Chapter VIII: Evolution and the Higher Human Life 278 (9)

The evolution of the wonderfully varied societies found among insects begins with the solitary insect itself, just as this, viewed as a cell-community, originates from one-celled beginnings like _Amoeba_ through progressive evolution in time. The similarity between social insects and human associations is clearer than in the case of a comparison between an example from either group and a cell-community, because the higher forms lack the organic contact of the components which is so prominent a feature in the lower instance. The social bonds are looser and they allow a freer play of the constituents; but nevertheless the same laws that control the activities of the cells making up what we now take as the individual element, command obedience on the part of the interrelated members of an insect community with equal strictness.

A butterfly or a moth is primarily egoistic and unsocial in the ordinary sense during its entire life-history, until the final reproductive act which has a value to the species. The caterpillar larva devotes all of its energies to feeding and growing, unconcerned with the final duties of the moth with which it is connected just as the indifferent unit of a young _Volvox_ colony is related to a reproducing member of the full-grown organism. Now and then, it is true, species like the so-called tent caterpillar are met with where numerous larvæ spin silken communal nests to which they retire at night and in which they remain to molt. The pupa, like the larva, is individualistic and employs its time in producing the final adult form. The mature individual, however, is constructed almost solely for the greater purpose of perpetuating the species. Indeed the larger silkworm moths do not and cannot feed, and their value is only that of a device for keeping the race established. Adult may-flies live only a few minutes, just long enough to provide for the fertilization and deposition of the eggs, although to prepare for these acts the young individuals must have toiled for months; the preparatory time may amount to many years in such a case as the seventeen-year locust. But nature is satisfied, as long as the organic mechanisms obey her double commandment, "Live and grow so as to multiply." Like an _Amoeba_, the solitary insect must be egoistic at first, in order to be altruistic in a racial sense in its last days.

Wasps, bees, and ants provide many familiar examples of colonial organizations that become all the more marvelous on closer acquaintance, on account of their resemblances to human associations on the one hand, and to cell-associations on the other. Their illustrative beauty is enhanced by their wide variety, for they grade from counterparts of highly civilized men down to a savage among insects, such as the strictly solitary digger-wasp, whose instincts served to exemplify the insect type of "mentality" in the discussions of the preceding chapter.

The true communities founded by wasps and hornets must be assigned to a low grade in the scale because they originate during a single season and break up at its end; for this very reason the wasp community is intensely interesting to the student of comparative social evolution. In the spring a solitary female emerges from the crevice where she has hibernated and resumes active life; she feeds for a time to renew her strength and then she constructs a simple nest of mud or masticated wood-pulp. In the first few cells of this nest she deposits her eggs, and when they hatch she herself provides the larvæ with food, but still continues to enlarge the house and to produce more eggs. Thus during the first few weeks of the colony's existence this single individual performs a variety of tasks of racial as well as of purely egoistic value; but as time goes on, a profound change comes about in her activities and in the life of the whole community. The members of the first brood do not grow into counterparts of their mother; they are all sexless "workers" who progressively relieve their parent of the tasks of nest-building and foraging and nursing, so that their mother becomes a "queen" who devotes her entire time to the special reproductive task which she only can perform. We may justly compare the queen to the reproductive organ of _Hydra_, for the values to the life of the species are identical in the two cases, while the various classes of workers are counterparts of such units as the muscle and nerve and nutritive components of the _Hydra_ or any other cell-community individual. Another resemblance between the two is found in the death of all the sexless individuals at the end of the season, when reproducing males and females are finally formed, of whom the fertile queens only survive in their winter hiding places; and again we can discover the cause for biological death in that division of labor which calls upon certain members of the whole community to perform tasks that have no value when once provision has been made for perpetuating the species. Finally the mode by which the colony grows and amplifies is in all respects like the embryonic development of an egg into a _Hydra_, so that we may add the phrase "social embryology" to our vocabulary. The original female is an undifferentiated master of all trades; the small tribe she first establishes is little better off than a horde of savages; but during its seasonal existence the community increases in numbers and complexity until it advances well toward the civilized condition, when each class performs its special task for the good of all.

