Human Nature and the Social Order
Introduction: Heredity and Instinct
Charles Horton Cooley
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THE EVOLUTIONARY POINT OF VIEW—TWO CHANNELS OF LIFE— WHAT WE GET FROM HEREDITY AND WHAT FROM SOCIETY—OUR MODE OF LIFE DOES NOT ALTER THE HEREDITY OF OUR CHILDREN—SELECTION IN HEREDITY—EUGENICS—HEREDITY AND PROGRESS—INTERACTION OF HEREDITY AND SOCIAL ENVIRONMENT—ARE THEY ANTAGONISTIC ?—THE TEACHABILITY OF HUMAN HEREDITY—LONG INFANCY—TEACHABLE HEREDITY IMPLIES A DIVERSE AND CHANGING LIFE—WHAT IS INSTINCT?— INSTINCTIVE EMOTION IN MAN—EXAMPLES OF INSTINCTIVE EMOTIONAL DISPOSITION—HUMAN CONDUCT NOT TO BE EXPLAINED BY THE DIRECT WORKING OF INSTINCT—REASON AS ORGANIZATION OF PLASTIC INSTINCT—HUMAN HISTORY—WHAT IS HUMAN NATURE ? DOES HUMAN NATURE CHANGE ?
WE have come in recent years to look upon all questions of human life from an evolutionary point of view. It may be worth while to recall something of what that phrase means.
It means, for one thing, that all our life has a history, that nothing happens disconnectedly, that everything we are or do is part of a current coming down from the remote past. Every word we say, every movement we make, every idea we have, and every feeling, is, in one way or another, an outcome of what our predeces-
(4)-sors have said or done or thought or felt in past ages. There is an actual historical continuity from their life to ours, and we are constantly trying to trace this history to see how things come about, ;n order that we may understand them better and may learn to bring to pass those things we regard as desirable.
It means also that if we go far enough back we find that man and the other animals have a common history, that both sprang remotely from a common ancestry in lower forms of life, and that we cannot have clear ideas of our own life except as we study it on the animal side and see how and in what respects we have risen above the condition of our cousins the horses, dogs, and apes. Life, it appears, is all one great whole, a kinship, unified by a common descent and by common principles of existence; and our part in it will not be understood unless we can see, in a general way at least, how it is related to other parts.
The stream of this life-history, whose sources are so remote and whose branchings so various, appears to flow in two rather distinct channels. Or perhaps we might better say that there is a stream and a road running along the bank—two lines of transmission. The stream is heredity or animal transmission; the road is communication or social transmission. One flows through the germ-plasm; the other comes by way of language, intercourse, and education. The road is more recent than the stream: it is an improve-
(5)-ment that did not exist at all in the earliest flow of animal life, but appears later as a vague trail alongside the stream, becomes more and more distinct and travelled and finally develops into an elaborate highway, supporting many kinds of vehicles and a traffic fully equal to that of the stream itself.
How does this idea apply to the life of a given individual—of you or me, for example ? His body—and his mind too, for that matter—begins in a minute, almost microscopic, bit of substance, a cell, formed by the union of cells coming from the bodies of his parents, and containing, in some way not yet understood, tendencies which reach back through his grandparents and remoter ancestors over indefinite periods of time. This is the hereditary channel of his life, and the special kind of cells in which heredity is conveyed—called the germ-plasm—are apparently the only source of those currents of being, those dispositions, capacities, potentialities, that each of us has at the beginning of his course.
The social origin of his life comes by the pathway of intercourse with other persons. It reaches him at first through his susceptibility to touches, tones of voice, gesture, and facial expression: later through his gradually acquired understanding of speech. Speech he learns from his family and playmates, who, in turn, had it from their elders, and so it goes back to the earliest human history, and farther still to the inarticulate cries of our pre-human ancestors. And it is the same with the use of tools, with music, art, religion, commerce, and whatever else he may learn to think
(6) and do. All is a social heritage from the immemorial past.
We may distinguish these two lines of history more clearly, perhaps, if we take a case where they, are not parallel, where the road over which we get our social heritage has not followed the stream from which we get our animal heritage, but has switched off, as it were, from another stream. Suppose, for example, that an American family in China adopts a Chinese baby and brings it home to grow up in America. The animal life-history of that baby's past will lie in China. It will have the straight black hair, the yellowish skin and other physical traits of the Chinese people, and also any mental tendencies that may be part of their heredity. But his social past will lie in America, because he will get from the people about him the English speech and the customs, manners, and ideas that have been developed in this country. He will fall heir to the American political, religious, educational, and economic institutions; his whole mind will be an American mind, excepting only for the difference (if there IS any) between his inherited aptitude to learn such things and that of other American children. The Chinese stream and the American road have come together in his life.
