§ 1. Things and Living Creatures. § 2. The Characteristic Features of the Realm of Organisms. § 3. A Multitude of Individualities, yet a Systema Naturæ. § 4. Abundance and Insurgence of Life. § 5. Struggle and Sifting. § 6. A System of Interrelated Lives. § 7. The Prevalence of Adaptations. § 8. The Pervasiveness of Beauty. § 9. The Other Side of the Picture. § 10. Resemblances between the Realm of Organisms and the Domain of the Inorganic. § 11. Contrasts between the Realm of Organisms and the Domain of the Inorganic. § 12. The Suitability of the Inorganic to be the Basis and Environment of the Organic.
§ 1. Things and Living Creatures.
IN the concrete fulness of the world without, we distinguish by common consent the realm of organisms and the domain of the inorganic. Sun and stars, sky and sea, mountains and rivers, the air we breathe and the dust beneath our feet, crystals and precious stones, it seems like colour-blindness to sum this up in the negative and unattractive term inorganic. But better that than use a question-begging word.
We must not dogmatically say inanimate Nature, for it is making a sweeping assertion to declare that the inorganic cannot have a meta-kinetic aspect. Nor is it quite satisfactory to speak of the mechanical order of things, for we ourselves illustrate mechanical principles, even when we raise our arm or eyebrow in protest. Moreover, it cannot be said that a mechanical summing up of even not-living occurrences is necessarily exhaustive. Nor can we speak with satisfactory precision of the physical order, for living creatures are also physical systems, though more; and the phrase purely physical is again question-begging.
So let us call it allfrom the solar system to the dew-dropthe inorganic domain. We cannot hold it rigidly apart from living organisms, for it is continually undergoing modification at their hands. Parts of it are ever entering into the bodies of organisms, and into its repository the disenchanted dust of life is ever returning. We know the inorganic system of things only in terms of mind, and our first adventure of scientific faith is to believe in its external reality; yet it looms impressively over usa great dumb giant, holding us, even in our defiance, in its grip and bearing us with it on its stupendous journeying through space.
§ 2. The Characteristic Features of the Realm of Organisms.
Let us begin with an impressionist survey of the realm of organisms, and afterwards contrast this with a general view of the inorganic domain. It is surely a magnificent spectacle that the obviously animate presents. What a gamut of life from the microscopic Infusorian to the giant whale, from the hyssop on the wall to the cedar of Lebanon! What abundance of life is revealed when the dredge comes up, or when the insects rise before us in a cloud as we walk through the grassland of a warm country. What variety of architecture, what abundance of individuality within the same style! All is suggestive of fertile imagination. How strong the pressure, as the waves of life surge up against their shores; how numberless the hand-and-glove fitnesses; how subtle the linkages; how constant the changefulness; how universal the beauty! But let us be more analytic and illustrate in due order the deeper impressions which fill the mind after the crowd of details sinks to rest, for these must form part of the materials which Biology gives over to philosophy to build with.
§ 3. A Multitude of Individualities, yet a Systema Naturæ.
When we look at Nature with a fresh eye, in a new country, or in some novel experience such as dredging, we have a transient impression of overwhelming confusion, as if Aladdin's cave had been suddenly burst open before us. Many miss this in ordinary circumstances because familiarity breeds the contempt of inattention, and also because a very large number of living creatures are cryptozoic. For every conspicuous plant there are often a score inconspicuous, and for every readily visible animal there must be a hundred unseen. It is not of individuals that we are thinking, but of individualities, of species. There are at least 25,000 named backboned animals, ten times as many named back-boneless animals, and about as many plants. There are about 100,000 Dicotyledonous Flowering Plants. Darwin speaks of finding twenty different kinds of flowering plants on a patch of turf four feet by three, and there may be as many different kinds of animals on one stone brought up from the sea-floor.
The study of marine animals has been enthusiastic and intense for many years, but those who know most about it will agree with what the poet Spenser said long ago:
But what an endlesse worke have I in hand,
To count the seas abundant progeny,
Whose fruitful seede farre passeth those on land,
And also those which wonne in th' azure sky;
For much more eath, to tell the starres on hy,
Albe they endlesse seem in estimation,
Than to recount the seas posterity;
So fertile be the floods in generation,
So huge their numbers, and so numberlesse their nation.
We shall come later on to the difficult problem of individuality or species; but our view of Nature as a whole must take account of the fact that species are multitudinous and that they represent discontinuous individualities, with much more constancy than the earlier Darwinians supposed. Linnæus said: There are as many species as there were ideas in the Divine Mind, and there is no doubt that a good species is like a clear-cut idea. At the other extreme of comparison, it is like a chemical element, but on a higher plane. As Goethe said, The one thing Nature seems to aim at is Individuality; yet she cares nothing for individuals. If we personify Animate Nature, it must at least be as an artist with inexhaustible imaginative resources, with extraordinary mastery of materials.
