautiful form of matter. We can evoke electricity at will from many different sources, but we can evoke life only from other life; the biogenetic law is inviolable.
Professor Soddy says, "Natural philosophy may explain a rainbow but not a rabbit." There is no secret about a rainbow; we can produce it at will out of perfectly colorless beginnings. "But nothing but rabbits will or can produce a rabbit, a proof again that we cannot say what a rabbit is, though we may have a perfect knowledge of every anatomical and microscopic detail."
To regard life as of non-natural origin puts it beyond the sphere of legitimate inquiry; to look upon it as of natural origin, or as bound in a chain of chemical sequences, as so many late biochemists do, is still to put it where our science cannot unlock the mystery. If we should ever succeed in producing living matter in our laboratories, it would not lessen the mystery any more than the birth of a baby in the household lessens the mystery of generation. It only brings it nearer home.
V
What is peculiar to organic nature is the living cell. Inside the cell, doubtless, the same old chemistry and physics go on--the same universal law of the transformation of energy is operative. In its minute compa.s.s the trans.m.u.tation of the inorganic into the organic, which const.i.tutes what Tyndall called "the miracle and the mystery of vitality," is perpetually enacted. But what is the secret of the cell itself? Science is powerless to tell us. You may point out to your heart"s content that only chemical and physical forces are discoverable in living matter; that there is no element or force in a plant that is not in the stone beside which it grew, or in the soil in which it takes root; and yet, until your chemistry and your physics will enable you to produce the living cell, or account for its mysterious self-directed activities, your science avails not. "Living cells," says a late European authority, "possess most effective means to accelerate reactions and to cause surprising chemical results."
Behold the four princ.i.p.al elements forming stones and soils and water and air for whole geologic or astronomic ages, and then behold them forming plants and animals, and finally forming the brains that give us art and literature and philosophy and modern civilization. What prompted the elements to this new and extraordinary behavior? Science is dumb before such a question.
Living bodies are immersed in physical conditions as in a sea. External agencies--light, moisture, air, gravity, mechanical and chemical influences--cause great changes in them; but their power to adapt themselves to these changes, and profit by them, remains unexplained.
Are morphological processes identical with chemical ones?
In the inorganic world we everywhere see mechanical adjustment, repose, stability, equilibrium, through the action and interaction of outward physical forces; a natural bridge is a striking example of the action of blind mechanical forces among the rocks. In the organic world we see living adaptation which involves a non-mechanical principle. An adjustment is an outward fitting together of parts; an adaptation implies something flowing, unstable, plastic, compromising; it is a moulding process; pa.s.sivity on one side, and activity on the other.
Living things struggle; they struggle up as well as down; they struggle all round the circle, while the pull of dead matter is down only.
Behold what a good chemist a plant is! With what skill it a.n.a.lyzes the carbonic acid in the air, retaining the carbon and returning the oxygen to the atmosphere! Then the plant can do what no chemist has yet been able to do; it can manufacture chlorophyll, a substance which is the basis of all life on the globe. Without chlorophyll (the green substance in plants) the solar energy could not be stored up in the vegetable world. Chlorophyll makes the plant, and the plant makes chlorophyll. To ask which is first is to call up the old puzzle, Which is first, the egg, or the hen that laid it?
According to Professor Soddy, the engineer"s unit of power, that of the British cart-horse, has to be multiplied many times in a machine before it can do the work of a horse. He says that a car which two horses used to pull, it now takes twelve or fifteen engine-horse to pull. The machine horse belongs to a different order. He does not respond to the whip; he has no nervous system; he has none of the mysterious reserve power which a machine built up of living cells seems to possess; he is inelastic, non-creative, non-adaptive; he cannot take advantage of the ground; his pull is a dead, unvarying pull. Living energy is elastic, adaptive, self-directive, and suffers little loss through friction, or through imperfect adjustment of the parts. A live body converts its fuel into energy at a low temperature. One of the great problems of the mechanics of the future is to develop electricity or power directly from fuel and thus cut out the enormous loss of eighty or ninety per cent which we now suffer. The growing body does this all the time; life possesses this secret; the solar energy stored up in fuel suffers no loss in being transformed into work by the animal mechanism.