If there were two such babies—twins, let us say, and almost exactly alike at birth—one of whom remained in China while the other was brought to America, they would grow up alike physically, and also, probably, in temperament, as active or sluggish, thoughtful or impetuous, but would be wholly different in dress,
(7) language, and ideas. In these the child bred i n America would be far more like his American fosterbrothers than like his twin-brother in China.
Just what is it that we get through the germ-plasm, as distinguished from what we get by social transmission? The former is evidently the main source of our bodily traits. The child of a dark race will be dark no matter in what society he grows up, and will have also whatever peculiarities as regards hair, shape of head, height, and the like belong to the racial type from which his germ-plasm comes. Nor is there any doubt, though it is not so obvious, that he gets from this source his original mental endowment. A child of feeble-minded ancestors is usually feeble-minded also, and one whose parents had unusual ability is apt to resemble them. Heredity brings us not only tendencies to a definite sort of physical development, but also capacity, aptitude, disposition, lines of teachability, or whatever else we may call the vague psychical tendencies that all of us are born with.
And from social transmission, through the environment, come all the stimulation and teaching which cause these tendencies to develop in a definite form, which lead us to speak a particular language, to develop one set of ideas or kind of ambition rather than another, to feel patriotism for America rather than for England or Italy. Everything in the way of specific function must be learned in this way, no matter what ability we have. When we say that a child is a born musician we mean, not that he can play or compose by
(8) nature alone, but that if he has the right kind of teaching he can rapidly develop power in this direction. In this sense and in no other can a man be a born lawyer, or teacher, or poet, or, if you please, a born counterfeiter or burglar. I knew a family in which the boys had a remarkable aptitude for football, several of them becoming distinguished players, but certainly unless they had all been sent to college, and to one in which football ability was prized and encouraged, this aptitude would never have been discovered.
It is an important question whether our mode of life alters the heredity that we transmit to our children, whether, for example, if I devote myself to study this fact will so affect the germ-plasm that my children are likely to have more mental capacity. The prevailing scientific opinion is that it does not, that, of two brothers, one who is uneducated, but of the same natural ability, is as likely to have bright children as one who goes to college and enters an intellectual profession. An athlete will not have stronger children because of his training.
An obvious ground for this view is that injuries or mutilations, such as the loss of a leg, are never inherited, not even if they are continued for generations, as was formerly the case with the feet-binding of certain classes of Chinese women. Nor do defects due to a non-hereditary cause, like the deafness that often follows scarlet fever, affect the offspring. In fact, notwithstanding much research, no one has been able to produce any satisfactory proof that "acquired traits,"
(9) that is those due to the mode of life, are ever transmitted through the germ-plasm.
As regards the theory of the matter, it is thought that, heredity being carried by the germ-plasm, and this being a special kind of cells not affected by our particular mode of life, there is no reason why the latter should change heredity. The germ-plasm, it is believed, bears individuals somewhat as a tree bears fruit, but they do not react upon it; they merely carry it and hand it on, as the apple carries the seed.
If this is true (and the evidence is so strong that we may at least accept it as the most probable theory to work by) it follows that we cannot improve the strictly hereditary factor in future children by teaching their parents, or even by bettering the life of the latter in any or all respects. It does not follow, however, that the germ-plasm will remain unchanged, even if we ourselves cannot change it. Apparently there is growth, or intrinsic change of some sort, going on in all life, and it is natural to presume that the germ-plasm is no exception. We need not suppose that nothing takes place in it but a mechanical recombination of ancestral elements: there are probably changes, but as yet we know little of their character. If one believes, in general, that life is mechanical and predetermined, one will naturally apply this idea to heredity as well as elsewhere, but if he believes that it is in some sense free and creative, there is no reason why the hereditary current should not share in these traits.
It is possible even if our mode of life has no direct effect upon heredity, for us to influence it by an in-
(10)-direct process known as Selection. This is based upon the fact that the germ-plasm carried by one individual may differ considerably from that carried by another, even in the same family, and varies widely as between different families, and still more widely as between different races; although all may have remotely a common ancestry. If, then, we know what sort of germplasm a certain individual or family or race carries, and can Increase or decrease the number of children inheriting it, we can change, more or less, the proportion which this kind of heredity bears to other kinds.
