The Doctrine of Evolution: Its Basis and Its Scope

Chapter 20

Chapter 203,920 wordsPublic domain

We have dealt mainly with _Amoeba_, _Hydra_, and the ant-community which exemplify three somewhat distinct types of organic individuality. Some of the transitional forms have been specified to show how the second kind originates from the first, and how in its turn this grows in time into the third and most complex association; thus _Vorticella_ and _Volvox_ connect _Amoeba_ with the cell-community individual like _Hydra_ and a solitary wasp, while the annually established colonies of social wasps and of bumblebees lead to the permanent colony-individual. Restricting attention to the three primary examples, and remembering that the criterion of completeness is the ability to discharge satisfactorily all of the eight biological tasks, it is clear that the entire _Hydra_ and the whole ant-community correspond _physiologically_ with _Amoeba_, although the first-named is _structurally_ a cell-community equivalent to many protozoa, and the insect colony is composed of many such cell-communities as elements. In the third type, neither a single queen nor a single worker is able to carry on all of the biological tasks any more than a muscle-cell or an unformed egg of _Hydra_ can maintain itself capably in isolation. Therefore the ant-society as a whole and the _Hydra_ in its entirety are organic individuals on the same physiological plane with _Amoeba_, and they are equally subject to the same great laws of nature demanding selfish maintenance and racial perpetuation.

But we must not lose sight of the fundamental value of the unit during the evolution of a higher from a lower type. The tissue-cell of _Hydra_ must still obey the mandate to live an efficient personal life, because this is necessary for the welfare of other cells and of the whole complex. The original egoistic tasks are not abolished, but new duties are added to them in ways we have learned to distinguish. In _Vorticella_ the products of fission do not separate, and certain advantages accrue from the organic continuity thus maintained. The success of _Hydra_ in its ceaseless struggle to live depends wholly upon the cooperation of its differentiated cell-units, now no longer equivalent in function to the all-powerful _Amoeba_, although each one must be kept alive until its task is done, or the whole association would have no place in nature. Similarly in the higher insect community, the superadded duties to fellow-components are even clearer, for in the competition of colony with colony, involving terrific battles whose casualties may be numbered by thousands, the stronger wins; and strength depends upon the concerted efforts of all the members of the kingdom, that only collectively constitute a complete biological whole. Mere self-protection demands altruistic conduct: if the worker ceased to bring in food when its own hunger was satisfied, there would be no tribal stores for the stay-at-home queens and nurses; and if the soldier fled from the field of battle to save its own life, its act would be suicidal ultimately, for to the degree of one unit the defense of its non-military supporters would be weakened and they would be so much the less unprotected during their service for the soldiers and all others. Furthermore, we must admit the reality of natural criteria of ethical values, established far below mankind in the scale of life. In an ant-republic, laws are instinctively obeyed quite as implicitly as though they were intelligibly proclaimed to all of the emmet citizens. Right is might when community battles with community, for right is that which is biologically favorable. And what may be correct conduct on the part of the members of one species may be naturally wrong and evil in another case. To kill the princesses in order to obviate the possibility of civil war seems advantageous and therefore right when the queen remains in the persistent colony of honeybees, ready to do her part the following spring; but it might result in disaster and evil in the case of the social wasps, where the community dies as such in the fall, and the continuity of the species from one year to another requires the production of many queens lest the severe conditions of the winter's hibernation should kill all fertile females if only one or two were available. The standards of conduct are simple indeed; and whether or not it may seem best to separate the processes of social and ethical evolution culminating in human phenomena, the fact remains that these processes begin with elements discovered by the biologist among organisms of the lower levels in the scale.

