Part 6

In any case, the changes which would confer advantage in the struggle for existence may take place in any direction--with, or against, or at right angles to the stream of progress. By means of those which march with that stream, the upper level of life’s attainment is raised. But the struggle still goes on: and again, starting from this new condition, there will be variations in every direction which will have survival value, and some of these will be progressive; and so the upper level will be once more raised.

The process will take time, for, whatever theory of variation we may hold--the old idea of small continuous variations; or that of large mutations big enough to produce new species at one jump; or the most probable theory of numerous small mutations--they one and all must grant that the largest variation occurring at one time in a living species is infinitesimal in comparison with the secular changes of evolution.

There will further be a premium upon progressive changes, since a progressive change will generally land its possessor in virgin soil, so to speak; if not in an actually new physical environment, then in a biologically new situation. The placental mammal occupies the same dry land as did the wonderful reptilian types of the Secondary epoch. But constant temperature and embryonic nutrition within its mother provide delicately adjusted conditions in the early phases of development which in their turn enabled a more elaborate and more delicately responding brain machinery to be constructed in development, and so advanced their possessors on to new shores of control and independence.

There will thus be a constant biological pressure (to use a term which, though still symbolic, a mere analogy, is less misleading and question-begging than élan vital) tending to push some of life on to new levels of attainment, new steps in progress, because any variations in that direction will have selection value, a selection value above the ordinary. And the process will be a gradual one, because variations are not very large; so that life no more realizes all potentialities of progress at once than did the United States or any other new country receive a uniform population over all its extent as soon as it was discovered, but had its people move in from the coasts in a regular and orderly advance.

There are plenty of parallels from human affairs. Indeed, the evolutionist can often gain valuable light on his subject, on what one may call the economics of the process, by turning to study the development of human inventions and machines. There, although the ways in which variations arise, and the way they are transmitted, are different from those of organic evolution, yet the type of “pressure,” the perpetual struggle, and the advantage of certain kinds of variation therein--these are in essence really similar.

What could be more striking than the parallel between the rise of the mammals to dominance over the reptiles, and the rise of the motor vehicle to dominance over that drawn by horses?

In both cases, a comparatively long period in which the new type is in a precarious and experimental stage, only just managing to exist, of small size and rare occurrence, and in no real sense a serious rival to its old-established competitors. Then, suddenly, a change. It reaches a level at which it can effectively compete with them. What happens? In the case both of man-made machine and evolving vertebrate group, there is first a sudden increase in numbers of the new, a corresponding decrease in numbers of the old type. The upper level of size of the new type also begins to increase, and it begins to split up into a great number of differentiated sub-types. Some of these sub-types become extinct, others, on the other hand, are gradually improved, while still others undergo such rapid change as to merit the style of new sub-types. The upper level of size, complexity, and efficiency increase, both in animal and machine.

It is as well to remember that survival-value means only what it says. A variation with survival-value helps its possessors to survive: it is not the best possible variation of the kind. In the developing motor-car, the substitution of four for one or two cylinders was a great improvement. It had “survival-value”; and not until the majority of cars came to be four-cylindered was the additional advantage of six or eight cylinders large enough to bring them into existence as dominant types.

To the interrelated evolution of carnivore and herbivore, again, leading to increase of size and speed in both, of wariness in one, of tooth and claw in the other, we have again a close parallel in the interrelated evolution of armour-plating and of projectiles. Here again the process is gradual. We can further see that the sudden “development” of full modern armour on the first iron-clad would have been actually disadvantageous, since it would have reduced its speed relatively to other less heavily protected ships, without conferring any corresponding benefit in the way of defence against the comparatively inefficient projectiles of the day. Only when the range and piercing power of the projectiles increased did increase of armour become imperative.

To resume our pressure analogy, the natural increase of all organisms leads to a “biological pressure.” So long as a species remains unchanged, so long must it stay subjected to the full force of this pressure. But if it changes in such a way that it can occupy a new niche in environment, it is expanding into a vacuum or a region of lower pressure. Natural increase soon fills this up to the same level of pressure, and conditions thus become favourable for expansion into new low-pressure areas previously out of reach of the normal range of variation. Variation towards such “low-pressure” regions may be progressive, retrogressive, or neutral: but it is obvious that at each stage of evolution there will always be a low-pressure fringe, representing a considerable fraction of the “low-pressure” area within the range of variability, the occupation of which would be biologically progressive.