An obvious case is where two contrasted races are concerned. Suppose, for example, there is a Southern county in which there are five thousand negroes and five thousand whites, and that the average number of children raised in negro and white families is about the same. Now if, in some way, you can cause the white families to raise more children, or the negroes fewer, the complexion of the county will gradually be altered. If the rate becomes as three to two in favor of the whites, there will be three white children to two black in the next generation, ~ x i, or nine to four in the generation following, and so on in a geometrical ratio. The negroes will become a rapidly dwindling fraction of the population.
If, instead of having two distinct races in the county, we had merely the white race, in which. however, there was a considerable difference of complexion among the family stocks represented, something analogous might still take place. If the dark families were more prolific than the blonde, the population would darken' or
(11) vice versa. And even in the same family there might be differences in this respect which could be increased or diminished by selection. There is no doubt that, starting with a mixed population and being able to control mating and the number of children, we could in this way breed dark or light people, tall or short, blue-eyed or black-eyed, bright or dull, and indeed increase or diminish any hereditary trait ascertainable enough to be made the basis of selection.
It is believed that the conditions of life are all the time tending to cause some types of heredity to produce more children than other types, and so by an unconscious process to alter the germ-plasm in the group as a whole. For example, the frontier conditions in the early history of America probably tended to produce a physically vigorous race; not because the undergoing of hardships had any direct effect upon the germplasm, but because the weaker sort of people would be likely to die out under these hardships, and leave no children to inherit their weakness, while the stronger sort would leave large families and correspondingly increase the sort of germ-plasm that they carried—in other words by "natural selection" or "the survival of the fittest. " This process may in time produce very great changes. The difference in color between the black and white races (which are undoubtedly sprung from a common ancestry) is plausibly explained, on the principle of natural selection, by supposing that darker skins were associated with greater power of resistance to the heat of the sun, or to the diseases of tropical climates, so that this kind of heredity would
(12) increase in such climates; just as many species of animals are known to develop colors that help their survival. Most animals, including birds, are so colored as to be hard to distinguish from their environment: it is a kind of camouflage, and helps them to escape the enemies who would otherwise devour them or to approach the prey which would otherwise escape them.
It was by natural selection mainly, according to Darwin, that the various species of plants and animals were gradually moulded to fit the conditions under which they had to live, and any one who wishes to know something fundamental about evolution should read at least the first six chapters of his Origin of Species. And In his Descent of Man one may see how he worked out this idea in its application to the development of the human race.
But why not make selection conscious and intelligent, and thus improve the stock of men somewhat as we do that of domestic animals? There has, in fact, arisen a science of Eugenics, or Race-Improvement, seeking to stimulate the propagation of desirable types of human heredity and prevent that of undesirable types. There are many difficulties in this, and it is not clear how much we may expect to accomplish but there is no doubt that some things can and should be done. Scientific tests should be made of all children to ascertain those that are feeble-minded or otherwise hopelessly below a normal capacity, followed by a study of their families to find whether these defects
(13) are hereditary. If it appears that they are, the individuals having them should, as they grow older, be prevented from having children to inherit their incapacity. At present, owing to our ignorance and carelessness in this regard, large numbers of children are coming into the world with the handicap to themselves and the menace to society of an ineradicable inferiority.
On the other hand, the educated and prosperous classes show a tendency to limit the number of their children that is often spoken of as Race-Suicide. This limitation appears to be due partly to the taste for ease and luxury fostered by wealth, partly to increasing social ambition and greater desire for self-development. These latter, excellent no doubt in themselves, draw upon our means and energy, and are apt to cause us to postpone marriage or to have fewer children after marriage than we otherwise would. Since they grow with democracy, it may well be that democracy antagonizes the birth-rate.
It takes an average of nearly four children to a family to keep up the numbers of a hereditary stock, and more to maintain its proportion of an increasing population like that of the United States. This is because there must be enough not only to replace the two parents and provide for the increase, if any, but also to compensate for failure of propagation by the unmarried, the sterile, and those who die prematurely.
