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I PROGRESS, BIOLOGICAL AND OTHER 3

II BIOLOGY AND SOCIOLOGY 69

V PHILOSOPHIC ANTS: A BIOLOGIC FANTASY 177

VI RATIONALISM AND THE IDEA OF GOD 207

PROGRESS, BIOLOGICAL AND OTHER

EVOLUTION: AT THE MIND'S CINEMA

I turn the handle and the story starts: Reel after reel is all astronomy, Till life, enkindled in a niche of sky, Leaps on the stage to play a million parts.

Life leaves the slime and through all ocean darts; She conquers earth, and raises wings to fly; Then spirit blooms, and learns how not to die,-- Nesting beyond the grave in others' hearts.

--I turn the handle: other men like me Have made the film: and now I sit and look In quiet, privileged like Divinity To read the roaring world as in a book. If this thy past, where shall thy future climb, O Spirit, built of Elements and Time!

PROGRESS, BIOLOGICAL AND OTHER

"Usus et impigrae simul experientia mentis Paulatim docuit pedetemtim progredientes." --LUCRETIUS.

"As natural selection works solely by and for the good of each being, all corporeal and mental environments will tend to progress towards perfection." --CHARLES DARWIN.

"Social progress means the checking of the cosmic process at every step and the substitution for it of another which may be called the ethical process." --T. H. HUXLEY.

"It is probable that what hindered Kant from broaching his theory of progress with as much confidence as Condorcet was his perception that nothing could be decisively affirmed about the course of civilization until the laws of its movement had been discovered. He saw that this was a matter for future scientific investigation." --J. B. BURY.

What is the most fundamental need of man? It would be interesting to conduct a plebiscite of such a question, a plebiscite of the same sort that was conducted by one of the French newspapers some years ago, to discover the opinions of its readers as to who was the greatest Frenchman of the century.

That need has been felt by all those to whom life has been more than a problem of the unreflective satisfaction of instincts and desires--however pure those instincts, or beautiful those desires; it has been felt by all in whom the problem of existence has been apprehended by intellect and disinterested imagination.

I say all. There may be rare creatures who, secure in strength of body and mind and in unhampered unfolding of their faculties, possess a confidence by which this need is never felt. They are like those whom Wordsworth drew for us in the "Ode to Duty":--

"There are who ask not if thine eye Be on them; who, in love and truth, Where no misgiving is, rely Upon the genial sense of youth: Glad hearts! without reproach or blot; Who do thy work and know it not."

But such are rare; or should we say that their type of mind, though not uncommon in the earlier years of life, only by the rarest chance achieves its course without a descent into that vale where the finite human intellect grapples unequally with infinite problems?

The need has been felt in all ages and in all countries; and the answers, the partial satisfactions of the needs which have been found by the mind of men, are correspondingly diverse.

Savages have endowed the objects around them, living and inanimate, with supernatural qualities. At a higher grade of development they have created gods made with hands, visible images of their fears or their desires, by whose worship and service they assuaged the urgent need within their breast. Still later, turning from such crudity, they became servants and worshippers of unseen gods, conceived under the form of persons, but persons transcending human personality, beings in whom was vested the control of man and of the world.

Up to this point there had been an increase of spirituality in the constructions by which human thought satisfied its need; none the less, the ideas underlying the mode of these constructions had not materially altered. As Voltaire so pungently put it, man had created God in his own image.

What remains? there remains to search in the external world, to find there if possible a foundation of fact for the belief drawn from the inner world of mind, to test the conceptions of a supreme being or supereminent power against ever more and more touchstones of reality, until the most sceptical shall acknowledge that the final construction represents, with whatever degree of incompleteness, yet not a mere fragment educed to fill a void, however inevitable, to satisfy a longing, however natural, but the summary and essence of a body of verifiable fact, having an existence independent of the wishes or ideals of mankind.

It was the striving after some such certainty that led Matthew Arnold to his famous definition of God as "something, not ourselves, which makes for righteousness." Dissatisfaction with the assertion that belief in a very special and undemonstrable form of Divinity was necessary as an act of faith has, in a large measure, helped the widespread revulsion against orthodox Christianity. It was the need for some external, ascertainable basis for belief which led such different minds as William James and H. G. Wells to approach religion, and in such diverse ways as in the "Varieties of Religious Experience" and in "God the Invisible King." It is this same need which is leading the representatives of Christianity to lay ever greater stress upon the reality and pragmatic value of the religious experience, less and less upon dogmas and creeds.

It will be my attempt in this brief paper to show how the facts of evolutionary biology provide us, in the shape of a verifiable doctrine of progress, with one of the elements most essential to any such externally-grounded conception of God, to any construction which shall be able to serve as permanent satisfaction of that deepest need whereof we have spoken.

