[Footnote 2: _Ibid_. p. 108.]

But if differences in racial attainments are due to differences in environment, it might be said that this itself is testimony to the superiority of the race that has the more complex and exacting environment. This is not by any means clearly the case. The "culture" or civilization which a race exhibits is a very uncertain index of its gifts or its capacities. The culture found in a race is, it may be said without exaggeration, largely a matter of accident or circ.u.mstance rather than of heredity.

Some of the environmental causes for differences in culture may he explicitly noted. Any modern culture is the result of interminglings of many different cross-streams and cross-borrowings.

Races that have long been isolated as, for example the African negroes, have no possibility of picking up all the acquisitions to which races that intermingle have access. Progress in the developments of arts, sciences, and inst.i.tutions depends on fortunate individual variations. The smaller the race the less the number of variations possible, including those on the side of what we call genius. Again fortunate variations depend not so much on the general average intellectual capacities of the race as on its variability.

So one race may possess a relative superiority of achievement because of its high variability, just as, as we have already pointed out, the greater preeminence of the male s.e.x with regard to intellectual accomplishment is due to the greater number of variations both above and below the norm which it displays. The reasons for variability are again, according to Professor Boas, largely environmental. "We have seen, when a people is descended from a small uniform group, that then its variability will decrease; while on the other hand, when a group has a much-varied origin or when the ancestors belong to entirely distinct types the variability may be considerably increased."[1]

[Footnote 1: Boas; _loc. cit._, p. 93.]

Again a race may be placed in such geographical conditions that a fortuitous variation on the part of one individual may prove of enormous value in the development of its civilization.

Or fortunate geographical conditions may stimulate types of activity that lie dormant, although possible, among other races. Thus by some investigators the flexibility and emanc.i.p.ation of the Greek genius were attributed to their access to the sea and their constant intermingling with other cultures, especially the Egyptian.

On the subject of the fundamental equality of races despite their seeming disparity, as that at present, let us say, between whites and negroes, Professor Boas writes:

Much has been said of the hereditary characteristics of the Jews, of the Gypsies, of the French and Irish, but I do not see that the external and social causes which have moulded the character of members of these people have ever been eliminated satisfactorily; and, moreover, I do not see how this can be accomplished. A number of external factors that influence body and mind may easily be named--climate, nutrition, occupation--but as soon as we enter into a consideration of social factors and mental conditions we are unable to tell definitely what is cause and what is effect.

The conclusions reached are therefore, on the whole, negative. We are not inclined to consider the mental organization of different races of man as differing in fundamental points. Although, therefore, the distribution of faculty among the races of man is far from being known, we can say this much: the average faculty of the white race is found to the same degree in a large proportion of individuals of all other races, and although it is probable that some of these races may not produce as large a proportion of great men as our own race, there is no reason to suppose that they are unable to reach the level of civilization represented by the bulk of our own people.[1]

[Footnote 1: Boas; _loc. cit._, pp. 116, 123.]

In contrast must be cited the opinions of a large cla.s.s of psychologists and anthropologists who are inclined to regard racial differences as intrinsic and original. Of such, for example, is Francis Galton, who claims in his _Hereditary Genius_, that taking negroes on their own ground they still are inferior to Europeans by about one eighth the difference, say, between Aristotle and the lowest idiot. Recent psychological experiments in the army reveal, again, certain fundamental intellectual inferiorities of negroes, though whether this is environmental or to be traced to hereditary causes is open to question.

The fact remains that there are, despite the lack of evidence for hereditary mental differences, practical differences in the mental activity of different races that are of social importance.

These differences, which seem so fundamental, have been explained primarily by the powerful control exercised over the individual by the habits which he acquires even before the age of five years. These, though unconscious, may be, as the Freudian psychologists maintain, all the more important for that reason. This would appear to be the only explanation of significant racial differences. Cultural differences cannot, biologists are generally agreed, be transmitted in the germs that pa.s.s from generation to generation. One may say, in effect, that an individual is differentiated in his mental traits by early a.s.sociation with a certain race, and by his immediate ancestry or family, rather than by the fact of belonging physically to a certain race.

THE INFLUENCE OF IMMEDIATE ANCESTRY OR FAMILY. A factor that is, on experimental evidence, rated to be of high importance in the determination of the differences of the mental make-up of human beings, is "immediate ancestry" or family.

Stated in the most simple and general terms this means that children of the same parents tend to display marked likenesses in mental traits, and to exhibit less variation among themselves than is exhibited in the same number of individuals chosen at random. A great number of experiments have been conducted to determine how far resemblances in mental traits are due to common parentage. The correlation between membership in the same family and resemblances of social traits has been found to be uniformly high.