But in the prodigal wealth of individuality, it is not a dæmonic confusion, but a rational order that we see. The species are remarkably unique and discontinuous, each with a character of its own, yet they are often like stages in individual development, and they can often be classified in a logical series. Linnæus established his Systema Naturæ quite apart from any evolutionist conception, and though the fact of genetic relationship lies behind every so-called natural classification, our present point is simply that Each of her works has an essence of its own; each of her phenomena a special characterisation; and yet their diversity is in unity.
§ 4. Abundance and Insurgence of Life.
A second impression is that of wealth of numbers and of indomitable will to live. There are, indeed, organisms which multiply slowly, such as elephants, golden eagles, and century plants, but this is not the way with the majority. Most of the streams of life are ever tending to overflow their banks. Even the rarities may do so in appropriate conditions; thus a rather rare wingless Glacier-Insect was recently found on one stretch of the mer-de-glace at Chamonix in numbers almost equal to the population of Great Britain and Ireland. In the case of organisms of low individuation, which hold their own rather because they are many than because they are strong or wise, the productivity is beyond all our powers of conception. From one Infusorian there may be a million by the end of a week, and in some of the floating meadows of the sea there may be a quarter of a million units in a gallon of water.
There is a well-known British starfish, Luidia ciliaris, which produces at least two hundred millions of eggs, and yet it is not what one would call a common animal.
We are familiar with calculations of what would occur if there were no thinning of the cropshow soon the earth would be covered with a weed, or the sea filled solid with a fish, or the sky darkened with an insect, and recurrent plagues of locusts, sparrows, rabbits, and moles remind us that a possibility may easily become an actuality. After allowing a prodigious mortality of 95 per cent., it is computed that the 10,000,000 pairs of breeding rats in Britain on New Year's Day, 1918, were represented by 40,000,000 pairs at the end of the year, and by 12,000,000 more pairs the following month! There is a grimness in the well-known remarks of Linnæus that three flies will consume the car case of a horse as quickly as a lion can. Professor Woodruff observed the successive asexual generations of the common slipper-animalcule (Paramecium) for five years between 1907 and 1912 and found that there were 3,029 of themover three every forty-eight hours. Careful calculation showed that they had given evidence of the capacity of producing in the five years a volume of protoplasm approximately equal to 10,000 times the volume of the earth. This power of self-increase must be taken account of in our conception of living organisms, and the resulting abundance of life must form part of our impressionist picture of Animal Nature. At the autumnal climax of productivity in lakes, there may be to the square yard 7,000 millions of a well-known Diatom, Melosira varians, so that the water is like a living soup.
We have to remember, moreover, the obvious but notable fact that we are dealing not with items like grains of sand, but with individuals, each itself and no other. Mendel put an end to the phrase as like as two peas.
Individual organisms differ greatly in degree of complexity and of integration. Many an Infusorian has an intricate organisation and lives a by no means monotonous life, though it is only what we somewhat fallaciously call a single cell. Hardly any larger than some Infusorians are some of the Rotifers, sometimes with about 1,000 cells; a minnow has its millions, and a bird its millions of millions. What a contrast between the very incipient integration of a sponge, the intricate division of labour in a Portuguese Man of War hesitating between colony and individual, and the compact co-ordination of the circumspect wren. As a recent student of the subject, Mr. Julian S. Huxley (1912), puts it, we are confronted in Nature with closed independent systems with harmonious parts and with capacity for continuance. Such are individuals. Though the closure is never complete, the independence never absolute, the harmony never perfect, yet systems and tendency alike have real existence. The individual is Unity in Diversityin what it is and in what it does,a whole whose diverse parts all work together, ensuring continuance. When it transcends the limits of its substance, Mr. Huxley says, that is personality.
But in addition to the abundance of lifealike of individualities and of individualsthere is the quality of insurgence. Living creatures press up against all barriers; they fill every possible niche all the world over; they show that Nature abhors a vacuum. We find animals among the snow on Monte Rosa at a height of over 10,000 feet; we dredge them from the floor of the sea, from those great deeps of over six miles where Mount Everest would be much more than engulfed. It is hard to say what difficulties living creatures may not conquer or circumvent. You may find insects in hot springs in which you cannot keep your hand immersed, or Rotifers and other small fry under fifteen feet of ice in the little lakes of Antarctica; you find a Brine-Shrimp and two or three other animals in the Great Salt Lake; you find a fish climbing a tree, and thoroughly terrestrial types like spiders with species living under water; there is, as Dr. Shipley has shown, a bustle of life on the dry twigs of the heather. When we consider the filling of every niche, the finding of homes in extraordinary places, the mastery of difficult conditions, the plasticity that adjusts to out-of-the-way exigencies, the circumvention of space (as in migration) and the conquest of time (as in hibernation), we begin to get an impression of the insurgence of life. We see life persistent and intrusivespreading everywhere, insinuating itself, adapting itself, resisting everything, defying everything, surviving everything!