Soddy asks whether or not the minute cells of the body may not have the power of taking advantage of the difference in temperature of the molecules bombarding them, and thus of utilizing energy that is beyond the capacity of the machinery of the motor-car. Man can make no machine that can avail itself of the stores of energy in the uniform temperature of the earth or air or water, or that can draw upon the potential energy of the atoms, but it may be that the living cell can do this, and thus a horse can pull more than a one-horse-power engine. Soddy makes the suggestive inquiry: "If life begins in a single cell, does intelligence?
does the physical distinction between living and dead matter begin in the jostling molecular crowd? Inanimate molecules, in all their movements, obey the law of probability, the law which governs the successive falls of a true die. In the presence of a rudimentary intelligence, do they still follow that law, or do they now obey another law--the law of a die that is loaded?" In a machine the energy of fuel has first to be converted into heat before it is available, but in a living machine the chemical energy of food undergoes direct transformation into work, and the wasteful heat-process is cut off.
VI
Professor Soddy, in discussing the relation of life to energy, does not commit himself to the theory of the vitalistic or non-mechanical origin of life, but makes the significant statement that there is a consensus of opinion that the life processes are not bound by the second law of thermo-dynamics, namely, the law of the non-availability of the energy latent in low temperatures, or in the chaotic movements of molecules everywhere around us. To get energy, one must have a fall or an incline of some sort, as of water from a higher to a lower level, or of temperature from a higher to a lower degree, or of electricity from one condition of high stress to another less so. But the living machine seems able to dispense with this break or incline, or else has the secret of creating one for itself.
In the living body the chemical energy of food is directly transformed into work, without first being converted into heat. Why a horse can do more work than a one-horse-power engine is probably because his living cells can and do draw upon this molecular energy. Molecules of matter outside the living body all obey the law of probability, or the law of chance; but inside the living body they at least seem to obey some other law--the law of design, or of dice that are loaded, as Soddy says. They are more likely always to act in a particular way. Life supplies a directing agency. Soddy asks if the physical distinction between living and dead matter begins in the jostling molecular crowd--begins by the crowd being directed and governed in a particular way. If so, by what?
Ah! that is the question. Science will have none of it, because science would have to go outside of matter for such an agent, and that science cannot do. Such a theory implies intelligence apart from matter, or working in matter. Is that a hard proposition? Intelligence clearly works in our bodies and brains, and in those of all the animals--a controlled and directed activity in matter that seems to be life. The cell which builds up all living bodies behaves not like a machine, but like a living being; its activities, so far as we can judge, are spontaneous, its motions and all its other processes are self-prompted.
But, of course, in it the mechanical, the chemical, and the vital are so blended, so interdependent, that we may never hope to separate them; but without the activity called vital, there would be no cell, and hence no body.
It were unreasonable to expect that scientific a.n.a.lysis should show that the physics and chemistry of a living body differs from that of the non-living. What is new and beyond the reach of science to explain is the _kind of activity_ of these elements. They enter into new compounds; they build up bodies that have new powers and properties; they people the seas and the air and the earth with living creatures, they build the body and brain of man. The secret of the activity in matter that we call vital is certainly beyond the power of science to tell us. It is like expecting that the paint and oil used in a great picture must differ from those in a daub. The great artist mixed his paint with brains, and the universal elements in a living body are mixed with something that science cannot disclose. Organic chemistry does not differ intrinsically from inorganic; the difference between the two lies in the purposive activity of the elements that build up a living body.
Or is life, as a New England college professor claims, "an _x_-ent.i.ty, additional to matter and energy, but of the same cosmic rank as they,"
and "manifesting itself to our senses only through its power to keep a certain quant.i.ty of matter and energy in the continuous orderly ferment we call life"?