The inference was made that children of the same family would show great resemblances in mental traits, when accurate experiments showed marked similarity in physical traits under the same conditions. The coefficient of correlation between brothers in the color of the eye, is, according to the results obtained by Karl Pearson, .52.[1] The coefficient of fraternal correlation in the case of the cephalic index (ratio of width to length of head) is .40. The correlation of hair color is found to be .55. The fact of high correlation between resemblance of physical traits and membership in the same family is of crucial importance, because these traits are clearly due to ancestry, and not to environmental differences. If physical traits show such a correlation, it is likely that mental traits will also, mental traits being ultimately dependent on the brain and the nervous system, which are both affected by ancestry.

[Footnote 1: These facts are based on the reports of Karl Pearson in his _On the Laws of Inheritance in Man_. What is meant by coefficient of correlation may be explained as follows: If the coefficient of correlation between father and son is .3 and the coefficient of correlation between brother and brother is .5 we may say: a son on the average deviates from the general trend of the population by .3 of the amount of his father's deviation, a brother by .5 of the amount of his brother.]

Measurements of measurable traits and observations of less objectively measurable ones, have revealed that immediate ancestry is in itself an influential factor in producing likenesses and differences among men with respect to mental traits.

One interesting case, interesting because it was a test of a capacity that might be expected to be largely environmental in its origins, was that of the spelling abilities of children in the St. Xavier School in New York. Thorndike thus reports the test:

As the children of this school commonly enter at a very early age, and as the staff and the methods of teaching remain very constant, we have in the case of the 180 brothers and sisters included in the 600 children closely similar school training. Mr. Earle measured the ability of any individual by his deviation from the average for his grade and s.e.x, and found the co-efficient of correlation between children of the same family to be .50. That is, any individual is on the average fifty per cent as much above or below the average for his age and s.e.x as his brother or sister.

Similarities in home training might theoretically account for this, but any one experienced in teaching will hesitate to attribute much efficacy to such similarities. Bad spellers remain bad spellers though their teachers change. Moreover, Dr. J. M. Rice in his exhaustive study of spelling ability found little or no relationship between good spelling and any one of the popular methods, and little or none between poor spelling and foreign parentage. Yet the training of a home where parents do not read or spell the language well must be a home of relatively poor training for spelling. Cornman's more careful study of spelling supports the view that ability to spell is little influenced by such differences in school or home training as commonly exist.[1]

[Footnote 1: Thorndike: _loc. cit._, p. 78.]

In general the influence of heredity may be said far to outweigh the influence of home training. In all the cases reported, the resemblances were about the same in traits subject to training, and in those not subject to training. Thus industry and conscientiousness and public spirit, which are clearly affected by environment, show no greater resemblance than such practically unmodifiable traits as memory, original sensitiveness to colors, sounds, and distances.

The influence of parentage, it must be added, consists in the transmission of specific traits, not of a certain "nature" as a whole. There are in the germ and the ovum which const.i.tute the inheritance of each individual, certain determinant elements.

The elements that determine the original traits with which each individual will be born vary, of course, in the germs produced by a single parent less than among individuals chosen at random, but they vary none the less. In this variation of the determining elements in the germs of the same individual is to be found the cause of the variation in the physical and mental traits among children of the same parents.

Since the determining elements, the unit characters that appear in the sperm or ovum of each individual, do not appear uniformly even in children of the same parents, brother and sister may resemble each other in certain mental traits, and differ in others. "A pair of twins may be indistinguishable in eye color and stature, but be notably different in hair color and tests of intellect."

Mental inheritance, as well as physical, is, then, organized in detail. It is not the inheritance of gross total natures, but of particular "mental traits." If we had sufficient data, we should be able to a.n.a.lyze out the unit characters of an individual's mental equipment, so as to be able to predict with some accuracy the mental inheritance of the children of any two parents. In the case of physical inheritance, the laws of the hereditary transmission of any given traits are known in considerable detail. The detailed quant.i.tative investigations of inheritance, following the general lines set by Mendel, have given striking results.

Physical traits have been found to be a.n.a.lyzable into unit-characters (that is, traits hereditarily transmitted as units), such as "curliness of hair," "blue eyes," and the like. Mental traits, however, do not seem a.n.a.lyzable into the fixed unit-characters prescribed by the Mendelian laws of inheritance.

The success which breeders have had in the control of the reproduction of plants and animals, in the perpetuation of a stock of desirable characteristics and the elimination of the undesirable, has given rise to a somewhat a.n.a.logous ideal in human reproduction. That eugenics has at least its theoretical possibilities with regard to physical traits, few biologists will question. However difficult it may be in practice to regulate human matings on the exclusive basis of the kind of offspring desired, it is a genuine biological possibility. In a negative way, it has already in part been initiated in the prevention of the marriage of some extreme types of the physically unfit, by the so-called eugenic marriage laws in some states in this country.[1]

[Footnote 1: There have been laws, as there is a fairly decided public opinion, adverse to reproduction by the feeble-minded and the morally defective. But (see Richardson: _The Etiology of Arrested Mental Development_, p. 9) there have been a number of cases of feeble-minded parents producing normal children.]