Thus from the well-established biological premisses of (1) the tendency to geometrical increase with consequent struggle for existence, (2) some form of inherited variability, we can deduce as necessary consequence, not only the familiar but none the less fundamental fact of Natural Selection, but also the almost neglected fact that a certain fraction of the guiding force of Natural Selection will inevitably be pushing organisms into changes that are progressive.

This will of course be true only so far as the general conditions of the environment remain within certain limits: it is probable that too great reductions of temperature or moisture on the surface of the earth would lead to a gradual reversal of progress before the final extinction of life. Up to the present, however, it is clear that such conditions have not occurred, or, possibly, have occurred only for short periods. The general state has been one in which steady, slow progress has been achieved. Progress, like adaptation, is in pre-human evolution almost entirely the resultant of blind chance and blind necessity.

What corollaries and conclusions may be drawn from the establishment of the fact of biological progress? In the first place, it permits us to treat human progress as a special case of a more general process. Biologically speaking, the human species is young--not perhaps still in infancy, but certainly not yet attained to any stable maturity. The conception, common enough in much traditional thought, that man as a species is old, far removed from all pristine vigour and power, is demonstrably untrue. The genus Homo has not yet adapted itself to the new conditions and the new possibilities arising out of the acquisition of reason and tradition. Its history so far is a record of experiment after experiment. From a period so short and so empirical it is impossible to deduce any general law of progress. In certain respects, as we shall see more in detail later, there has been advance; in others, the species has been stationary. But whether humanity in this or that particular has progressed is for the moment comparatively immaterial. Humanity is part of life, a product of life’s movement; and in life as a whole there is progress.

What is more, there was progress before man ever appeared on the earth, and its reality would have been in no way impaired even if he had never come into being. His rise only continued, modified, and accelerated a process that had been in operation since the dawn of life.

Here we find, in the intellectual sphere at least, that assurance which men have been seeking from the first. We see revealed, in the fact of evolutionary progress, that the forces of nature conspire together to produce results which have value in our eyes, that man has no right to feel helpless or without support in a cold and meaningless cosmos, to believe that he must face and fight forces which are definitively hostile. Although he must attack the problems of existence in a new way, yet his face is set in the same direction as the main tide of evolving life, and his highest destiny, the end towards which he has so long perceived that he must strive, is to extend to new possibilities the process with which, for all these millions of years, nature has already been busy, to introduce less and less wasteful methods, to accelerate by means of his consciousness what in the past has been the work of blind unconscious forces. “In la sua volontade è nostra pace.”

For this is one of the most remarkable facts of evolution--that consciousness, until a very late period, has played in it a negligible part. Indeed the rise of consciousness to become a factor of importance in evolution has been one of the most notable single items of progress. Darwin gave the deathblow to teleology by showing that apparently purposive structures could arise by means of a non-purposive mechanism. “Purpose” is a term invented to denote a particular operation of the human mind, and should only be used where a psychological basis may reasonably be postulated. On the other hand, a result can be attained by conscious purpose without the waste of time and of living material needed by the indirect method of natural selection; and thus the substitution of purposed for unpurposed progress is itself a step in progress.

As another corollary of our concept of progress, it follows that we can and should consider, not only the direction of any evolutionary process, but also its rate.

An evolutionary process, if it is to be considered progressive, must have a component in one particular direction--a direction which we have already defined. But this is not all; for even if it be moving in the right direction, and yet be moving extremely slowly, it may, if it have any interaction with a much more rapid progressive movement, actually exert a drag on this; its relative motion--relative to the main current of progress--will be backwards, and we may have to class it as the reverse of progressive. For example, the interaction of carnivore and herbivore, pursuer and pursued, led during the development of the vertebrates to the evolution of much that was good--speed, strength, alertness, and acuity of sense--and of many noble types of living things. But with the advent of man, different methods have been introduced, new modes of competition and advance; and the tiger and the wolf not only cease to be agents of progress in its new form, but definitely stand in its way and must be stamped out, or at least reduced to a condition in which they can no longer interfere as active agents in evolution.

Some such considerations as these will help perhaps to resolve various difficulties of ethics--how, for instance, that which seems good to me may seem evil to another. Even the good, if it be a drag on the better, is evil. Expressed thus, the proposition is a paradox; but expressed in terms of direction and relative speed, it is at once intelligible.