The great Sequoia trees may be taken as emblems of life's tenacity. For they have been known to flourish over two thousand years. One of the oldest had 2,425 annual rings when it was killed, and must have begun to live 525 years before the Christian era. We have, wrote Prof. W. R. Dudley, deep in their annual rings, records which extend far beyond the beginnings of Anglo-Saxon peoples, beyond even the earliest struggles for liberty and democracy among the Greeksrecords of forest conflagrations, of the vicissitudes of the seasons, of periods of drought and periods of abundant and favouring rains. In our conception of life we must not forget these sublime instances of its power to endure.
§ 5. Struggle and Sifting.
By the insurgence of life we mean a certain quality of push or aggressiveness often observable both in plants and animals. It is an outcome of a native self-assertiveness, and it is a factor in the struggle for existence as much as a consequence of it. More metaphorically, it is an expression of the will to live, or of the spirit of adventure. To the conception of the struggle for existence we shall have to give careful consideration at a later stage; meanwhile we must notice that the phrase leads us astray if it is taken literally or woodenly. It includes every form of the clash between individuals and their environing difficulties, all the novel responses that individual living creatures are always making to the pressure of limiting conditions. These responses may take the form of intensified competition, even of intensified cannibalism; but they have often taken the form, as Darwin emphasised, of some experiment in co-operation, and socialisation, of some new departure which gives the next generation a better start in life. All theory apart, our picture of animate nature is fundamentally out of perspective unless we recognise that a large proportion of the time and energy of living creatures, whether in the fighting line or safe for the time being in organised entrenchments, is devoted to securing not self-preservation, but the welfare of the race. Nature, as Goethe said, is continually taking advantage of her children's capacity for self-forgetfulness.
Whenever the circumstances are critical, and there is inequality or diversity in the response that living creatures make to their environing difficulties and limitations, a process of sifting begins to work, the process of discriminate elimination familiarly known as Natural Selection. This also will engage our attention later, but in the meantime let us not assume that the conventional statement of the process tells us the whole truth. Just as the struggle for existence is often more accurately described as an endeavour after well-being, so, in thinking of Nature's sifting, we go astray if we think of it as at all haphazard (that is a contradiction, in terms), or as directed only to self-preservation, or as being necessarily sanguinary, or as a process in which organisms simply remain like passive branches for the pruning-shears. As a sagacious naturalist has well observed, though somewhat too paradoxically, it is not so much that Nature selects the organisms fittest to her; it is rather that each organism selects the natural conditions fittest to itself.
§ 6. A System of Inter-related Lives.
The hosts of living organisms are not random creatures, they can be classified in battalions and regiments. Neither are they isolated creatures, for every thread of life is inter-twined with others in a complex web. This is one of the fundamental biological conceptsthe correlation of organisms in the web of lifeand it is as characteristically Darwinian as the struggle for existence. No creature lives or dies to itself; there is no insulation. Long nutritive chains often bind a series of organisms together in the very fundamental relation that one kind eats the other. All things are in flux, there is a ceaseless circulation of matter; all flesh is grass and all fish is diatom; and so the stuff of the world goes round from one incarnation to another. One organism gets linked on to others, and becomes dependent on them for the continuance of its race. Flowers and insects are fitted to one another as hand to glove. Cats have to do with the plague in India as well as with the clover, crop at home. The young of the fresh-water mussels are carried about for a time by minnows, and the young of the fish called the bitterling are harboured within the fresh-water mussel. Squirrels affect the cornfields and water wagtails the sheep-folds. In short, we get a glimpse of Nature as a vast system of inter-linked livesa Systema Naturæ in a new sensea web with a pattern (see Thomson, 1914, 1916). With out entering upon any discussion of the weaving or evolution of the web through untold ages, let us take the realm of organisms as it is, and emphasise the fact that just as there is a correlation of organs in the body, so there is a correlation of organisms in the world of life. When we learn something of the intricate give and take, supply and demand, action and reaction between plants and animals, between flowers and insects, between herbivores and carnivores, and between other conflicting yet correlated interests, we begin to get a glimpse of a vast self-regulating organisation. There may be local and temporary friction and disorder; there is the clash of fierce competition in some forms of the struggle for existence; but the larger fact is the smooth working of a balanced correlated system.
