Essays of a Biologist — Text and Context

osed, in the first instance, of individual cells? Further, the investigation of the evolutionary process seemed to reveal certain general laws of its march: beings of the same original constitution, exposed to the environmental forces of the same planet, had reacted in similar ways, developing along parallel lines, and arriving at similar types of organization as end-result. Thus it might reasonably be supposed that we should find the same general organization and mode of development in one type of organism as in another, in human society as in a vertebrate.

On these bases, Spencer and his followers drew elaborate comparisons of the two, and apparently believed that they were reaching the same degree of accuracy as that found in comparative anatomy when they compared the circulatory system of a mammal with the transport facilities of a State, or drew parallels between the brain and the cabinet.

It was speedily seen, however, that such generalizations were so broad and vague as not to be of much service: that the resemblances were in fact often no more than symbolical or metaphorical, instead of being based upon detailed similarity of constitution or of evolutionary development. With this, evolutionary theorizing on sociological matters fell somewhat into disrepute. The earlier jubilant certainty gave place to later doubt; and the half-century whose beginnings had roused Haeckel and Herbert Spencer to their imaginative flights closed suitably enough with that remarkable document, T. H. Huxley’s Romanes Lecture, in which the greatest protagonist of Darwinism confesses to seeing between man and the rest of the cosmic process, in spite of man’s genesis from that same cosmic process, an insuperable and essential opposition, a difference of aim or direction which had turned the original bridge into a barrier.[18]

As a result, not only did the particular comparison between society and an organism fall into disrepute, but also all attempts to draw far-reaching conclusions from biology to human affairs.

But the original contention still remains, and is logically unassailable. Man is an organism descended from lower organisms; his communities are composed of units bound together for mutual good in a division of labour in the same way as are the cells of a metazoan: he can no more escape the effects of his terrestrial environment than can other organisms. There _is_ therefore reason to suppose that the processes of evolution in man and man’s societies on the one hand, and in lower organisms on the other, must have something important and indeed fundamental in common, something which if we could but unravel would help us in the study of both.

The correlation of biology with sociology is important not only in itself, but also as part of a more general correlation of all the sciences. The correlation of the sciences is of particular importance to-day for a double set of reasons. The rise of evolutionary biology and of modern psychology have not only changed our outlook on specially human problems, but have altered the whole balance, if I may so put it, of science. There was a time when the basic studies of physics and chemistry seemed not only basic but somehow more essentially scientific than the sciences dealing with life. Distinctions were drawn between the experimental and the observational sciences--often half-consciously implying a distinction between accurate, scientific, self-respecting sciences and blundering, hit-or-miss, tolerated bodies of knowledge. Biological phenomena are now, however, seen to be every whit as susceptible of accurate and experimental analysis; and indeed to present so many problems to the physicist and chemist that in fifty years or so, I venture to prophesy, the wise virgins in those basic sciences will be those who have laid in a store of biological oil.

But the main point is this--the study of evolution, of animal behaviour and of human psychology makes it clear that in the higher forms of animals at least we are dealing with a category not touched on at all by the physicist and chemist--the category of mind and mental process. Sir Charles Sherrington, with admirable lucidity, drew for us, in his recent address to the British Association, the problem of the relation between mind and matter as it presents itself to the biologist.

The great change that has come over science in the last half century, or so it seems to me, is the recognition that mind is not to be explained away as a mere epiphenomenon, but is to be studied as a phenomenon. From this point of view, biology will always be the connecting link between physico-chemical science on the one hand, and psychology on the other. There is every reason to suppose and no reason to doubt that life, which we know to be composed of the same material elements and to work by the same energy as non-living matter, actually arose from it during the evolution of this planet. There is, in the behaviour of the lower organisms, nothing which by itself would make us postulate mind: but in the higher insects, molluscs, and vertebrates, the last in particular, mental process is not only clearly present, but clearly of great biological importance; and finally the mind of man, according to innumerable converging lines of evidence, has evolved from the mind of some non-human mammal.

The principle of continuity makes us postulate that this new category of phenomena has not sprung up during the course of evolution absolutely _de novo_, but that it is in some sense universally present in all phenomena. It is merely that we have not yet found a method for the direct detection of mental processes as we have, say, for electrical processes; but something of the same general nature, the same category as mind must, if we wish to preserve our scientific sanity, our belief in the orderliness of the world, be present in lower organisms and in the lifeless matter from which they originally sprang.

In the present state of our knowledge, the study of physics and chemistry can be pursued without any reference to mental processes. But the study of biology cannot: and that is one reason why the centre of gravity of science as a whole is shifting--it is shifting for exactly the same reason that the centre of gravity of a house shifts during its construction--because the foundations have to be built first.