But the test of any such general biological theory as I have outlined will be its application to human problems. And here too, I venture to say, the value of biological method is apparent. What we ask, and rightly ask, is whether in the laws of biological progress we can find any principle which we can apply directly to guide us in devising methods for human progress.

I do not propose to follow the example of many rather hasty philosophers and biologists, who have thought that, whenever the study of lower organisms permitted the promulgation of a biological law, such law can be lifted bodily from its context and be applied without modification to human affairs. Man is an organism--but a very exceptional and peculiar organism. Any biological law which epitomizes only facts about the lower creatures is not a general biological law, for general biological laws must take account not only of plants and animals, but of man as well. In practice, however, the simplest method is to frame our biological laws without considering man, and then to see in what way they must be modified if they are to be applied to him.

Man differs biologically from other organisms in the following main ways. First, he has the power of thinking in concepts; in other words, his power of learning by experience is not always conditioned directly by the accidents of his own life, as is the case with animals endowed only with associative memory, but he can, by reaching the general from the special, attain to the possibility of dealing with many more, and more complicated, eventualities. Next, by means of speech, writing, and printing, he has developed a new mode of inheritance. Each community, and indeed humanity as a whole, transmits its peculiarities to later ages by means of tradition, using that word in its largest sense. Physical inheritance of the same type as in all higher animals and plants is the necessary basis, but the distinctive characters of any civilization are based on this new tradition-inheritance. Thirdly, the type of mind which has been evolved in man is much more plastic--a much more elastic and flexible mechanism than any tool previously evolved by life for handling the problems of existence. As a consequence of this we have the substitution of general educability for specific instincts. For the power of performing comparatively few actions smoothly and without trouble, there is exchanged the possibility of a vastly increased range of action, but one which has to be learnt. As another consequence, man has come by the power--impossible to any other organism--of leading what is to all intents and purposes a multiple existence. It is for this very reason difficult to fit man into many of the ordinary biological categories. The physical and mental structure and the mode of life of even the highest of the animals are for all practical purposes a fixed quantity. An ant, for all its delicacy of adjustment, is little less than a sentient cog shaped to fit in just one way into the machinery of the community; a dog, for all his power of learning, is tied down and imprisoned within a rigidity and narrowness of bodily and mental organization difficult for us to imagine.

Man passes freely from one aggregation to another. He can change his nation or his city; he can belong to a dozen organizations--biologically speaking, can be aggregated in a dozen different ways--and play a different part as unit in each. He can follow one profession in the morning, another at night, and be a hobby-horse rider in between.

This plastic mind has endowed him with a new biological possibility. He can do what no other organism can--he can be both specialized and generalized at one and the same time.

In biology, the aggregation of units to form units of higher grade has been always followed by division of labour among the units; and this division of labour has, in all infrahuman history, been made possible only by an irreversible specialization. A soldier-ant is a soldier, and there its possibilities end. It cannot do what the worker or the queen can do. A muscle-cell, because it has gained the power to contract, is cut off from other possibilities; it cannot secrete, or digest, or carry messages. The aggregate of nerve-cells which makes the physical basis of mind is held fixed to its post, incapable of turning to other functions.

It follows that the units of all such aggregates are subordinate to the whole--they have lost their independence, and can often no longer be considered as individuals at all, except historically. But in man, none of these things hold. A man can for half his day be the merest cog, subordinate in every detail of his action to the needs of the community, but for the other half be himself, a full and complete individuality, making the community serve his own ends and needs. For him, aggregation does not mean complete and irreversible subordination; his specialization is reversible, and indeed his potentialities as an individual actually increase with the increased individuality of the aggregate to which he belongs.

Bearing these differences in mind, we may turn to consider how our doctrine of progress helps us in studying humanity.

At the outset we must guard ourselves against the idea that human society has reached any high level of biological individuation. I may perhaps quote from what I have written elsewhere: “If we were to draw a parallel between primitive types of society and some primitive mammal such as a duck-billed platypus, and to compare the course which we hope society will in time accomplish with what has been accomplished in the progress of the mammalian type from a creature resembling the platypus up to man, with what creature should we have to compare the existing state of human communities? I venture to say that we should be flattering ourselves if we were to fix upon the dog.”