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We come at length to the biological interpretation of human social evolution, in so far as this may be expounded in a simple and concise form. The comparative method must be employed in order to discover the fundamental attributes of savage, barbarous, and civilized communities which seem to differ so considerably in their complexity of social structure, and in order also to show that such basic elements are like those of communities formed by lower animals, and are equally the products of natural evolution. This whole subject seems to be exceedingly complex, because in our daily contact with others of our kind and in our occasional views of foreign races like our own, the smaller details occupy our attention, diverting it from the great basic principles according to which every society is organized and operates. But when once the major elements have been discovered in civilized and more primitive nations, the secondary and less essential phenomena fall into their proper relations, and a statement of the whole process of development becomes relatively simple. So much space has been devoted to lower types of communal organisms in order to learn what the fundamentals are, and not merely to provide analogies that may be useful hereafter. It now remains to arrange the evidences of social progress during the history of mankind itself, and to bring such human facts into relation with what has been discovered in lower nature. It is helpful to begin this part of the subject by asking ourselves what is already part of common knowledge about human history. Do we know of any civilized nation that is absolutely stable and unvarying in social structure, or one that has remained unchanged throughout historic time? The answer must be negative, for in no case does the past disclose an example of permanence in social or in any other respect; monarchies and republics are plastic like the human frame itself. The American Commonwealth is a relatively young social organism, and it is an easy task to trace its growth from beginnings in the diffuse and uncorrelated colonies of pre-Revolutionary years. Those colonies that were formed by English settlers were transplanted outgrowths from a civilized social parent which in its turn had clearly evolved from the state of King John's time and the still cruder form it had under King Alfred.

Should we follow back the recorded history of any people now civilized, we would always find evidence of ceaseless change; and the writings of ancient historians like Herodotus and Cæsar and Tacitus give a great deal of information about the barbarous conditions from which civilization evolved.

But much more is known that materially amplifies the account of human progress based upon documents alone. The student of existing human races early learns that social structure is a very varied thing. The natives of northern Africa now live in a semi-civilized state which is very like that of medieval England. In Siberia and the American Southwest are tribes that correspond socially with the barbarians of Europe described by Greek and Roman writers. The American Indians discovered by the earliest colonists, the Polynesians of a century ago, and the Fuegians of recent decades provide counterparts of the ancient stone-wielding people who were the savage ancestors of European barbarians. Hence the comparative study and classification of modern races establishes a scale of social grades which corresponds with the order of their historic succession, just as in a larger way the complete series of comparative anatomy from _Amoeba_ to man displays the order of evolution from unicellular beginnings to the present culminating types. Savagery, barbarism, and civilization are the three major terms of this social scale, but by no means are they discontinuous, for many intermediate forms of organization occur which are transitional from one major type to a higher one.

In human social evolution the starting point is not so simple as the solitary unit from which insect societies evolved,--that is, an organism which lives alone and is associated with another of its species only at the time of mating. The lowest human beings now existing have some form of family organization, traceable to the more or less continuous unions formed among certain of the apes and even among many lower animals, and not a characteristic that belongs to mankind alone. The savage and his mate constitute the social unit out of which all else is built up; the man and the woman must perform all of the vital tasks demanded by nature. Fruits and vegetables must be secured from the wild forest or by cultivation; the flesh of game animals or of a human victim is no less essential for food. The savage is his own weapon maker and warrior; he himself builds the rude shelter for his family and fashions the canoe if such is required. He is also his own judge, recognizing no control save the dictates of his wishes and needs, for he does not consciously realize that he must obey the primal commands of nature to preserve himself and his family so that the species shall persist. In brief, the elementary family unit carries on all of the individual biological tasks of foraging, righting, home-building, and the like, and it also discharges the racial task of multiplying, quite as instinctively as it provides for its own maintenance.

By the union of several families, a primitive association arises, like that of the Veddahs in Ceylon. The primal duties of each family are unchanged, and their biological activities are identical, as in the protozoön colony of _Vorticella_ or in a pack of wolves; but certain new relations are established. A member of such an inchoate tribe must not treat his confrères as he might a man of another group; robbery and murder within the limits of the small association are detrimental to communal interests, though they may remain unchecked if the victims are strangers. Coöperation for mutual offense and defense makes the group stronger than its constituent family units taken singly, and every man of such a tribe gains something by looking out for others as well as for himself. By natural selection alone the bonds of union would be strengthened in direct proportion to the subordination of individual interest to group welfare, and to the amount of altruistic action that in a true sense grows out of purely selfish conduct.