Our second reason is as follows. Biology is once more the link between root and flower, between physics and chemistry and human affairs, in regard to evolution. I say evolution: it would be better to broaden the idea by saying the directional processes to be seen in the universe. So far as a main direction is to be observed in physics and chemistry, it is, as all authorities are agreed, towards the degradation of energy and a final state in which not only life but all activity whatsoever will be reduced to nothing, all the waters of energy run down into a single dead level of moveless ocean. Biology, on the other hand, presents us with the spectacle of an evolution in which the main direction is the raising of the maximum level of certain qualities of living beings, such as efficiency of organs, co-ordination, size, accuracy and range of senses, capacity for knowledge, memory and educability, emotional intensity,--qualities which in one way or another lead to a more efficient control by the organism over the external world, and to its greater independence.

A direction towards more mind is visible; and this development of greater mental powers has been in all the later stages the chief instrument of acquiring control and independence. More and more of matter is embodied in living organisms, more and more becomes subservient to life.

Thus, while in physics and chemistry we see a tendency towards the extinction of life and activity, in biology we see a tendency towards more life and more activity; and this latter tendency is accompanied and largely made possible by the evolution of greater intensity of mental process--of something, that is to say, of which we cannot as yet take account in physics and chemistry.

The biologist may well ask himself the question--“Is it not possible that this evolving mind, of whose achievements on its new level in man we are only seeing the beginning, may continue to find more and more ways of subordinating the inorganic to itself, and that it may eventually retard or even prevent the attainment of this complete degradation of energy prophesied by physico-chemical science? Is it not possible that this great generalization only applies to phenomena in their purely material aspect, and that when we learn to detect and measure the mental aspects of phenomena we may find reason to modify the universal applicability of this law of degradation?” We do not know the answer to that question: but it is clearly a legitimate and useful question to ask. In any event, we constatate two chief directions in the universe; that seen in biology is in many ways opposed to that seen in physics and chemistry; and both must be taken into account.

I have spent, I fear, a great deal of time on what will appear to many as very irrelevant prolegomena. But the complete breakdown of the older views about nature and man, of the philosophies and theologies based not on observation but on an authority which is no authority, on unverifiable speculation, on superstition, and on what we would like to be so rather than on what happens to be so--the breakdown of all the commonly accepted basis for man’s view of himself and the universe, has made it necessary to go back to fundamentals if we are to see where we stand. Secondly, the progress of the biological and psychological sciences, as I have already pointed out, has considerably altered the outlook of those who pin their faith to the newer or scientific view of nature, the view which attempts constantly to refer speculations to reality, and to build on foundations which have been tested by experiment.

The orthodox evolutionary view was that phenomena received in some degree an explanation if their origin from simpler phenomena could be demonstrated. As a matter of fact, reflection makes it clear that such an explanation is never complete. It is a very incomplete explanation of the properties of water to discover that it is composed of oxygen and hydrogen; or of those of humanity to discover that it is derived from lower forms of life. A precisely similar mistake is made by most psycho-analysts, who consider that an “explanation” of adult psychology is given by tracing in it effects of the events of childhood. In all such cases it is true that analysis is helped, but we are by no means exempted from further study of the later (and more complex) phenomena in and for themselves. Just as adult psychology is qualitatively different in various respects from childish psychology, so is man qualitatively different from lower organisms. Very few attempts have been made to carry over conceptions derived from sociology into biology.[19] But the converse, as we have seen, has often been true, and numerous writers--largely because purely biological are simpler than human phenomena--have been obsessed with the idea that the study of biology as such will teach us principles which can be applied directly and wholesale to human problems.

What we have just been saying shows us the correct path. Through psychology and biology, sociology can become attached to the general body of science; and in so doing it can both receive and give. Since man is but a single species of organism, and, biologically speaking, a very young one; since moreover he presents a peculiar type of organization, it is clear that the broad principles underlying physiology and evolution can best be studied on other organisms and later applied to man. On the other hand, man is the highest existing organism; thus a study of the causes to which he owes his pre-eminence will be important as adding to and crowning the principles derived from non-human biology. Furthermore, not only are man’s mental powers on a different level from those of other animals, but psychology can at present make by far its greatest contributions by a study of human mind, so that the psychological side of biology will for the present derive its chief information from man.

Our first affair, therefore, is to see in what important respects man is qualitatively unlike the rest of the organic world; then to investigate what general rules or principles apply equally to him and to the others; and finally to see what corrections, so to speak, must be made before these principles can be applied to the one or to the other.

The qualitative difference between man and other organisms is a cardinal fact with orthodox biology has tended to slur over or to neglect, whereas philosophy has too often tried to magnify it unduly so as to make man frankly incommensurable with his lower relatives, a creature not only unique but disparate.

Man is obviously and undoubtedly an organism of the same general nature as other organisms. He possesses the same general system of organs, working in the same way as a dog, a horse, a bird, a crocodile, or a frog; he passes through the same type of developmental cycle; he is built on the same detailed plan as other mammals; and numerous indications betray his descent from a particular branch of the mammalian stock.

But in his mode of life and type of social organization he is unique. All detailed comparisons between the communities of man and those of bees and ants are as unprofitable in the working-out as they are easy in the making. It is futile to direct the sluggard or any other human being to the ant, since the whole physical and psychical construction of ants is different from that of man, the whole organization of their communities from that of his.