Mr. Wells, if you remember, erected a new trinitarianism, which in broad outlines corresponded with this division. With his particular construction, I do not in many respects agree. But that some form of trinitarianism is a reasonably natural method of symbolizing the inevitable tripleness of inner experience, outer fact, and their interrelation is obvious enough. In the particular trinitarianism of Christianity, the reality apprehended to exist behind the forces of Nature is called the Father, the upspringing force within the mind of man, especially when it seems to transcend individuality and to overflow into what we designate as the mystical, is called the Holy Ghost, and the activity, personal or vicarious, which mediates between the individual and the rest of the universe, reconciling his incompleteness and his failures with its apparent sternness and inexorableness, is called the Son.

Some men lay more weight on one of these aspects than on the others. I know a clergyman of the Church of England who, on being reproached during a theological argument with failure to pay sufficient respect to the doctrine of God the Father, replied: "I am not interested in God the Father"; and I know intellectually-minded men who wish to reject the validity of all religious experience because their minds are so made that they pay more attention to external fact and because their reason refuses to let them agree with the interpretations of fact propounded by most religious bodies. But, for a properly balanced construction, for the finding of something which shall serve not as the basis of a creed for this or that sect, but of a creed for humanity, of something which instead of dividing shall unite, we need all aspects.

The idea of Progress constitutes, as I hope to show, the most important element in the first part of our construction--that which attempts to synthesize the facts of Nature; and besides, no inconsiderable portion of the third, the interrelation of inner and outer.

Readers of Bury's interesting book on the Idea of Progress will perhaps, with me, have been surprised at the modernity of that conception. He shows how, in antiquity, the idea was never a dominant one, and further that the adumbrations made of it all lacked some element without which it cannot be styled progress in the sense in which that word is used to-day.

It is, curiously enough, among the professional biologists that objectors to the notion of biological progress and to its corollary, the distinction of higher and lower forms of life, have chiefly been found. I say curiously enough, and yet to a dispassionate observer it is perhaps not so curious, but only one further instance of that common human failing, the inability to see woods because of the trees that compose them.

That is as it may be. Our best course will be to start by examining some of the chief objections to the idea of biological progress, in order to see if they involve errors of thought which we may then avoid.

The most widespread of all the objections raised may, I think, be fairly put as follows: "The fundamental attribute of living beings is adaptation to environment. A man is not better adapted to his environment than the flea which lives upon him as a parasite, or than the bacillus which kills him, nor is a bird better adapted to air than a jelly-fish to water; therefore we have no right to speak of one as higher than the other, or to regard the transition from one type to another as involving progress."

A second class of objector is prepared to admit that there has been an increase of complexity, an increase in the degree of organization during evolution, but refuses to allow that increase of complexity has any value in itself, whether biological or philosophical, and accordingly refuses to dignify this trend towards greater complexity by the name of progress.

Yet a third difficulty is raised by those who ask us to fix our attention on forms of life like Lingula, the lamp-shell, which, though millions of years elapse, do not evolve. If there exists a Law of Progress, they say, how is it that such creatures are exempt from its operations?

Finally, a somewhat similar attitude is adopted by those who refuse to grant that evolution can involve progress when it has, as we know, brought about well-nigh innumerable degenerations. Granted, for instance, they would say, that the average Crustacean is in many ways an improvement upon the simple form of life from which we must suppose that it arose, yet we know that within the group of Crustacea there are several lines of descent which have led to the production of parasitic forms--animals in which the activity and complex organization of the ancestral type has been sacrificed, and as end-product we are presented with a hateful being, an almost shapeless mass consisting of little else but over-developed reproductive organs and mechanisms for sucking nutriment from its unfortunate host. Such a result is revealed to us in the Crustacean form Sacculina, and is paralleled by countless other examples in almost every class of animals. The degradation of parasites and sedentary types is equally a product of the evolutionary process with the genesis of the ant, the bird or the human being; how then can we call the evolutionary process progressive?

Questions of fact are simple to deal with. It is indubitable that some forms of life remain stationary and unevolving for secular periods; it is equally indubitable that degeneration is widespread in evolution. These are facts. But we are not therefore called upon to deny the possibility of progress. To do so would be to fall into the error of reasoning which we have already condemned. It remains for us to take these facts into account when examining the totality of facts concerning organic life, and to see whether, in spite of them, we cannot discover a series of other facts, a movement in phenomena, which may still legitimately be called progress. To deny progress because of degeneration is really no more legitimate than to assert that, because each wave runs back after it has broken, therefore the tide can never rise.

Similarly with the first two objections. If the degree of adaptation has not increased during evolution, then it is clear that progress does not consist in increase in adaptation. But it does not follow that progress does not exist; it may quite well consist in an increase of other qualities. So with complexity. Complexity has increased, but increase in complexity is not progress, say the objectors. Granted: but may there not be something else which has increased besides mere complexity?

Let us then begin our survey of biological evolution in the endeavour to find whether or no progress is visible there. To start with, we must be clear what are the sources of our knowledge on the subject.