The upper classes are falling far short of their quota, and if we assume that they represent the abler stocks it would seem that the race is being impaired by their diminution. Is it not desirable, and perhaps practica-
(14)-ble, to induce them to become more prolific? Even if they do not represent abler stocks than the middle class, is there not danger that the small-family tendency will pervade that class also? It has already done so in France. Many people are alarmed also by observing that the immigrant stocks in the northern and eastern states are multiplying faster than the native stocks, and that the negroes are kept from outrunning the whites only by their high death-rate. Others give their apprehensions a still wider range and see an imminent Yellow Peril in the fecundity of the oriental peoples, which threatens, they think, to put an early end to the ascendancy of the white races and of white civilization.
Although improvements in our mode of life probably do not alter heredity, it by no means follows that they are unimportant, or less important than eugenics. In fact, progress, as ordinarily understood, does not require any change in heredity, but is a development of knowledge, arts, and institutions that takes place in the social process with little or no alteration of the germ-plasm. The spread of education, the abolition of slavery, the growth of railroads, telegraphs, telephones, and automobiles, the formation of a society of nations and the abolition of war—all this kind of thing is social and may go on indefinitely with no improvement in heredity. Nevertheless better heredity would make progress more rapid, because it would give us more men of talent as leaders and a higher average of ability. And a worse heredity, such as many think we are in danger of, would hinder progress
and possibly, in time, put an end to it altogether. Social improvement and eugenics are a team that should be driven abreast.
When our individual life begins the two elements of history from which it is drawn, the hereditary and the social, merge in the new whole and cease to exist as separable forces. Nothing that the individual is or does can be ascribed to either alone, because everything is based on habits and experiences in which the two are inextricably mingled. Heredity and environment, as applied to the present life of a human being, are, in fact, abstractions; the real thing is a total organic process not separable into parts. What heredity is, in its practical working at a given time, depends upon the process itself, which develops some potentialities and represses others. And in like manner the effective environment depends upon the selective and assimilating activities of the growing organism. If you wish to understand it the main thing to do is to study its life-history back to its beginning in the conception and birth of the individual; beyond that you may, if you wish, pursue still farther the germ-plasm and the social inheritance from which it sprang. These give us a background, like the accounts of a man's ancestry and early surroundings in the first chapters of his biography. But the life of William Sykes is a thing you must study directly, and no knowledge of heredity and environment can be more than a help to this. 
(16) Speech well illustrates the inextricable union of the animal and social heritages. It springs in part from the native structure of the vocal organs and from a hereditary impulse to use them which we see at work in the chattering of idiots and of the deaf and dumb A natural sensibility to other persons and need to communicate with them also enters into it. But all articulate utterance comes by communication, it is learned from others, varies with the environment and has its source in tradition. Speech is thus a sociobiologic function. And so it is with ambition and all our socially active impulses: We are born with the need to assert ourselves, but whether we do so as hunters, warriors, fishermen, traders, politicians, or scholars, depends upon the opportunities offered us in the social process.
Evidently it is wrong, speaking generally, to regard heredity and social environment as antagonistic. They are normally complementary, each having its own work to do and neither of any use without the other.
Which is stronger ? Which is more important ? These are silly questions, the asking of which is sufficient proof that the asker has no clear idea of the
(17) matter in hand. It is precisely as if one should ask, Which is the more important member of the family, the father or the mother? Both may be said to be infinitely important, since each is indispensable; and their functions being different in kind cannot be compared in amount.
Shall we say, then, that all discussions as to the relation between heredity and environment are futile? By no means The fact is that, although it is plain that they are, in general, complementary and mutually dependent, we usually do not know precisely what each contributes in a given case, and so may be in doubt whether to seek improvement by working on the germ-plasm or through social influence. It is only with reference to general theory that the question which is more important is silly. With reference to a specific problem it may be quite pertinent—just as it might be quite pertinent, as regards the troubles of a specific family, to inquire whether you could best reach them through the father or through the mother. And while direct measurement of the factors, at least where the mind is involved, is impossible, since they have no separate existence, there may be roundabout methods of inference which throw real light upon the matter.
Many race questions are of this sort. There are, for instance, great differences between the Japanese and the Americans. Some of these, as language, religion, moral standards, are clearly social and may be altered by education. Some, as stature, color and shape of the eyes, are certainly hereditary and cannot
(18) be altered by education: these, however, are, in themselves, perhaps, of no great importance. But are there also, or are there not, subtle differences of temperament, mental capacity or emotional gifts, which are both hereditary and important, which render the races incapable of living together in peace, or make one of them superior to the other? We do not know the answer to this question, though it is most important that we should. It is the same with the negro question. How far is the present inferior condition of that race remediable by education and social improvement, how far is it a matter of the germ-plasm, alterable only by selection ? The whole negro-white problem hinges on this question, which we cannot answer with assurance.