But whether scientific regulation of marriages for the production of eugenic offspring is feasible, even apart from the personal and emotional questions involved, is open to question.

No mental trait such as vivacity, musical ability, mathematical talent, or artistic sense, has been a.n.a.lyzed into such definitely transmissible unit-characters as "blue eyes"

and "curliness of hair." So many unit-characters seem to be involved in any single mental trait that it will be long before a complete a.n.a.lysis of the hereditary invariable determinants of any single trait can be made.

It is thus impossible to tell as yet with any security or precision the biological components of any single mental trait.

The evidence at our disposal, however, does confirm us in the belief that one of the most significant and certain causes of individual differences, whether physical or mental, is immediate ancestry or family. Individuals are made by what they are initially, and, as we shall presently see, therefore largely by their inheritance. With the latter, environment can do just so much, and no more. And the most significant and effective part of an individual's inheritance is his family for some generations back, rather than the race to which he belongs.

THE INFLUENCE OF THE ENVIRONMENT. Those factors so far discussed which determine individual differences are independent of the particular conditions of life in which an individual happens to be placed. An individual's race, s.e.x, family are beyond modification by anything that happens to him after birth. Maturity, in so far as it is mere growth independent of training, is also largely a fixed and unmodifiable condition.

The original nature, determined by race, s.e.x, and immediate ancestry, with which a man starts life is subject to modification by his social environment, by the ideas, customs, companions, beliefs, by which he is surrounded, and with which he comes continuously in contact. Commonly the influence of environment is held to be very high. It is difficult, however, accurately to distinguish between effects which are due to original nature and effects which are due to environment.

Differences in training are important, but the results vary with the natures trained. Precisely the same environment will not have the same consequences for two different natures.

Two approximately same natures will show something like the same effects in dissimilar environments. Human beings are certainly differentiated by the customs, laws, ideals, friends, and occupations to which they are exposed. But what the net result will be in a specific case, depends on the individual's equipment to start with, an equipment that is fixed before the environment has had a chance to act at all.

The kindliness and indulgence that save some children demoralize others. In some people a soft answer turneth away wrath; in others it will kindle it. Andrew Carnegie starts as a bobbin boy, and becomes a millionaire; but there were many other bobbin boys. The sunset that stirs in one man a lyric, leaves another cold. The same course in biology arouses in one student a pa.s.sion for a life of science; it leaves another hoping never to see a microscope again. On the other hand, the same types of original capacity thrown into different environments will yet attain somewhat comparable results, in the way of character and achievement. The biographies of a few poets, painters, philosophers, and scientists chosen at random, show the most diverse antecedents.[1]

[Footnote 1: Taking the social and professional status of a distinguished man's father as some index of the social environment to which he was subjected during his youth, we find some interesting examples: The father of John Keats was a livery stable-keep; his mother the daughter of one. Byron's father was a captain in the Royal Guards; his mother a Scottish heiress.

Newton's father was a tanner; Pasteur's, a tanner; Darwin's, a doctor of considerable means. Francis Bacon's father was Lord Keeper of the Great Seal; Newton's was a farmer and the headmaster of a school; Turner was the son of a barber.]

An individual, again, to a certain extent, makes his own environment. What kind of an environment he will make depends on the kinds of capacities and interests he has to start with. Similarity of original tendencies and interests brings men together as differences among these keep them apart. The libraries, the theaters, and the baseball parks are all equally possible and accessible features of their environment to individuals of a given economic or social cla.s.s.

Yet a hundred individuals with the same education and social opportunities will make themselves by choice a hundred different environments. They will select, even from the same physical environment, different aspects. The Grand Canon is a different environment to the artist and to the geologist; a crowd of people at an amus.e.m.e.nt park const.i.tutes a different environment to the man who has come out to make psychological observations, and the man who has come out for a day's fun. A dozen men, teachers and students, selected at random on a university campus, might well be expected to note largely different though overlapping facts, as the most significant features of the life of the university.