But when such a primitive biological association forms and grows, an opportunity arises for increasing the effectiveness of the whole group by differentiation. Some of the men are stronger in battle and they soon become the chief warriors; others prove to be more skilful in the hunt or in the construction of canoes and weapons. Just as among the insects, the hunter seeks food not only for himself but for the warriors, who in their turn defend themselves, but do not cease fighting when they have disposed of their own enemies if foes of their comrades still survive. The barbarous state of society thus arises, and the division of labor brought about during its origin makes it possible and indeed essential for many family units to remain together for mutual good. The union is stable and efficient, however, only if the individual suppresses his own selfish inclinations, suspending private quarrels when public wars are toward, and acting at all times in concert with his fellows. Self-control increases necessarily, and lines of conduct deemed right by a solitary savage unit come more and more under the sway of social inhibition, for although the primitive savages must inhibit individualistic action to some degree, the barbarian must suppress much more of his purely personal wishes for the purpose of social solidarity. Thus it comes about that a barbarous community can number thousands, while a tribe of savages with a higher degree of individualism and less altruism cannot cohere if it comprises more than hundreds or scores.

Civilization is a product of evolution by precisely the same natural mode of development, that is, through further subordination of individual to communal interests and through progressive dividing up of the tasks necessary for the life of the group. The final result is so obvious and familiar that we take it for granted, accepting it as self-sufficient without realizing how it has come about and how modern is the present state of affairs. Let us compare the life of an Indian savage living on Manhattan Island four centuries ago with that of a New Yorker to-day, as regards so simple a matter as the procuring of fish food. The Indian emerged from his tepee, built by himself, and walking to the shore, stepped into a canoe which also he had made with his own hands. Paddling to the fishing ground, he patiently cast his line until the desired fish were caught. Does any one of us do all of these things for himself? We live in houses constructed for us by others who devote their lives to building; we are very apt to go about the city in conveyances that demand special and peculiar skill for their invention, manufacture, and operation. Arriving at a market-place, we obtain such an article of food as a fish without having to go out upon the water ourselves, for many other workers have built vessels that we do not know how to make and may not know how to handle, and hundreds of fishermen devote their lives to their special task, not for themselves, but for us and all others, such as the builder, the subway operator, the boat maker, and the manufacturers who supply their clothing and apparatus.

What has come about then is a higher degree of specialization in the performance of the fundamental biological tasks, resulting in the formation of coherent and efficient groups comprising millions as compared with the thousands of barbarism and the hundreds of savagery. Just so the communities of insects with the greatest degree of altruism and division of labor far exceed in numbers the small colonies of the social wasps with lower social differentiation.

But the great biological functions of an entire complex civilized society remain the same as those of a primitive savage family unit, of an insect community, of _Hydra_, and of _Amoeba_. Let any nation fail to maintain itself in material individual respects, it must inevitably die out; in the islands of the South Seas many a tragic death-struggle of a people can be witnessed. If in the second place a nation should concern itself too greatly with the material benefits of human life without obeying the natural mandate to propagate itself, its place in the scheme of things becomes insecure, as in the case of the French Republic. Natural social laws that go back to _Amoeba_ must be observed, consciously or unconsciously, or else even the civilized community must fall, like scores and hundreds of others that lie along the road of historic progress--a road strewn with the remains of the unfit thrown out by natural selection.

What now are the lessons of social evolution and what guidance does science give for human endeavor? Although it may seem that the biologist leaves his field when he considers these questions, his duty would be unfulfilled if he neglected an opportunity to give his results their highest utility through their use for the betterment of human life.

The first lesson is that the history of human social organization is far from unique, and that it is identical with the process by which insect communities and cell-aggregates have evolved; in a word, the laws of biological association are uniform throughout the entire organic scale. In some respects evolution in mankind has yet to equal the heights attained by some insects, inasmuch as no human society has accomplished so rigid a specialization of its members that a given individual is foreordained by its inherited structure to be a particular kind of worker and nothing else. Furthermore, evolution in human society is still far short of a state where some and some only are reproductive members of the group while the others are necessarily sterile; social insects with stable colonies are so organized that the queens and drones are solely reproductive while the workers are destined to care for the material wants of the colony. It is true that the birth-rate is by no means the same in all classes of society, but the social and other adventitious restrictions that bring this about are not on the same plane with the hereditary determining factors which operate among insects. Therefore the scale of human communities proves to be only a part of the wider range of organic associations in general--a part which can be definitely placed in such a wider scheme and so become more intelligible in itself.