There is an analogous problem with reference to criminals. How far, or in just what sorts of cases, may we safely trust to educational or deterrent methods as a preventive of crime ? Should we also try to prevent propagation, and, if so, when and how? And so with men of genius. We need more of them. Will education do it, or shall we follow the teaching of Galton, the founder of eugenics, who held that we must above all things induce men of great ability to have more children ? And again, with reference to the rich and powerful classes. Is their ascendancy that of natural ability, of a superior breed, and so, perhaps just and beneficial ? Or is it based on social privileges in the way of education and opportunity, and hence, as many think, unfair and detrimental ? unsolved questions of this kind arise whenever we try to make out just how we may better the course of human life. At present the best we can do is to try everything
(19) that seems likely to improve either the germ-plasm or the social process.
Although the transmission of heredity through the germ-plasm is much the same in man as in the other animals, there is a notable difference in the kind of traits that are transmitted, and are found to exist at birth. This difference is in teachability or plasticity. The mental outfit of the human child is above all things teachable, and therefore, of course, indefinite, consisting not of tendencies to do particular things that life calls for, but of vague aptitudes or lines of teachability that are of no practical use until they are educated. The mental outfit of the animal, on the other hand, is relatively definite and fixed, giving rise to activities which are useful with little or no teaching.
This difference is fundamental to any understanding of the relation of man to the evolutionary process, or of the relation of human nature and human life to animal nature and animal life. We need to see it with all possible clearness and to follow out its implications.
Roughly speaking, then, the heredity of the other animals is a mechanism like that of a hand-organ: it is made to play a few tunes; you can play these tunes at once, with little or no training; and you can never play any others. The heredity of man, on the other hand, is a mechanism more like that of a piano: it is not made to play particular tunes; you can do nothing at all on it without training; but a trained player can draw from it an infinite variety of music.
A newly hatched chick is able to run about and to pick up small objects of a certain size and form which
(20) prove to be food, and to sustain its life. It scarcely needs education, and I am told by a breeder that the product of the incubator, having no link with the past of their race except the germ-plasm, get along as well as those that have all a mother's care. A baby, on the other hand, takes a year to learn to walk, and many, many more years to learn the activities by which he is eventually to get his living. He has, to be sure, a definite capacity to draw nourishment from his mother, but this is only a makeshift, an animal method to help him out until his more human powers have time to develop. In general, his wonderful hereditary capacities are as ineffectual as a piano when the player begins to practice. Definite function is wholly dependent upon education.
Thus the plastic, indeterminate character of human heredity involves a long and helpless infancy; and this, in turn, is the basis of the human family, since the primary and essential function of the family is the care of children. Those species of animals in which the young are adequately prepared for life by definite heredity have no family at all, while those which more or less resemble man as regards plastic heredity, resemble him also in having some rudiments, at least, of a family. Kittens, for instance, are cared for by the mother for several months and profit in some measure by her example and instruction.
More generally, this difference as regards plasticity means that the life-activities of the animal are com-
(21) paratively uniform and fixed, while those of man are varied and changing. Human functions are so numerous and intricate that no fixed mechanism could provide for them they are also subject to radical change, not only in the life of the individual but from one generation to another. The only possible hereditary basis for them is an outfit of indeterminate capacities which can be developed and guided by experience as the needs of life require.
I see a flycatcher sitting on a dead branch, where there are no leaves to interrupt his view. Presently he darts toward a passing insect, hovers about him a few seconds, catches him, or fails to do so, and returns to his perch. That is his way of getting a living: he has done it all his life and will go on doing it to the end. Millions of other flycatchers on millions of other dead branches are doing precisely the same. And this has been the life of the species for unknown thousands of years. They have, through the germ-plasm, a definite capacity for this—the keen eye, the swift, fluttering movement to follow the insect, the quick, sure action of the neck and bill to seize him—all effective with no instruction and very little practice.
Man has a natural hunger, like the flycatcher, and a natural mechanism of tasting, chewing, swallowing, and digestion; but his way of getting the food varies widely at different times of his life, is not the same with different individuals, and often changes completely from one generation to another. The great majority of us gain our food, after we have left the parental nest, through what we call a job, and a job
(22) is any activity whatever that a complex and shifting society esteems sufficiently to pay us for. It is very likely, nowadays, to last only part of our lives and to be something our ancestors never heard of. Thus whatever is most distinctively human, our adaptability, our power of growth, our arts and sciences, our social institutions and progress, is bound up with the indeterminate character of human heredity.