The bees take us higher in the scale, although many solitary species occur, as well as social forms like the bumblebees where colonies are formed in a single season only to break up with the advent of cold weather. The honeybees, however, establish permanent communities from which swarms may set out during the warm months to become new colonies elsewhere. Many hundreds of bees make up a hive, and they belong to three classes or castes, which differ in structure and social function. The queen is a fertile female, the drones are males, and the workers are stunted and infertile females which take no part in reproduction. In this case the queen never discharges any menial duties, for these are attended to by the workers; she devotes her entire time to laying eggs, which are cared for by her subjects, who act as nurses and guards for the monarch as well. The young workers serve at first as doorkeepers, and only later do they take the field in the search for nectar and pollen, and work as house-builders. Each individual performs its special task for its own benefit and for the weal of all; each possesses an equal right to share in the prosperity of the whole community so long as it acts altruistically as well as egoistically. And just as the welfare of _Hydra_ is superior to that of any one of its constituent cells, so the well-being of a hive of bees may be safeguarded only by the actual sacrifice of some of its members. Should food supplies be inadequate, the superfluous drones are stung to death,--the victims of legalized murder. But more marvelous still is the provision that is said to be made by certain individuals for their own destruction should this become desirable. As every one knows, a reigning queen may leave the hive with many of her subjects and "swarm" in a new locality. When she does this, during the warm months, the workers of the original hive feed some of the female larvæ with richer food, and place these potential queens or princesses in special roomy cells apart from the ordinary brood chambers; one of them soon emerges to become a new sovereign. Let us note in passing how similar this is to the production of new egg-cells in a _Hydra_, when the mature germs of an earlier generation are prepared and discharged. When, now, the colder weather sets in, and the possibility of subsequent swarming is set aside, the reigning queen is allowed by her attendant guards to visit the royal cells, whose occupants she stings to death, thus destroying any possible claimant to her place. And when the royal princess constructs her part of the pupal case, she leaves an aperture so that if and when it should become necessary for the queen to kill her, the sovereign would not injure her sting and be unable to kill the other individuals who might become aspirants for the throne and so precipitate a civil war! As in the case of the self-destructive act on the part of a stinging cell in _Hydra_, altruistic subservience to the interests of the colony can go no farther.

The ants form stable colonies of still higher grades, where the workers are not all alike in general structure, but become more rigidly specialized for the performance of restricted tasks. As before, there is the fundamental differentiation into the sexual "queens" and males, and the sterile workers concerned with the immediate material life of the community. In some species the workers serve as herdsmen, caring for the ant-cattle or aphids, from which they receive minute drops of a sweet juice for food. The aphids are tended on the leaves of various plants during the summer, and are carefully reared and stabled and fed below ground during the winter months. In other species seeds are procured and stored in underground granaries. The leaf-cutters are forms which grow food supplies of fungi in subterranean mushroom gardens; the compost consists of cuttings brought from the leaves of bushes by myriads of workers, whose processions are guarded by larger-headed soldiers of several ranks. In the honey-ants of Colorado and tropical America certain individuals pass their time suspended from the roof of a large nest-chamber, where they receive the sweet juice brought in by the workers. They serve as animated preserve jars, distended sometimes to the size of a grape with the communal stores of food, which they return to the workers when external sources of food may fail. Finally there are the slaveholding species which conduct forays upon the nests of other forms, to procure the young of the latter, which grow up in their captors' nests and serve them as nurses and masons and foragers. So long has this custom been established that some slaveholders are entirely unable to feed themselves, and would die out if their slaves failed to support them.

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Let us pause at this point to summarize the results of the foregoing analysis, in order that we may approach the biological study of human associations with definite and clear conceptions of the fundamental laws controlling living communities of all grades.

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.