His mode of life is unique because his psycho-neural mechanism is built on a new plan, new modes of connection between parts of the brain being associated with new possibilities of mind. Let us briefly run over the biologically most important points in which he differs from the lower organisms.

In the first place, he is capable of speech, and possesses a true language--not a mere repertory of sounds or signs associated with different states of mind, as in some higher organisms, but a language comprising special symbols for particular external objects, and thus making it possible to have a much more detailed knowledge and classification of the outer world. In the second place, he can frame abstract ideas or concepts, and is thus enabled to extract the general kernel from the husk of innumerable separate and different particulars. As a result of these two faculties, he possesses what we may call a new, accessory form of inheritance. True biological inheritance takes place by means of the reproductive cells. In some birds and mammals, the behaviour of the young is modified by what they learn from their parents, so that they profit by the experience of their elders; however, this profiting by experience is not cumulative, but must be repeated afresh in each generation. In man, on the other hand, speech and writing make it possible to construct a continuous tradition, by means of which experience may be actually accumulated from generation to generation. There are thus two forms of inheritance in man, two hereditary streams--biological inheritance, by means of germ-cells or detached portions of the organism, in which favourable mutations may be accumulated by selection, and “experience-inheritance,” by means of tradition, in which useful experience may be accumulated by the activity of mind. By means of tradition-inheritance, man is virtually enabled to “inherit acquired characters”; thus the environment in which the latter stages of his development are passed through, and consequently his adult self, the end-product of that development, can be altered far more rapidly than in any other organism. Finally, it is possible, as is being increasingly realized, thus to accumulate experience relating to the alteration of biological inheritance, and so eventually to substitute conscious purpose for blind natural selection in man’s future evolution.

Next point: by means of speech, tradition, and invention, man has been enabled to extend his biological environment--in other words, that part of the cosmos with which he stands in relation--till it has reached an enormously greater size than that of any other organism. He is learning ever more facts about the celestial bodies, studying stars that are at an inconceivable distance from him. He is able to travel at will to all parts of the globe. He can penetrate by means of tradition to remote periods of the past: as Mr. Wells has forcibly put it, a modern Englishman can know more of the world in the Classical Epoch than could the most learned Greek or Roman. And even when he can no more get into contact with ideas, he can still unravel facts: flint implements help him to the history of man, fossils to that of life, rocks to that of the globe, stars to that of the solar system. In time, as well as in space, his environment enlarges to a size that is for practical purposes infinite, whereas no other organism can penetrate beyond its own memories, or, at most, do more than profit by those of the generation immediately before it. Professor Keyser,[20] in a suggestive article, has characterized this unique attribute of man by calling him “the time-binder.”

Speech and reasoning, with all their consequences, have only been rendered possible through another important qualitative change in the human brain, which in its turn has led to other new potentialities of life being realized in man and in man alone--its flexibility.

In some of the lowest forms of life, such as Paramecium, there are but one or two possible modes of reaction--reactions which it attempts in response to any one of the myriad changes that may occur in the outer world. As we ascend the scale, we find two chief types of alterations: in the first place an increase in the number of hereditarily-given modes of reaction, and in the second an increased power of “learning,” of altering behaviour in adjustment to experience. In the insects, the first is chiefly in evidence. Although many insects undoubtedly can profit by experience to a limited degree, yet most of their behaviour is instinctive, in the sense that it unrolls itself automatically and efficiently in the absence of previous experience or of any possible instruction. In the vertebrates, on the other hand, we see as we pass from the lower to the higher groups a definite, steady increase in the power of learning by experience, from the fish that takes weeks to associate a given colour with a given event such as feeding-time, to the dog or monkey capable of learning elaborate tricks after a couple of trials. But even in the most “intelligent” of birds or mammals, the power of image-formation is very probably absent,[21] and the power of concept-formation, of generalizing, certainly so. This fact (quite apart from the absence of tradition, although this too operates in the same direction) means that the associations of animals can only be arbitrary and individual: a rook in one country (to choose a somewhat far-fetched example) may happen to associate danger with fire-arms, one in another with bows and arrows. Life, for the animals, is a cinema, different for each individual, in which one event may be associated with another in the most diverse and haphazard ways. With the advent of the human type of brain, however, experience can be sorted out and properly docketed; the mere cinematographic record is converted into a drama full of significance, the diary into a card-index. By this means, and by tradition, it is possible for man to obtain a much more accurate and more complete grasp of the relationships of the objects that compose the outer world than is possible for any other animal. Through knowledge, as ever, comes power: and as a result, man has been enabled to invent tools and machinery, and so to enlarge enormously his control over his environment. Just as his “range,” in the zoogeographical sense, is extended to an unprecedented degree both in space and time, so tools represent, biologically speaking, an extension of himself as an operator. While man is using a tool, he and the tool together constitute but a single unit in the struggle for existence. As various writers have put it, tools and machines are temporary organs of man, which have the additional merit of being replaceable if lost or damaged.