Of course there is no sharp line, in this matter of teachability, between man and the other animals. The activities of the latter are not wholly predetermined, and in so far as they are not there is a learning process based upon plastic heredity. The higher animals—horses, dogs, elephants, for example—are notably teachable, and may even participate in the changes of human society, as when dogs learn to draw carts, trail fugitives, guide the lost, or perform in a circus. And, on the other side, those activities of man which do not require much adaptation, such as the breathing, sucking, and crying of infants, and even walking (which is learned without instruction when the legs become strong enough), are provided for by definite heredity.
The question of the place of instinct in human life may well be considered here, since it involves not only the relation between human and animal heredity, but especially that distinction between fixed and plastic reactions to the environment that we have just discussed.
There is much disagreement upon the definition of
(23) instinct, some confining it to definite modes of hereditary behavior, like the squirrel's burying a nut; others giving it a much wider and vaguer meaning. To inquire how this disagreement arose will throw light upon the whole matter.
Animals, as we have seen, have definite and effective modes of acting which they do not have to learn, and it was these that first attracted attention, by their contrast to human behavior, and were called instinct, as opposed to the more rational or acquired activities of man. Darwin says in his Origin of Species:
"I will not attempt any definition of instinct . . . but every one understands what is meant when it is said that instinct impels the cuckoo to migrate and to lay her eggs in other birds' nests. An action, which we ourselves require experience to enable us to perform, when performed by an animal, more especially by a very young one, without experience, and when performed by many individuals in the same way, without their knowing for what purpose it is performed, is usually said to be instinctive. But I could show that none of these characters are universal." 
Men have few instinctive actions, in this original sense of the word. But when investigators began to study our behavior from the evolutionary point of view, they saw that if not instinctive in the strict sense it had yet grown out of instinctive behavior, was historically continuous with it, and, in short, that there was no sharp line to be drawn, in this matter, between human and animal. Moreover, although our outward actions had ceased to be determined by heredity, it
(24) seemed that we still had inward emotions and dispositions that were so determined, and had an immense influence on our conduct. The question, then, was, and is, whether human behavior, guided in a general way by these hereditary emotions and dispositions, shall be ealled instinctive or not.
Those who answer yes, would say that a man is acting instinctively when he is impelled in any degree by hunger, fear, rage, or sexual attraction, even though his mode of expressing these impulses is quite new. Those who say no, would mean that such action is not instinctive because not definitely predetermined by a hereditary mechanism. The transmission of behavior through the germ-plasm is their test. Hence the disagreement as to the place of instinct in human life. If we are to give it a large place it must be used in the former sense, that is, to mean an inner rather than an outer process, it must be defined in terms of motive rather than of specific action.
Perhaps a reasonable middle course would be to avoid the word "instinct" as applied to most human behavior, which has nothing of the fixity of animal instinct, and speak instead of "instinctive emotion," since the emotional side of our activity clearly includes a hereditary element which seems to remain much the same under the most diverse manifestations.
If we do this we shall still find that there is little agreement as to just what instinctive emotions there are, and how they work. The reason for this lack of agreement is that our experience bearing upon the
(25) question, although real and vivid, is yet elusive, hard to define and classify, subject to various interpretations. Thus the passion of love is the hackneyed topic of literature and conversation. Most of us have undergone it, have observed it in others, and are willing to impart what we know about it; yet who can say precisely what the essential phenomena are, or just what is inherited, and how this inheritance is awakened, modified, developed by experience? These are obscure questions, and perhaps always will be. There are similar questions with reference to fear, anger, grief, and the like. The student will find informing books that aim to elucidate these phases of life, analyzing and describing our modes of feeling, and tracing their probable evolution from animal instinct, but these works differ immensely in their views, and none of them is conclusive.
It is fairly clear that we have at least half a dozen well-marked types of instinctive emotional disposition that are social in that they concern directly our attitude toward other persons. I might name, as perhaps the plainest, the dispositions to anger, to fear, to maternal love, to male and female sexual love, and to the emotion of self-assertion or power. We may accept these as instinctive,
1. Because they appear to be universal in the human race, as shown by common observation, by introspection, by the evidence accumulated in literature, and by more or less scientific methods of study, such as those used by psychoanalysts. This universality
would not of itself prove them instinctive: they might be due to universal social conditions. It adds greatly, however, to the cogency of other reasons.