In philosophical reconstruction we must surely take account of this inter-relatedness of organisms. Is it not of interest to find in Animate Nature, as in mankind, advance from comparatively isolated units towards systematisation and solidarity? The multitudinous unique threads of life become more and more interwoven; the warp and the woof of the web are hunger and love; we get glimpses of a changing pattern becoming ever finer. The web seems to become increasingly coherent, though man often rends the fabric ruthlessly.
Another point of importance, demanding subsequent study, is that the intricacy of the web of life becomes in itself of great significance in evolution. It is its subtlety that gives point and possibility of survival to minute variations. The very fact of complex interaction and systematisation tends to diminish fortuity and to make towards definite progression. The correlation of organisms which is a product of evolution becomes in turn a directive factor.
§ 7. The Prevalence of Adaptations.
The balance demonstrable on a large scale holds throughout; every higher organism is a complex bundle of adaptations. It is suited to its surroundings, to its food, to its own weight, to its way of moving, to the regularly recurrent exigencies of the seasons, and to recurrent risks of injury. It may be subtly adapted to its mate, in exquisite symbiosis to its offspring, to its ante-natal life, and to dying at the proper time! Wherever you tap organic Nature, Romanes said, it seems to flow with purpose. The theory of this will be discussed later on, but in the meantime without pressing the word purposelet us emphasise the fact that almost all living creatures are definitely and detailedly fit for the particular conditions of their life. There can be no doubt that we live in a world of fitnesses, that we need to search to find misfits. When we think we have found them, we have generally made a mistake. This adaptiveness is another large fact of life, which, whatever be the scientific theory of it, must be incorporated in a concrete Philosophy of Nature. Let us take a few illustrations.
The structure of a long bone in a mammal is architecturally adapted to give the utmost firmness with the minimum expenditure of material; the pollen-basket on the hind-legs of worker-bees is adapted in detail to carrying the nutritive pollen, the golden, or otherwise coloured, germinal dust; the leaf of the Venus fly-trap or of the sundew is adapted with no little subtlety to catching insects; the parts of flowers are often adapted to attract insect-visitors and to make the most of them when they come; the colours and patterns of leaf-insects are adapted to harmonise with the foliage on which they settle; the heart of the ptarmigan is adapted to the strain of high altitudes, and the shoes which the ruffed grouse puts on in winter are adapted for treading on the lightly compacted snow; the mongoose is chemically adapted to resist snake poison; the tendrils of the mermaid's purse are non-living products of the living skate physically adapted to fasten the egg to seaweed; the flatfish is adapted to put on a garment of invisibility against certain backgrounds; the hedgehog is adapted to meet the winter by hibernation; the peacock is adapted to captivate the peahen; the mother mammal is delicately adapted for the prolonged ante-natal life of the offspring; and the so-called egg-tooth at the end of a young bird's bill is adapted to the single operation of breaking the egg-shelland so on throughout the whole animal kingdom, for the point of this random list is but to remind us that (with a few very interesting exceptions) every detail of structure and function may be regarded as adaptive. As the late Professor Weismann used to say, When you take away all the adaptations from a whale, there is not much left. To illustrate subtlety, however, let us pause for a moment over a particular case.
The illustration we select concerns the parental care in a remarkable New Guinea fish called Kurtus. Each egg has an envelope of over a hundred twisted threads, coiled like the rubber filaments in a cored golf-ball. When the eggs are laid the filaments unwind automatically and unite in strings, which combine into a cylindrical cord. Thus the eggs are bound together, forming a twin cluster like a double bunch of onions such as we see the Breton boys carrying in the streets. But what is the bunch to be fastened to? The answer is almost incredible. At the breeding season, Prof. Max Weber tells us, a bony process on the top of the skull of the male fish grows forwards and downwards like a bent little finger, and forms eventually a ring or eye. But before the hook becomes an eye the cord of the double bunch of eggs is somehow passed into the loop and attached, and the male fish goes about with his prospective family fastened to the top of his head. The female shows no trace of the hooked process of bone, so that we have an interesting, almost startling coincidence, of an adaptation which makes the eggs into a double bunch and an adaptation which fixes them to the male's head.
This is but a striking instance of what obtains throughout Animate NatureAdaptation upon Adaptation. And, as we shall afterwards see, the working out of a more or less adequate Natural Selection account of how these adaptations have come to be does not lessen the wonder of the variability that supplies the raw material, or the hereditary relation which conserves each gain. The magicalness has gone; the rationality shines out more brightly than ever.