Are we to forget all of these things when we try to put in order our ideas belonging to the categories of higher thought? Can we hope to find the truth if we fail to employ the methods of scientific common-sense which only yield sure results? It is no more justifiable to discard our hard-earned knowledge than it would be for an advocate to undertake the conduct of a case in deliberate disregard of what he had learned of the law, or for a surgeon to leave his knowledge at the door when he entered the operating room. Too often we are bidden to view the larger conceptions of nature and supernature as something outside the realm of ordered knowledge too frequently we are given statements upon authority that takes no account of reason, and we are asked to accept these views whether or not they accord with the demonstrated facts of common-sense. But those who have followed the present description of evolution can readily recognize their obligation to use for the further analysis of higher human life the means which have given in that doctrine the most reasonable explanation of the natural phenomena already investigated.

I need hardly say that we now enter upon the most difficult stage of our progress. The regions we have traversed were more readily explored because they were remote from the matters now before us; even in the case of man's mental and social evolution it was possible to take a partially impersonal view of certain of the essential elements in human life, which we cannot do now. For ethics and religion and philosophy are groups of ideas that are familiar to us as the property of mankind alone. Countless obstacles are in the way. Much mental inertia must be overcome, for it is far easier to accept the average and traditional judgments of other men--to let well enough alone--than it is to win our own way to the heights from which we may survey knowledge more fully. Human prejudices confront us as a veritable jungle, hemming us in and obstructing our vision on all sides; and perhaps much underbrush must be cut away if we are to see widely and wisely. Nevertheless, to those imbued with a desire to learn truth, anything and everything gained must surely repay a thousand times all efforts to obtain clearness of vision and breadth of view. With our perspective thus rectified by our backward glance, we turn to the three divisions of human thought now to be examined. The conceptions of ethics come first for reasons that must be apparent from the classification of the facts of social evolution; just as mental attributes and communal organization are inseparable, so rules of conduct arise _pari passu_ with the origin of a biological association. Religion and theology form the second division, which takes its origin in part from the first, for these two groups of ideas are largely concerned with the authority for right conduct and with human responsibility for taking the right attitude toward the entire visible and unseen universe. Finally, science and philosophy are briefly treated as evolved products which include within their scope all that there is in human knowledge; for this reason they take the highest place, instead of the position below religion usually assigned to them. At the last, having reached our final standing ground, we must look back in order that we may clearly define the lessons and ultimate values of the whole doctrine of evolution.

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Ethics is the science of duty. It is usually restricted to an examination of purely human obligations, and to a search for the reasons why men should do certain things and refrain from committing other acts. Like psychology and sociology, ethics began as a strictly formal and _a priori_ system of dogmas which related to the life of cultured human beings alone. Again, like the sciences specified, it gradually broadened its scope so as to include the conventions of races lower in the scale than the civilized peoples who only were sufficiently advanced intellectually to conceive it. Thus the comparative method came to be employed, and in direct proportion to its use, more liberal views have developed regarding the diverse methods of thought and standards of social life and of conduct among differently conditioned peoples. Still more important is the demonstration that human ethics as a whole, like human faculty and civilization, takes its place at the end of a scale whose beginnings can be found in lower organic nature.

Those who have followed the account of social evolution given in the preceding chapter must realize that the basic general principles of natural ethics, as contrasted with "formal" ethics, have already been discovered and formulated. A biological association of whatever grade and degree of complexity is impossible unless biological duties are discharged. Human ethical conduct differs from insect and protozoön ethical conduct only in the element of a participation in the process by the explicit consciousness of man that he has definite obligations to others; and this distinguishing characteristic is the direct outcome of an evolution which adds reflection and conceptual thought to a mental framework derived from prehuman ancestors. The insect hurries about in its daily life as an animated machine, whose activities are defined by heredity; its special mode of conduct is just what nature has produced by selection from among countless other forms of living which have not had the same degree of biological utility. But man alone recognizes vaguely or clearly the "why and wherefore" of his acts that are far more instinctive than he supposes; he only is consciously aware of the bonds of kinship and economic interdependence. He looks about for the authority which imposes his duties and fashions his bonds, and conceives this authority as something superhuman, until the comparative studies of evolutionary phenomena reveal the true causes in uniform nature itself.