In all departments of social evolution, progress is made by the twofold process of combination and differentiation. We have dealt with detailed instances, and now it is profitable to treat the process in a larger way, with a view toward the possibilities of the future. The Thirteen Colonies, somewhat similar in their earlier economic activities, united for mutual support much as wolves combine to form a pack. Later, as circumstances directed, they differentiated into farming or manufacturing or commercial organs of the body politic, each to some degree freeing itself of the functions undertaken by others, and becoming thereby more dependent than before upon those that specialized in different ways. As in the history of the insects in a growing wasp community and of savages evolving into barbarians, the original condition of relative independence passed into a state of interdependence and cooperation. In like manner, if nature remains the same, as there is every reason to believe it will, nations now separate will unite to make more complex combinations that will be veritable empires of world-wide scope. Countries on opposite sides of an ocean are now more closely connected by lines of communication and means of travel than were the Carolinas and New England a century ago. Diplomatic activities give many signs of a growing appreciation of the value of reciprocal agreements for mutual advantage, and the Hague Conference is a concrete manifestation of a continuing process of social evolution that finds its beginnings and its interpretation far below human history in lower organic nature.

But perhaps the most important result of this whole discussion is the lesson of social service that it teaches. We are members of a vast community whose complex total life seems far removed from anything going on in an ant-colony, and our daily tasks vary greatly in specific character and degree when compared with those of lower communal organisms. It seems scarcely credible that any principles of social relationship, however general, can hold true for us and for them. But when the rock-bottom foundations are reached, they are simple and instructive indeed. Being here, we cannot escape our personal obligations as living things or our equally clear duties as members of our community. These facts being as they are, what must we do? Self-interest is rightly to be served, otherwise we would be incapable of discharging our secondary tasks, namely, those of service to others in ways that are determined by hereditary endowment and conditional circumstances. The difficulty is to find the right compromise between the two sets of obligations; but the right balance must be found, or else the health of the community is impaired. Should any class demand more than its just dues, others must suffer through the diversion of what they require, and the well-being of the selfish class is jeopardized to some degree, so closely interwoven are the interests of all. Freedom of opportunity within the limits of ability and efficiency is the right of every one, but freedom of conduct must never result in trespass upon the equal rights of others to make the most of their abilities and opportunities.

To summarize, then, social evolution is a continuous process accomplished through differentiation and division of labor among the components of biological associations. Although the total form remains the same everywhere, progress has been made in content through the further subordination of selfish to altruistic conduct; only by this means does an individual gain liberty to pursue the social task for which he is best fitted by nature.

VIII

EVOLUTION AND THE HIGHER HUMAN LIFE

We have now reached the last division of the large subject that has occupied our thoughts for so long. The present title has been chosen because the questions now before us relate to the highest human ideas belonging to the departments of ethics, religion, theology, science, and philosophy. These matters may seem at first sight to be far removed from the territory of the naturalist as such, and quite exempt from the control of laws which determine the nature and history of the human individual in physical, mental, and social respects. Yet one reason alone would impel us onward: we cannot close the present examination into the basic facts of evolution and into the scope of the doctrine without asking to what extent a belief in its truth may affect our earlier formed conceptions of nature and supernature. Heretofore these possible effects upon what may be dearly cherished intellectual possessions have received no attention, so that we might learn how evolution works in the lower fields of organic life in general and human life in particular without being disturbed by them. No doubt, however, the conviction has grown with each step in our progress that the principles we have learned must cause us to readjust our views of the highest elements in human thought to a degree that must be inversely proportional to our previous acquaintance with the laws and processes of nature. But the seeker after truth is fearless of consequences. He knows that truth cannot contradict itself; and if those to whom he looks for authority give him conflicting accounts of nature's history, he knows that one of these must be less surely grounded than the other. The investigator soon learns to withhold final judgment, realizing that the primary conditions for intellectual development are the plasticity and openness of mind that dogmatism and finality destroy. He knows that while his researches may be, and indeed must be, iconoclastic, they provide him with better icons in place of the old.

Let us recall the steps in our progress through one and another field of knowledge, from which representative facts have been chosen for classification and summary. We began with the basic principles of organic structure and workings, and then we examined serially the larger categories of the evidences relating to evolution as a fact, and to the mode of its accomplishment by natural factors. Proceeding to the special case of our own species, we learned that human beings are inevitably a part of nature and not outside it; in structure, development, and palæontological history, mankind is subject to the control of the uniform laws which operate throughout the entire range of living things. Finally, the mental characters and the social relations of human organisms were derived from beginnings lower down in the scale, and were proved to be no more exceptional than the physical constitution of a single human being.