§ 8. The Pervasiveness of Beauty.
Another undeniable impression is that there is beauty everywhere. Apart from disease, which is almost unknown in wild Nature, apart from unfinished organisms which Nature hides awayoften so carefully, apart from various domesticated animals and cultivated plants which bear too flagrantly the marks of man's artistically clumsy, though scientifically clever, fingers, all organisms are artistic harmonies, pleasing to the unprejudiced eye, evoking the æsthetic emotion, especially when seen in their natural setting. And not only the organisms themselves, but the works of their hands are beautifulthe nest, and the web, and the honeycomb, and the coral reef, and the bower-bird's bower. Nature has given her verdict in favour of beautythe reward of survival.
§ 9. The Other Side of the Picture.
It may be said, perhaps, that we have given a one-sided picturethat Animate Nature is a vast gladiatorial show reeking with blood, that every hedgerow is crowded with cruelty, that parasitism is rife, that there is much ugliness and devilry, that the exuberant abundance of life is shadowed by the obtrusive abundance of death, and that there are numerous dis-harmonies or imperfect adaptations. Throughout the organic world, Professor Hobhouse says, harmony is shot through with discord. It would be utterly unscientific to disregard these shadows, and we shall consider them at later stages in our argument Anticipating that discussion, we venture to say that many of the shadows are of man's making, that many are due to misunderstanding, and that those that are real do not seriously affect the general truth of our impressionist picture of Animate Nature, of which the prominent features are:the multitude of individualities in an orderly Systema Naturæ; the abundance and insurgence of life; the ceaseless struggle and endeavour, which makes for self-preservation, self-assertion, and self-realisation, but also for the welfare of the race; the sifting and singling that works towards both these ends; the extent to which every creature is a bundle of adaptations; and the beauty that is everywhere.
§ 10. Resemblances between the Realm of Organisms and the Domain of the Inorganic.
With our impressionist picture of the realm of organisms clearly in view, let us now briefly compare it with what is true of the domain of the organic. We must avoid two extremes. On the one hand, there is the error of exaggerating the differences so that an impression of utter discontinuity is created. This is undoubtedly false, for organisms have, as material systems, an inorganic aspect. On the other hand, there is the error of exaggerating the resemblances, so that we lose hold of what is distinctive in each. Let us first notice some of the resemblances.
As among plants and animals, so among lifeless things there is extraordinary heterogeneity. There are over eighty different kinds of elements; the number of different minerals is legion; the multitude of the stars is untold. But, just as there is in the realm of organisms the common denominator protoplasm (or shall we say animate protoplasm?), so there is in the inorganic domain an abstract common denominator with a few terms, such as matter in motion and ether under strain, which are not reducible to anything simpler. The living and the not-living worlds agree in showing diversity in unity, and the big generalisations of Biology such as omne vivum e vivo, the hereditary relation, the persistence of the organism in spite of ceaseless change, and so on, may be compared to the great chemico-physical generalisations of the persistence of mass, of momentum, of energy.
What the physical irreducibles are is a question beyond our scope, all that we require for our argument is the agreement among physicists that there are but a few fundamental concepts. Thus Sir Oliver Lodge declared in 1913: Matter in motion, Ether under strain, constitute the fundamental concrete things we have to do with in physics. The first pair represent kinetic energy; the second, potential energy; and all the activities of the material universe are represented by alternations from one of these forms to the other (1913, p. 35). In terms of a few fundamental concepts, then, it is possible to formulate a very large part at any rate of what is observed in the inorganic domain. Whether they exhaust the reality of that domain is quite another question.
In both worlds we get the impression of order and uniformity. We recognise it, for instance, in the frequent inexorableness of the hereditary relation between successive generations; we are even more familiar with it in the domain of the inorganic. There do not seem to be many big collisions in the heavens. Everything works so steadily that the return of a comet can be predicted to a night, and the occurrence of an eclipse to an hour. The weather may be changeable, but no one supposes that it is disorderly. It is not a multiverse that we live in, but a cosmos. In his famous Discourse on Molecules (1873), Clerk-Maxwell spoke of the verification of the postulate of stability in the properties of things. Unthinkably distant worlds are built up of molecules of the same kind as those which we find on the earth. A molecule of hydrogen, for instance, whether in our laboratories, or in Sirius or in Arcturus, executes its vibrations in precisely the same time. The furniture of the earth and of the heavens may be changed, but the properties of its constituents remain. Though in the course of ages catastrophes have occurred and may yet occur in the heavens, though ancient systems may be dissolved and new systems evolved out of their ruins, the molecules out of which these systems are builtthe foundation-stones of the material universeremain unbroken and unworn. They continue this day as they were createdperfect in number and measure and weight. For molecules a modern chemist would read atoms, and even then he would remind us of the apparent disintegration of the atom in radio-active substances. But in the main what Clerk-Maxwell said remains true. It is evident that the fulcrum of the inorganic on which organisms rest their lever is one of reliable steadiness.