I recall that Huxley said that there was a third reality in this universe besides matter and energy, and this third reality was consciousness. But neither the "_x_-ent.i.ty" of Professor Ganong nor the "consciousness" of Huxley can be said to be of the same cosmic rank as matter and energy, because they do not pervade the universe as matter and energy do. These forces abound throughout all s.p.a.ce and endure throughout all time, but life and consciousness are flitting and uncertain phenomena of matter. A p.r.i.c.k of a pin, or a blow from a hammer, may destroy both. Unless we consider them as potential in all matter (and who shall say that they are not?) may we look upon them as of cosmic rank?
It is often urged that it is not the eye that sees, or the brain that thinks, but something in them. But it is something in them that never went into them; it arose in them. It is the living eye and the living brain that do the seeing and the thinking. When the life activity ceases, these organs cease to see and to think. Their activity is kept up by certain physiological processes in the organs of the body, and to ask what keeps up these is like the puppy trying to overtake its own tail, or to run a race with its own shadow.
The brain is not merely the organ of the mind in an external and mechanical sense; it is the mind. When we come to living things, all such a.n.a.logies fail us. Life is not a thing; thought is not a thing; but rather the effect of a certain activity in matter, which mind alone can recognize. When we try to explain or account for that which we are, it is as if a man were trying to lift himself.
Life seems like something apart. It does not seem to be amenable to the law of the correlation and conservation of forces. You cannot transform it into heat or light or electricity. The force which a man extracts from the food he eats while he is writing a poem, or doing any other mental work, seems lost to the universe. The force which the engine, or any machine, uses up, reappears as work done, or as heat or light or some other physical manifestation. But the energy of foodstuffs which a man uses up in a mental effort does not appear again in the circuit of the law of the conservation of energy. A man uses up more energy in his waking moments, though his body be pa.s.sive, than in his sleeping. What we call mental force cannot be accounted for in terms of physical force.
The sun"s energy goes into our bodies through the food we eat, and so runs our mental faculties, but how does it get back again into the physical realm? Science does not know.
It must be some sort of energy that lights the lamps of the firefly and the glow-worm, and it must be some sort or degree of energy that keeps consciousness going. The brain of a Newton, or of a Plato, must make a larger draft on the solar energy latent in food-stuffs than the brain of a day laborer, and his body less. The same amount of food-consumption, or of oxidation, results in physical force in the one case, and mental force in the other, but the mental force escapes the great law of the equivalence of the material forces.
John Fiske solves the problem when he drops his physical science and takes up his philosophy, declaring that the relation of the mind to the body is that of a musician to his instrument, and this is practically the position of Sir Oliver Lodge.
Inheritance and adaptation, says Haeckel, are sufficient to account for all the variety of animal and vegetable forms on the earth. But is there not a previous question? Do we not want inheritance and adaptation accounted for? What mysteries they hold! Does the river-bed account for the river? How can a body adapt itself to its environment unless it possess an inherent, plastic, changing, and adaptive principle? A stone does not adapt itself to its surroundings; its change is external and not internal. There is mechanical adjustment between inert bodies, but there is no adaptation without the push of life. A response to new conditions by change of form implies something actively responsive--something that profits by the change.
VII
If we could tell what determines the division of labor in the hive of bees or a colony of ants, we could tell what determines the division of labor among the cells in the body. A hive of bees and a colony of ants is a unit--a single organism. The spirit of the body, that which regulates all its economies, which directs all its functions, which coordinates its powers, which brings about all its adaptations, which adjusts it to its environment, which sees to its repairs, heals its wounds, meets its demands, provides more force when more is needed, which makes one organ help do the work of another, which wages war on disease germs by specific ferments, which renders us immune to this or that disease; in fact, which carries on all the processes of our physical life without asking leave or seeking counsel of us,--all this is on another plane from the mechanical or chemical--super-mechanical.