2. Because they are associated with physical reactions or modes of expression which can hardly be other than instinctive, many of them being practically universal among the human race and some of them found also among the apes. The clenching of the fists and teeth in rage, and the uncovering of the teeth as if to bite are an example of what I mean. Darwin investigated these in his Expression of the Emotions, but, owing to his belief that the effects of habit are inherited, he did not discriminate as clearly as we could wish between what is hereditary and what is learned from others.
3. Because they correspond to and motivate certain enduring types of function found not only in man but in other animals; because, in short, they are so deeply rooted in animal evolution that it would be strange if they were not instinctive. Human anger, for example, motivates conflict with opposing persons or other agents, being similar in function to the anger, clearly instinctive, of all the fighting animals. In the same way fear motivates escape from danger, with us as with all animals who have dangers to escape from, and so on. These instinctive emotions predetermine, not specific actions, but, in a measure, the energy that flows into actions having a certain function with reference to our environment. 
(27) Beyond such clearly ascertainable hereditary dispositions there are innumerable others, some of them, perhaps, equally clear, but most of them elusive, undefined, and disputable. Moreover, all such dispositions, including those mentioned, are rapidly developed, transformed, and interwoven by social experience, giving rise to a multitude of complex passions and sentiments which no one has satisfactorily elucidated. Indeed, as these change very considerably with changes in the social life that moulds them, it is impossible that they should be definitely end finally described. Each age and country has its own more or less peculiar modes of feeling, as it has of thinking. There is no finality in this field. 
Although instinctive emotion probably enters into everything we do, it enters in such a way that we can rarely or never explain human behavior by it alone. In human life it is not, in any considerable degree, a motive to specific behavior at all, but an impulse whose definite expression depends upon education and social situation. It does not act except through a complex, socially determined organism of thought and sentiment.
If, for example, we say "War is due to an instinct of pugnacity," we say something that includes so little
(28) of the truth and ignores so much that it is practically false. War is rooted in many instinctive tendencies, all of which have been transformed by education, tradition, and organization, so that to study its sources is to study the whole process of society. This calls, above all things, for detailed historical and sociological analysis: there could hardly be anything more inimical to real knowledge or rational conduct regarding it than to ascribe it to pugnacity and let the question go at that.
Much the same may be said of the employment of a supposed gregarious instinct, or "instinct of the herd," to explain a multiplicity of phenomena, including mob-excitement, dread of isolation, conformity to fads and fashions, subservience to leaders and control by propaganda; which require, like war, a detailed study of social antecedents. This is, as Professor Findlay remarks,  "an easy, dogmatic way of explaining phenomena whose causes and effects are far more complicated than these authors would admit." Indeed I am not aware that there is any such evidence of the existence of a gregarious instinct as there is of an instinct of fear or anger; and many think the phenomena which it is used to explain may be accounted for by sympathy and suggestion, without calling in a special instinct. It seems to me to be the postulate of an individualistic psychology in search of some special motive to explain collective behavior. If you regard human nature as primarily social you need no such special motive.
There is, indeed, a wide-spread disposition among psychologists, psychoanalysts, biologists, economists, writers on education, and others who are interested in instinct but would gladly avoid history or sociology, to short-circuit their current of causation, leading it directly from instinct to social behavior, without following it into those intricate convolutions of social process through which, in the real world, it actually flows and by which it is transformed. This is an instance of that common fallacy, particularism, which consists in attending to only one factor in a complex whole. Social questions, because of the many factors entering into them, offer peculiar temptations to this fallacy, against which we cannot be too much on our guard.
How are we to think of reason in relation to instinct ~ This depends upon our view as to that question, already discussed, whether instinct means only fixed modes of behavior or whether it may include also instinctive emotion that expresses itself in plastic behavior. If we confine it to the former, then instinct and reason exclude each other, because it is the nature of reason to adapt conduct to varying conditions; but if we admit the latter, then reason and instinct may work together. Fixed instincts call for no general control: life presses a button and the hereditary mechanism does the rest. But teachable instincts imply a teacher. They must be guided, developed, co-ordi-
(30)-nated, organized, so that they may work effectually; and this is the part of reason. Reason, in one aspect, is team-work in the mind; it is the mental organization required by the various and changing life sf man. It takes the crude energy of thc instinctive dispositions, as an offlcer takes his raw recruits, instructing and training them until they can work together for any end he may propose, and in any manner that the situation demands. If a man wants a wife it teaches him how, in the existing state of things, he may be able to woo and win her, and how support her when won, giuding him through a complicated course of behavior adapted to the present and yet impelled in part by hereditary emotion.