Another point of resemblance or analogy is that the eighty or so elements may well be compared to species, or better to types of organisms. We do not know very well what being an element means, and we do not know very well what being a species means, but we do know that in elements and species alike we have to do with uniqueness or specificity. One is not forgetting, of course, what has been done in the way of experimental transformism alike with organic species and chemical elements, but, taking the world as it is, the characteristic feature, whether of species or elements, is the persistence of each clear-cut entity on its own line of being.
As to the inter-relatedness in the realm of organisms, it has its analogue in any systematisation that there is in the inorganic domain. The approximation to individuality illustrated in the earth or in the solar system is associated with a certain amount of correlation between its parts. The circulation of matter in the organic realm has its counter-part in the inorganic. The persistence of matter and the conservation of energy hold true, so far as we know, in both.
As regards beauty, it varies greatly in significance, but there is no limit to its range. In its way the grain of sand is as perfect as the egg of the wren. There is often an indescribably fine finish about the inorganic natural product, as we see in agates and crystals, and there is a haunting beauty in things great and small, in the mountain and in the pebble, that makes us thoughtful as well as joyous. We venture to say, however, that in the inorganic domain combinations of lines and colours that are not beautiful are not uncommon, whereas in the organic realm the non-beautiful is extremely rare, the reason being that beauty is correlated with individuality.
If we assume the external independence of what we call matter and regard it as the building-stone of the world, those of us who are not chemists and physicists must make an effort to rid ourselves of any picture of it as gross and inert. How much matter is invisible like the air! How much is transparent like the water! How tenuous is the film of the soap-bubble! How much is ever passing from phase to phase like an elusive genie! Those who are inclined to think meanly of matter should look again at its magnificence in the starry heavens and at its exquisiteness in the miniature architecture of snow-crystals. We must also bear in mind how finely it lends itself to Life's purposesthe fashioning of a feather, the sculpturing of a shell, the casting within the bud of those blue bells which ring every day by the wayside.
But when we pass from ordinary sight to scientific vision, how subtle and ethereal matter becomes! What pictures modern physics gives us of a restless activity suggestive of life!
Matter is thought of as consisting of unit particles or molecules, which move freely with great velocity in gases, and these molecules are thought of as consisting of several atoms which exist in specific and constant configurations. Until 1896 atoms were regarded as the ultimate building-stones of the material universe, but it has since been suggested that an integration of hundreds of thousands of electrons might form an atom or form a revolving halo around an atom. The study of radium has led to the view that the atom is not the natural limit of the subdivision of matter, that the stream of energy poured forth by radium is due to a transmutation of the position of parts constituting the atom,the radium slowly changing into something elsehelium, and eventually lead.
The individual molecules of matter in a gaseous state are believed to move with great velocity, incessantly colliding with one another and rebounding, making impacts on the walls of the vessel that contains them, or spreading themselves through any space to which there is free access. We need not try to follow what is beyond our personal scope, but to illustrate the subtlety of modern conceptions of matterwhich is all that concerns us at presentlet us take a few sentences from Professor Soddy's luminous Matter and Energy:
Every cubic centimetre of any gas, measured under standard conditions (0° C. and 760 millimetres barometric pressure), contains twenty-seven million million million molecules. The weight of the single molecule of hydrogen is about three million-million-million-millionths of a gram, and its velocity at 0° C. is rather more than a mile a second. The hydrogen molecule is, it is true, the smallest and simplest molecule of matter known, but it is a large and sluggishly moving individual compared with another known particle, the electron or atom of negative electricity (Matter and Energy, p. 82).
When the temperature of a gas is lowered the molecules come nearer one another, till their mutual tendency to draw together restricts their wandering movements, and a liquid is formed. Inside the surface skin of the liquid the molecules move very rapidly, and collide so frequently that they follow very zigzag paths, being perpetually turned back the way they came. It is no dance of molecules, but a chaotic jostling. Every drop of liquid is in a state of commotion and turmoil indescribable (ibid., p. 89). Of solids relatively little is known, but in a crystalline solid where we have to deal with fixed architecture there can be no translatory motion. But vibratory motion in constrained paths there must be among the molecules of a solid, increasing with the temperature until the molecules drag their anchors, as it were, and the substance melts (ibid., p. 94).