The human spirit, the brute spirit, the vegetable spirit--all are mere names to fill a void. The spirit of the oak, the beech, the pine, the palm--how different! how different the plan or idea or interior economies of each, though the chemical and mechanical processes are the same, the same mineral and gaseous elements build them up, the same sun is their architect! But what physical principle can account for the difference between a pine and an oak, or, for that matter, between a man and his dog, or a bird and a fish, or a crow and a lark? What play and action or interaction and reaction of purely chemical and mechanical forces can throw any light on the course evolution has taken in the animal life of the globe--why the camel is the camel, and the horse the horse? or in the development of the nervous system, or the circulatory system, or the digestive system, or of the eye, or of the ear?
A living body is never in a state of chemical repose, but inorganic bodies usually are. Take away the organism and the environment remains essentially the same; take away the environment and the organism changes rapidly and perishes--it goes back to the inorganic. Now, what keeps up the constant interchange--this seesaw? The environment is permanent; the organism is transient. The spray of the falls is permanent; the bow comes and goes. Life struggles to appropriate the environment; a rock, for example, does not, in the same sense, struggle with its surroundings, it weathers pa.s.sively, but a tree struggles with the winds, and to appropriate minerals and water from the soil, and the leaves struggle to store up the sun"s energy. The body struggles to eliminate poisons or to neutralize them; it becomes immune to certain diseases, learns to resist them; the thing is _alive_. Organisms struggle with one another; inert bodies clash and pulverize one another, but do not devour one another.
Life is a struggle between two forces, a force within and a force without, but the force within does all the struggling. The air does not struggle to get into the lungs, nor the lime and iron to get into our blood. The body struggles to digest and a.s.similate the food; the chlorophyll in the leaf struggles to store up the solar energy. The environment is unaware of the organism; the light is indifferent to the sensitized plate of the photographer. Something in the seed we plant avails itself of the heat and the moisture. The relation is not that of a thermometer or hygrometer to the warmth and moisture of the air; it is a vital relation.
Life may be called an aquatic phenomenon, because there can be no life without water. It may be called a thermal phenomenon, because there can be no life below or above a certain degree of temperature. It may be called a chemical phenomenon, because there can be no life without chemical reactions. Yet none of these things define life. We may discuss biological facts in terms of chemistry without throwing any light on the nature of life itself. If we say the particular essence of life is chemical, do we mean any more than that life is inseparable from chemical reactions?
After we have mastered the chemistry of life, laid bare all its processes, named all its transformations and trans.m.u.tations, a.n.a.lyzed the living cell, seen the inorganic pa.s.s into the organic, and beheld chemical reaction, the chief priestess of this hidden rite, we shall have to ask ourselves, Is chemistry the creator of life, or does life create or use chemistry? These "chemical reaction complexes" in living cells, as the biochemists call them, are they the cause of life, or only the effect of life? We shall decide according to our temperaments or our habits of thought.
IX
THE JOURNEYING ATOMS
I
Emerson confessed in his "Journal" that he could not read the physicists; their works did not appeal to him. He was probably repelled by their formulas and their mathematics. But add a touch of chemistry, and he was interested. Chemistry leads up to life. He said he did not think he would feel threatened or insulted if a chemist should take his protoplasm, or mix his hydrogen, oxygen, and carbon, and make an animalcule incontestably swimming and jumping before his eyes. It would be only evidence of a new degree of power over matter which man had attained to. It would all finally redound to the glory of matter itself, which, it appears, "is impregnated with thought and heaven, and is really of G.o.d, and not of the Devil, as we had too hastily believed."
This conception of matter underlies the new materialism of such men as Huxley and Tyndall. But there is much in the new physics apart from its chemical aspects that ought to appeal to the Emersonian type of mind.
Did not Emerson in his first poem, "The Sphinx," sing of
Journeying atoms, Primordial wholes?