According to biological ethics, the fundamental obligations of all living things are the same, even though the modes of discharging them may be various. Every individual must lead an efficient personal life by procuring food, but animals differ very much in their alimentary apparatus; among other things they must respire, but some are so simply organized that they do not need elaborate organs like the tufted gills of a crustacean or the lungs of higher vertebrates. Every individual of whatever grade must also provide in some way for the maintenance of the species, but some, like a conger eel, produce enormous numbers of eggs which are left uncared for, while others, like birds, bring forth only a few young, which receive constant attention and protection until they are able to shift for themselves. Nature has no place for even a human community unless individual and racial interests are conserved, so that the greatest duties are definitely formulated--all else is secondary and less essential. Selfish action on the part of every unit is obligatory, but it must always be antecedent to endeavor in the wider interests of the race if the unit is a solitary individual; if it is a member of an association of any grade, then it must serve its fellows in some way. Egoism and altruism are natural essential guides to conduct; neither can safely exclude the other, and their antithesis sets a problem for every organism, which is to work out the proper compromise that will be most satisfactory to nature. The Golden Rule is taught by biology because it is demonstrated empirically, and not because it has any _a priori_ value as an ideal ethical principle.

But utilitarian or natural ethics need not stop with the statement of vague generalities like the foregoing. In human society, as in the life of low animals, the worth and value of any form of conduct and of every single act can be estimated by definite biological criteria. The institution of marriage and the conventions of common morality have their biological value in their provision for the care of children; the safeguards of property rights enable the industrious--the biologically efficient--to keep the fruits of their labors; the establishment of formal civil and criminal laws is biologically valuable in a social way, in so far as such laws diminish the unsettling effects of personal animosity and the desire to wreak personal vengeance; the establishment and differentiation of legislative, executive, and judicial organs of government lead to greater social solidarity and higher biological efficiency. Thus unchecked individualism is just as wrong ethically and biologically among men as it would be in the case of insect communities, as pointed out in the preceding chapter; no one has a right to expect service or deference to personal interest from others if he fails to work for them and for the good of all. It is true that the social structure will stand a great amount of tension, but if this becomes too great, either a readjustment is effected, as when King John was forced by the barons to concede their rights, or else the whole nation suffers, owing to the selfishness of a few. In the war between Russia and Japan, the latter won because the individual soldier merged his individuality in the larger mechanism of the regiment and brigade and army corps, gladly sacrificing his life for the nation represented by the person of its Emperor. The single Russian soldier may have been far superior to a Japanese in muscular strength, and perhaps in arms also, but selfishness and greed on the part of many who were responsible for the organization and equipment of the Russian armies rendered the whole fighting machine less coherent and therefore less efficient than that of the Japanese.

In the evolution of ethics the recognition of ideals of conduct has followed long after the institution of a particular precept by nature, which is obeyed instinctively and mechanically by force of inheritance. In the case of the communities of insects, the results are the same as though the individual animal fully recognized the value of concerted endeavor. So among primitive savages of to-day there is only a vague conception of abstract duty as such, or it may be practically lacking, as in the case of the Fuegians. So also a growing child is substantially egoistic, and it must be taught by precept and example that the rights of others can be safeguarded only by the altruistic correction of personal action, long before the child can grasp the higher conceptions of ethics. If a human being never learns to do so, and becomes a criminal through force of heredity or circumstances, the machinery of the law automatically comes into operation to conserve the welfare of the community. Such a criminal may be unable to control his destiny, and may not be responsible for being what he is, but nevertheless he must pay the penalty for his unsocial heritage by suffering elimination.