Thus the concept of matter leads us to a very ethereal picture. What is to be said of energy? It is the power of doing work, and may be actual or potential, in motion or in position. But except when it changes, its existence can only he inferred. Professor Soddy writes: The Apostle Paul had no thought of physical things in his mind when he used the words, The things which are seen are temporal, but the things which are not seen are eternal. But the words can be applied with profit to illustrate, perhaps more forcibly than any other single sentence, the essential nature of energy. It is only the temporary changes in the form and relative amount of energy which are manifest. So long as energy neither changes in amount nor in position, it belongs to the unseen and eternal. No direct evidence of its existence can be obtained. Yet we are never in doubt as to its reality, for it is always conserved. And besides Matter and Energy there is the Ether which Sir Oliver Lodge describes as the universal connecting medium which binds the universe together, and makes it a coherent whole instead of a chaotic collection of independent isolated fragments. It is the vehicle of transmission of all manner of force, from gravitation down to cohesion and chemical affinity; it is therefore the storehouse of potential energy. It does not move in the sense of locomotion, though it is probably in a violent state of rotational or turbulent motion in its smallest parts; and to that motion its exceeding rigidity is due. Its density must be far greater than that of any form of matter, yet matter moves through it with perfect freedom, without any friction or viscosity (1913, p. 33).
The ether, says Sir J. J. Thomson, is not a fantastic creation of the speculative philosopher; it is as essential to us as the air we breathe. The study of this all-pervading substance is perhaps the most fascinating and important duty of the physicist. And Sir Oliver Lodge also speaks of the fascination of this portentous entity, material but no matter, the great engine of continuity:Its curiously elusive and intangible character, combined with its universal and unifying permeance, its apparently infinite extent, its definite and perfect properties, make the ether the most fundamental ingredient in the material cosmos.
We have delayed over these elementary ideas because those who are convinced of the apartness of living creatures are apt to fail in appreciation of the inorganic domain. Even the use of the word inert betrays either prejudice or ignorance, both probably unconscious.
Professor Enriques rightly objects to the false antithesis involved in opposing the spontaneity and change of everything that lives to the inertia and immutability of matter. He uses spontaneity here to mean activity or possibility of changing through internal conditions, and rejects the idea of an absolutely passive matter. The view seems far more adequate, he says, which holds that everything around us is living and active, save for a difference in degree in the intensity or in the rapidity of the changes, and in the relative importance of the internal and external factors for the course of the phenomena (Enriques, 1914, p. 368). It is useful, however, to keep a term like living for organisms only.
§ 11. Contrasts between the Realm of Organisms and the Domain of the Inorganic.
Let us turn from the resemblances to the contrasts between the realm of organisms and the domain of the inorganic.
The first great contrast is that there are no true individuals in the domain of the inorganic, though there is a great diversity of quality. A crystal approaches some of the criteria of being an individualit has definiteness of form, coherence, a capacity for a sort of growth and repair; but a crystal is homogeneous, not made up of inter-dependent parts working together to secure continuance either of itself or of its kind. The crystal's regularity is not functional; it is perhaps the visible expression of the molecular structure. Similarly, the solar system makes some approach to being an individual, having independence and unity in diversity, but it can hardly be said that the solar system is an agent, or that its working is directed towards its own continuance.
There are few phenomena in the domain of the inorganic which can be spoken of as propagative, though one may think of the origin of a double star, or of the earth giving birth to the moon, or of the multiplication of crystals. This is in marked contrast with the abundant multiplication characteristic of organisms.
And while the volcano is insurgent enough in a sense, and the breakers seem furious in their assaults on the cliffs, we know that there is no freedom of action, that everything is without alternative.
There seems no doubt as to the general fact that the solar system developed from a much less differentiated, much more diffuse, condition; it is certain, that our earth has passed through various stages of development, and has become increasingly differentiated in its pattern and features; and many facts point to the occasional origin, of new chemical collocations in Nature; but there is nothing in the domain of the inorganic which can be compared with any precision to organic evolution and there is nothing that can be compared to the struggle for existence. We are not justified in saying that there may not have been elimination of unstable collocations which could not last and had to be scrapped, but this bears at most a superficial resemblance to the answering back to environing limitations and difficulties which is the essential feature of the organismal struggle for existence. There is neither endeavour nor selection in the inorganic domain, and till organisms emerged there was little or no power of learning in the school of time.