In those ever-moving and indivisible atoms he touches the very corner-stone of the modern scientific conception of matter. It is hardly an exaggeration to say that in this conception we are brought into contact with a kind of transcendental physics. A new world for the imagination is open--a world where the laws and necessities of ponderable bodies do not apply. The world of gross matter disappears, and in its place we see matter dematerialized, and escaping from the bondage of the world of tangible bodies; we see a world where friction is abolished, where perpetual motion is no longer impossible; where two bodies may occupy the same s.p.a.ce at the same time; where collisions and disruptions take place without loss of energy; where subtraction often means more--as when the poison of a substance is rendered more virulent by the removal of one or more atoms of one of the elements; and where addition often means less--as when three parts of the gases of oxygen and hydrogen unite and form only two parts of watery vapor; where ma.s.s and form, centre and circ.u.mference, size and structure, exist without any of the qualities ordinarily a.s.sociated with these things through our experience in a three-dimension world. We see, or contemplate, bodies which are indivisible; if we divide them, their nature changes; if we divide a molecule of water, we get atoms of hydrogen and oxygen gas; if we divide a molecule of salt, we get atoms of chlorine gas and atoms of the metal sodium, which means that we have reached a point where matter is no longer divisible in a mechanical sense, but only in a chemical sense; which again means that great and small, place and time, inside and outside, dimensions and spatial relations, have lost their ordinary meanings. Two bodies get inside of each other. To the physicist, heat and motion are one; light is only a mechanical vibration in the ether; sound is only a vibration in the air, which the ear interprets as sound.
The world is as still as death till the living ear comes to receive the vibrations in the air; motion, or the energy which it implies, is the life of the universe.
Physics proves to us the impossibility of perpetual motion among visible, tangible bodies, at the same time that it reveals to us a world where perpetual motion is the rule--the world of molecules and atoms. In the world of gross matter, or of ponderable bodies, perpetual motion is impossible because here it takes energy, or its equivalent, to beget energy. Friction very soon turns the kinetic energy of motion into the potential energy of heat, which quickly disappears in that great sea of energy, the low uniform temperature of the earth. But when we reach the interior world of matter, the world of molecules, atoms, and electrons, we have reached a world where perpetual motion _is_ the rule; we have reached the fountain-head of energy, and the motion of one body is not at the expense of the motion of some other body, but is a part of the spontaneous struggling and jostling and vibration that go on forever in all the matter of the universe. What is called the Brunonian movement (first discovered by the botanist Robert Brown in 1827) is within reach of the eye armed with a high-power microscope. Look into any liquid that holds in suspension very small particles of solid matter, such as dust particles in the air, or the granules of ordinary water-color paints dissolved in water: not a single one of the particles is at rest; they are all mysteriously agitated; they jump hither and thither; it is a wild chaotic whirl and dance of minute particles. Brown at first thought they were alive, but they were only non-living particles dancing to the same tune which probably sets suns and systems whirling in the heavens.
Ramsay says that tobacco smoke confined in the small flat chamber formed in the slide of a microscope, shows this movement, in appearance like the flight of minute b.u.t.terflies. The Brunonian movement is now believed to be due to the bombardment of the particles by the molecules of the liquid or gas in which they are suspended. The smaller the particles, the livelier they are. These particles themselves are made up of a vast number of molecules, among which the same movement or agitation, much more intense, is supposed to be taking place; the atoms which compose the molecules are dancing and frisking about like gnats in the air, and the electrons inside the atoms are still more rapidly changing places.
We meet with the same staggering figures in the science of the infinitely little that we do in the science of the infinitely vast. Thus the physicist deals with a quant.i.ty of matter a million million times smaller than can be detected in the most delicate chemical balance.
Molecules inconceivably small rush about in molecular s.p.a.ce inconceivably small. Ramsay calculates how many collisions the molecules of gas make with other molecules every second, which is four and one half quintillions. This staggers the mind like the tremendous revelations of astronomy. Mathematics has no trouble to compute the figures, but our slow, clumsy minds feel helpless before them. In every drop of water we drink, and in every mouthful of air we breathe, there is a movement and collision of particles so rapid in every second of time that it can only be expressed by four with eighteen naughts. If the movement of these particles were attended by friction, or if the energy of their impact were translated into heat, what hot mouthfuls we should have! But the heat, as well as the particles, is infinitesimal, and is not perceptible.