The environment is the less important in the moulding of character, the less fixed and unavoidable it becomes. If an individual has the chance to change his environment to suit his own original demands and interests, these are the less likely to undergo modification. This is ill.u.s.trated in the animal world by the migratory birds, which change their habitations with the seasons. Similarly human beings, to suit the original mental traits with which they are endowed, can and do exchange one environment for another. There are a very large number of individuals living in New York City, in the twentieth century, for example, for whom a multiplicity of environments are possible. The one that becomes habitual with an individual is a matter of his own free choice. That is, it is choice, in the sense that it is independent of the circ.u.mstances of the individual's life. But an individual's choice of his environment must be within the limited number of alternatives made possible by the original nature with which he is endowed. As pointed out in connection with our discussion of "Instinctive Behavior," we do originally what gives satisfaction to our native impulses, and avoid what irritates and frustrates them. We may be trained to find satisfactions in acquired activities, but there is a strong tendency to acquire habits that "chime in," as it were, with the tendencies we have to start with.

There is, for example, to certain individuals, intrinsic satisfaction in form and color; to others in sound. To the former, pictures and paintings will tend to be the environment selected; to the latter the hearing and the playing of music. To those gifted with sensitivity in neither of these directions, pictures may be through all their lives a bore, and a piano a positive nuisance.

These facts of original nature, therefore, determine initially, and consequently in large part, what our environment is going to be. Once we get into, or select through instinctive desires, a certain kind of environment, those desires become strengthened through habit, and that environment becomes fixed through fulfilling those habitual desires. A man may, in the first place, choose artists or scholars as companions because his own gifts and interests are similar. But such an environment will become the more indispensable for him when it has the reinforcement of habit to confirm what is already initially strong in him by birth. "To him who hath shall be given" is most distinctly true of the opportunities and environment open to those with native gifts to begin with.

Original nature thus sets the scope and the limits of an individual's character and achievement. It tells "how much" and, in the most general way, "what" his capacities are. Thus a man born with a normal vocal apparatus can speak; a man born with normal vision can see. But what language he shall speak, and what sights he shall see, depend on the social and geographical situation in which he happens to be placed. Again, if a man is born with a "high general intelligence," that is, with keen sensory discriminations and motor responses, precise and accurate powers of a.n.a.lysis of judgment, a capacity for the quick and effective acquisition and modification of habits, we can safely predict that he will excel in some direction. But whether he will stand out as a lawyer, doctor, philosopher, poet, or executive, it is almost impossible from original nature to tell.[1]

[Footnote 1: The psychological tests used in the army, and being used now with modifications in the admission of students to Columbia College, are "general intelligence" tests. That is, they show general alertness and intellectual promise, but are not prophetic of any specialized talents or capacities.]

INDIVIDUAL DIFFERENCES--DEMOCRACY AND EDUCATION. The fact that individuals differ in ability and interest has important consequences for education and social progress. It means, in the first place, that while current optimistic doctrines about the modifiability of human nature are true, they are true within limits--limits that vary with the individual.

Whether or not we shall ever succeed, through the science or the practice of eugenics, in eliminating low ability and perpetuating high exclusively, the fact remains that there are in contemporary society the widest variations both in the kinds of interest and ability displayed, and in their relative efficacy under present social and industrial conditions.

There are, it must be noted at the outset, a not inconsiderable number of individuals who must be set down as absolute social liabilities. Even if existing social and educational arrangements were perfect, these would remain unaffected and unavailable for any useful purpose. They would have to be endowed, cared for, or confined. There is the quite considerable cla.s.s, who, while normal with respect to sensory and motor discrimination, seem to be seriously and irremediably defective in their powers of judgment. These also seem to offer invulnerable resistance to education, and their original natures would not be subject to modification even by an education perfectly adapted to the needs of normal people.

But the more significant fact, more significant because it affects so many, is the fact that within the ranks of the great cla.s.s of normal people, there are fundamental inherited differences in ability and interest. Next in importance to the fact that an individual is human is the fact that he is an individual, with very specific initial capacities and desires. For education the implications are serious. Education aims, among other things, to give the individual habits that will enable him to deal most effectively with his environment. But an individual can be trained best, it goes without saying, in the capacities and interests he has to begin with. Education cannot, therefore, be wholesale in its methods. It must be so adjusted as to utilize and make the most of the multifarious variety of native abilities and interests which individuals display. If it does not utilize these, and instead sets up arbitrary moulds to which individuals must conform, it will be crushing and distorting the specific native activities which are the only raw material it has to work upon.

There have not as yet been many detailed quant.i.tative studies of individual differences that would enable educators, if they were free to do so, scientifically to adapt education to specific needs and possibilities. Beginnings in this direction are being made, though rather in advanced than in more elementary education. Professional and trade schools, and group-electives in college courses are attempts in this direction.

Any attempt, of course, to adapt education to specific needs and interests, instead of crushing them into _a priori_ moulds, requires, of course, a wider social recognition and support of education than is at present common. For individual differences require attention. And where millions are to be educated, individual attention requires an immense investment in teaching personnel.