Direct observation of progressive evolution has, of course, not yet been possible in the period--biologically negligible--in which man has directed his attention to the problem; and historical record is also absent. The best available evidence is that of paleontology: here the relative positions of the layers of the earth's crust enable us to deduce their temporal sequence--and naturally, that of the organisms whose fossil remains they embalm--with a great deal of accuracy.

We can scarcely ever observe the direct transition from the forms of life in an older to those in a younger stratum, nor can we absolutely prove their genetic relationship. But in a vast number of cases it is abundantly clear that the later type of organization is descended from the former--that a group of forms in the younger stratum had its origin in one or more species of the group to which the forms in the older stratum belong. Sometimes, however, as in many groups of mammals, the gaps are few and small, the seriation almost complete. In any event we have here evidence which, so far as it goes, is perfectly admissible for the main lines and for many of the smaller branches of evolutionary descent.

Within the vertebrate stock, then, we can learn a great deal from the semi-direct methods of paleontology: but for the history of the other groups and for their origin and interrelations, we are driven back upon comparative anatomy and embryology, into another field of more circumstantial evidence. When, for instance, we find that the fore-limbs of bat, bird, whale, horse, and man, although so different in function and in detail of structure, are yet built upon the same general plan, and upon a plan wholly different from that of the limbs, say, of a spider or an insect, we must either deny reason and say that this similarity means nothing; or assume that its cause is supernatural, outside the province of science, that it is the expression of some eternal Idea, or some plan of a personal creator ; or finally that it implies community of origin with later divergence of development. When we are dealing with the smaller sub-divisions of some larger group, this method too gives us information of the same order of accuracy as does paleontology: but when we try to understand the relationships of these larger groups, then we are forced to renounce any claim to detailed knowledge. In broad outline, however, a great deal still remains, and this broad outline we can employ for our valuation of the whole sweep of biological progress, just as we can use the greater accuracy of vertebrate paleontology and comparative morphology to fill in the detail within a restricted field of its operation. From these various evidences, direct and indirect, we can paint for ourselves a picture of the evolution of life which, in spite of inevitable gaps and errors, is in its main features adequate and true.

Let us not be misled by the fact that disputes can and justifiably do arise over details: as Professor Bateson put it recently:--

"If the broad lines do not hold, then we must sink into irrationality or turn to flagrant supernaturalism."

Let us then remind ourselves of some of these broad lines.

We know that there was a time when the earth, hot and fiery, could not have been the abode of life. Of the first origins of life we know nothing and guess little. What we can justifiably surmise is that the protoplasm of the original organisms was not yet differentiated into cytoplasm and nucleus, and that sexuality had not yet arisen. The bacteria, however specialized in other ways, are still in this primitive condition.

Later, we can with great probability infer that the independent units into which the stuff of life was subdivided reached a size which, though still minute, was at least not beyond or even close to the limits of microscopic vision; they were further provided with a nucleus, and occasionally underwent sexual fusion. In other words, they showed an organization which we call cellular; they were free-living cells. Such unicellular creatures must have been at one epoch sole inhabitants of the earth, and diverged into the most manifold types of structure and modes of life. Such of them as led an animal as opposed to a plant type of existence would be classified under the Protozoa or unicellular animals.

The colonial habit gives advantages of increased size and greater rapidity of motion, of which many Protozoa have availed themselves. A colonial existence once attained, division of labour, at first between the germinal and the somatic, later between different types of somatic units, will be a further advantage. Such organisms, of which we cannot say definitely whether they are compound aggregates or single wholes, would represent the most natural link between the unicellular Protozoan and the rest of the animal kingdom, the multicellular forms or Metazoa. And indeed such organisms exist at the present day--organisms such as Volvox, Zoothamnium, Proterospongia, and Myxidium--as adjuvant and confirmatory of our reasonable faith.

The multicellular organisms appear to have originated twice over, by divergent routes. There are the true Metazoa, to which belong all the higher types, and the Parazoa or sponges, which have never passed beyond a very primitive type of structure. Both start as simple sacs, whose walls are formed from two primary sheets or layers of cells. Leaving sponges out of account, the Hydroid polyps are the simplest representative of this grade of structure, while some of the Jelly-fish and Siphonophores have attained the utmost limit of its inherent possibilities.

The next great step was the intercalation of a third primary layer between the other two. The result of this, the so-called triploblastic type of organization, gives the ground-plan for all subsequent organizations; and later evolution consists mainly in the evolution of this ground-plan.

In other words, we can now pass from the consideration of the general plan of life's architecture to that of its details. During the next great tract of time, that which was novel in life was brought about in two main ways--by an increase in the size of organisms, and by an increase in the efficiency of their working.

The simplest Metazoa, such as the polyps, as well as the simplest three-layered forms, such as the free-living flat-worms, are all small, composed of an amount of material comparable with that contained in a single one of our hairs. In every group of Metazoa, increase of size is one of the main features that accompanies specialization, and the more specialized groups possess a higher average size than the less.

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