Reason, in this view, does not supplant instinct, any more than the captain supplants the private soldiers; it is a principle of higher organization, controlling and transforming instinctive energies. Indeed, reason is itself an instinctive disposition, in a large use of the term, a disposition to compare, combine, and orgamze the activities of the mind. Animals have it in some measure and it is unique in man only by the degree of its development: it might be compared to a common soldier emerging from the ranks, taking the lead by virtue of peculiar ability and becoming in time the commanding officer.
And human history, in distinction from animal history, is a natural outcome of those traits of human psychology that we have discussed. It is a process possible only to a species endowed with teachable
(31) instinctive dispositions, organized, partly by reason, into a plastic and growing social whole. This whole, responsive to the outer world in a thousand ways, and containg also diverse and potent energies within itself, is ever putting forth new forms of life, which we describe as progress or decadence according as we think them better or worse than the old. These changes do not require any alteration in our hereditary powers. The hereditary basis, the instinctive but teachable capacities, are relatively constant, and, so far as these are concerned, there is little or no reason to think that the Teutonic stocks from which most of us are sprung are appreciably different now from what they were when Caesar met and fought and described them. If we could substitute a thousand babies from that time for those in our own cradles, it would probably make no perceptible difference. They would grow up in our ways, driving automobiles instead of war chariots, reading the newspapers, and, in general, playing the human game as it is played to-day quite like the rest of us.
And, finally, just what do we mean by Human Nature? The phrase is used vaguely, but there are at least three meanings that can be distinguished with some precision. And as we distinguish them we may be able, at the same time, to answer the perennial question, Does Human Nature change?
It may mean, first, the strictly hereditary nature of man, borne by the germ-plasm, the formless impulses and capacities that we infer to exist at birth, but of
(32) which we have little definite knowledge because they do not manifest themselves except as a factor in social development. This nature appears to change very slowly, and we have no reason to think we are very much different at birth from our ancestors of, say, a thousand years ago. 
It may mean, second, a social nature developed in man by simple forms of intimate association or "primary groups," especially the family and neighborhood, which are found everywhere and everywhere work upon the individual in somewhat the same way. This nature consists chiefly of certain primary social sentiments and attitudes, such as consciousness of one's self in relation to others, love of approbation, resentment of censure, emulation, and a sense of social right and wrong formed by the standards of a group. This seems to me to correspond very closely to what is meant by "human nature" in ordinary speech. We mean something much more definite than hereditary disposition, which most of us know nothing about, and yet something fundamental and wide-spread if not universal in the life of man, found in ancient history and in the accounts of remote nations, as well as now and here. Thus, when we read that Joseph's brethren hated him and could not speak peaceably to him because they saw that their father loved him more than all the rest; we say, "Of course, that is human nature." This social nature is much more alterable than heredity, and if it is "pretty much the same the world over,"
(33) as we commonly say, this is because the intimate groups in which it is formed are somewhat similar. If these are essentially changed, human nature will change with thom.
There is a third sense of the phrase which is not unusual, especially in discussions which turn upon the merits or demerits of human nature. This is not easy to define, but differs from the preceding in identifying it with somewhat specific types of behavior, such as pecuniary selfishness or generosity, belligerency or peacefulness, efficiency or inefficiency, conservatism or radicalism, and the like. In other words, it departs from the generality of the idea and brings in elements that come from particular situations and institutions. Human nature, in any such sense as this, is in the highest degree changeful, because the behavior to which it gives rise varies, morally and in every other way, with the influences that act upon it. It may be selfish, inefficient, quarrelsome, conservative now, and a few years hence or in another situation generous, peaceful, efficient, and progressive; all turns upon how it is evoked and organized. Perhaps the commonest fallacy we meet in this connection is that which assumes that human nature does not change, points out respects in which it has worked deplorably, and concludes that it will always work so. An unchanging human nature, it is said, has given us wars and economic greed; it always will. On the contrary, since these things disappear or are controlled under certain conditions we may conclude that human nature, in this sense, is subject to change.
(34) But, in the more general sense, it is a nature whose primary trait is teachability, and so does not need to change in order to be an inexhaustible source of changing conduct and institutions. We can make it work in almost any way, if we understand it, as a clever mechanic can mould to his will the universal laws of mass and motion.