Ethical systems are built around man's vague recognition of certain natural obligations, and they have thus become more or less complex, and more or less varied as worked out by different peoples. They must necessarily be much concerned with social questions, with morals in the usual sense and the more rigid principles enacted into the spoken and printed law, but they have also become closely connected with religion and theological elements. Especially is this true in the ethics of barbarous and savage peoples, who accredit the "categorical imperative" to some supernatural power, as we are to see in a later section. The one point that comes out clearly is that the systems of conduct and duties have evolved so as to be very different among various races, and that in the history of any one people, ethics has passed through many varied conditions. What may be deemed right at one period becomes wrong at another when conditions may be changed; in medieval England the penalty of death was prescribed for one who killed a king's deer, as well as for a highway murderer. The Fijian of a quarter century ago killed his parents when they became too old to be effective members of their tribe. And so deeply ingrained was this principle of duty that elderly people would voluntarily go to a living grave surrounded by their friends; while in other authentic cases, parents have first killed their sons who failed to obey the tribal law, and have then committed suicide. We can see how nature and necessity would institute a law requiring such conduct where a tribe must carry on almost incessant warfare and where the available food supplies would be enough for only the most efficient individuals. Infanticide also has been practised for reasons of biological utility, as among the Romans, who at first maintained their racial vigor by deliberately ordering the death of weak babes. But times have changed, and ethics has become very different with passing decades. Our civilization has resulted in a development of human sympathy as an emotional outgrowth of necessary altruism; this motive directs us through charitable institutions and hospitals to prolong countless lives which are more or less inefficient, but which do not render the whole body politic incompetent in its struggle for existence.

Nature then has itself attended to the development and institution of ethics. As we look back over the long series of stages leading to our own system of conduct the most striking feature of the history is the increasing power of self-control or inhibition. As a natural instinct this tends to prevent the committing of acts which for one reason or another are naturally harmful to society as a whole. What we call conscience is an instinct implanted by purely natural factors, and it unconsciously turns the course of human action in the directions of selfish and altruistic interests. Conscience, then, without ceasing to have validity and efficiency, appears on the same plane with all of the other products of evolution which owe their existence to individual or social utility.

Theology and religion involve intimately related conceptions of the world, its make-up, and its causes. Strictly speaking, religion is a system of piety and worship, while theology deals more particularly with the ultimate and supernatural powers conceived in one way or another as the God and the gods who have constructed the universe and have subsequently ordered its happenings. A religion is a group of ideas having the effect of motives; it is dynamic and directs human conduct. Theology, on the other hand, is more theoretical and descriptive, and its conceptions, together with those of other departments of human thought, give the materials for the formulation of the religious beliefs which determine the attitudes of men toward all of the great universe in which they play their part and whose mysteries they attempt to solve.

Defined and distinguished in these ways, these two departments of higher human life present themselves for comparative study and historic explanation. They differ much among the varied races of mankind, so much, indeed, that an investigator who approaches their study with a knowledge only of Christian religion and theology finds it difficult at first to recognize that the same fundamental ideas, although of far cruder nature, enter into the conceptions of an idol-worshiping fanatic living in the heart of Africa. But, nevertheless, beliefs that fall within the scope of the definitions adopted above are to be found among all men, and they must be examined so that their agreements and differences may be demonstrated, and their common elements may be explained as the natural products of a process of evolution.

Such a broad comparative study, like that of physical, mental, and social phenomena discussed heretofore, must be conducted objectively; that is, each and every particular belief of a religious or theological nature which can be discovered in any race is entitled to a place in the array of materials which demand scientific treatment. They must be verified, classified, and summarized, in order that their total meaning and value can be discovered. It must be strongly emphasized that for such purposes the inherent validity and truth or falsity of diverse religions are not called into question when they are so considered as objects of study; many still entertain the view that the mere task of conducting an analysis of a group of religious beliefs of whatever nature must tend to destroy or alter that system of religion in some way and degree. But whatever the comparative student may himself believe, the conception of Jehovah in the Hebrew religion is quite as legitimate an object of study as the Buddhistic concept of Brahma as the Ultimate Being, or the Polynesian idea of Tangaroa as the god of the waves. We would naturally be inclined to exclude the last from our own personal system of piety and worship as the childish concept of an imaginative, adolescent race; but whatever the truth may be, the fact of a belief in Tangaroa is as real as the fact of Christian belief in God. We can no more destroy any one of these ideas by investigating its nature and origin than we destroy the efficacy of the human arm when we study its muscles and bones and sinews. The former, like the latter, take their places among natural phenomena whose history must be inquired into if there are any reasons for supposing that they fall within the scope of evolution. I would be the last to lead or to take part in an attack upon any system of religion, but as a student who is interested in the universality of organic evolution, I am forced to scrutinize each and every authentic account of a religion to see if such systems present objective evidence of the fact of their evolution through the operation of purely natural causes.