For plain people it was a very useful classification that Samuel Butler suggested: Living Creatures, Machines, and Things-in-General. Machines are inorganic material systems, but they must be kept quite by themselves in any discussion like this, for they are collocations put together by man with a definite intention. They are purposive constructions, and they are the only non-living things of which this can be said. A river often cuts its way very effectively, but we are romancing if we speak of its purpose. Its bed is not adapted to it, as a flower to its insect visitor. The concepts of adaptation and purposiveness do not apply in the inorganic world, where there are no alternatives.
It seems that the domain of the inorganic is contrasted with the realm of organisms by the absence of individuality, reproductivity, freedom of action, endeavour, and purposiveness. It is a domain of mechanically necessitated sequences without alternatives and of uniformities without exceptions. In all probability this quality of uniformity has been a quite indispensable basis for the super-structure of life, affording stability for the experiments and endeavours that, have doubtless been characteristic of organisms from the first.
§ 12. The Suitability of the Inorganic to be the Basis and Environment of the Organic.
We wish in conclusion to allude to the very interesting factwhich will demand further attention later onthat the not-living earth exhibits many remarkable fitnesses to be the home of life. Living means trafficking with the environment; to do this effectively organisms must be complex and yet coherent, plastic and yet durable, and they were able to gain these qualities because of the fundamental properties of the primary constituents of the inanimate environment. The properties of Water and Carbon dioxide, the tendency some forms of matter have to complexify, the properties of the colloid state, the character of the sea as a medium, these and other inorganic data are, as Prof. L. J. Henderson (1913, 1917) has shown in detail, extraordinarily well suited to be pre-conditions of organisms. We must, of course, avoid arguing in a circle, for that the earth should be friendly to living creatures is not surprising, since in their physical nature they are bone of her bone and flesh of her fleshher very children. Yet when we give full consideration to the fact that living creatures as material systems are in no wise foreign to the earth, but are in deep and subtle ways congruent and solidary with it, perhaps we shall not be inclined to brush aside hurriedly the suggestion that the domain of the inorganic is as it is for a purpose. At present we leave this as a pious anticipation.
The world without is conveniently divided into the realm of organisms and the domain of the inorganic, which stand in close inter-relation and sharp contrast. In the domain of the inorganicfrom solar system to snow crystal, from the hills and the sea to dust and dew-dropswe are impressedby (a) the rich concrete fulness of different kinds of things and events, which, nevertheless, can be summed up, for most purposes, in terms of a few fundamental concepts, such as matter and motion; (b) the orderly uniformity that pervades it; and (c) the restless and subtle activity that appears to obtain throughout.
A study of the realm of organisms discloses a multitude of individualities and yet an orderly systema naturæ. There is an embarrassment of different kinds25,000 named Vertebrates, ten times as many named backboneless animals, and about as many plants, yet a rational classification is possible.
A second impression is of the abundance and insurgence of life. Most of its streams tend to overflow their banks. Many species are represented by numberless individuals. There is also the quality of insurgence, for we see life intrusive everywhere, pressing up against limitations, circumventing or overcoming difficultieslike a strong will.
Another impression is of ceaseless struggle and endeavour on the one hand, ceaseless selection or sifting on the other. Living creatures react in manifold ways to environing limitations and difficulties, and in the clash that ensues there is often discriminate elimination.
The inter-relatedness of organisms is another fundamental fact. Animate nature is a vast system of interlinked lives, a web with a pattern. As in mankind, there is progress towards systematisation and solidarity, and the correlation of organisms which is a product of evolution becomes in turn a directive factor.
Another fundamental impression is that of fitnesses. Every higher organism is a complex bundle of adaptations. It is suited to its inanimate surroundings, to its food, it may be to other creatures, to its own weight, to its movements; it may be to a mate and to offspring; to regularly recurrent times and seasons and risks of injury; to its ante-natal life and to dying at the proper time!
If we are to consider Animate Nature in its totality we must not overlook the practically universal pervasiveness of beauty of form and colour.
It may be said that this impressionist picture of Animate Nature is one-sided, that it ignores the redness of tooth and claw, the cruelty, the ugliness, the parasitism, the obtrusively enormous mortality, and the mis-adaptations. Much of this objection is due to misunderstanding; the admittedly great difficulties that remain will be discussed in Lecture XVIII.
Comparing the realm of organisms with the domain of the inorganic, we must avoid the error of exaggerating the differences (so that an impression of discontinuity is created) and the error of merging the two (thus missing what is distinctive in each). In the domain of the inorganic there is little individuality (though much difference of quality), no apparent freedom of action, no endeavour, no purposiveness, no learning in the school of time. But its uniformity has been a probably indispensable fulcrum for the lever of will. It should be noted too that the old view of inert matter has given place to a dynamic conception of extraordinary subtlety.