The Story of Psychology (41 page)

Galton felt certain that in a “progressive” society (his term) such as Victorian England, innate ability was sure to be rewarded by success: “If a man is gifted with vast intellectual ability, eagerness to work, and power of working, I cannot comprehend how such a man should be repressed… [Rather,] he is sure to be welcomed with universal acclamation.”
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Heroic labor at his genealogical research yielded Galton the finding that of the 286 judges in his sample, about one in nine was the father, son, or brother of another judge; in addition, the judges numbered among their relatives many bishops, admirals, generals, novelists, poets, and physicians. The incidence of eminence in these families was hundreds of times greater than in the general population; the same was true of the other categories of eminent persons.

Summing up the data for all his categories of illustrious people, he reported that 31 percent had eminent fathers, 41 percent eminent brothers, and 48 percent eminent sons. Moreover, the closer the relationship between an eminent person and a relative, the greater the likelihood that the relative was eminent. Galton was satisfied that he had thoroughly proved his hypothesis—“that a man’s natural abilities are derived from inheritance, under exactly the same limitations as are the form and physical features of the whole organic world.”
⁸

Contemporary psychologists can point to a number of naïve shortcomings in Galton’s methodology, in particular his failure to evaluate the environments in which the illustrious grew up; if most of them had been reared in strongly favorable circumstances, the data might point to environmental influence as much as to hereditary influence. But whatever the limitations of Galton’s technique, he had established the hereditary aspect of intelligence as a valid subject for psychological research, and it has remained so ever since.

Galton’s name, however, has been tarnished by the recommendations for social policy that he based on his findings and by the meanings history has given to them. It was he who coined the term “eugenics” and
who argued, from his first book about hereditary genius in 1869 until his death in 1911, that society would be improved if it encouraged and rewarded the breeding of superior people:

This view came to seem horrendous in the wake of Nazi efforts to encourage the procreation of pure “Aryans” and to exterminate Jews, Gypsies, and other groups they considered human vermin. Galton himself, according to his biographers, seemed a gentle and decent human being, and certainly not an advocate of genocide, but some of his comments about the proper treatment of undesirable people tread close to the line:

One might expect a man with such views to have been a racist who saw all human groups other than his own as subhuman, but Galton was not. Although he estimated the average intelligence of blacks as two levels below the English, he rated the English as two levels below the ancient Athenians; he also said that he would have liked to investigate Italians and Jews, “both of whom appear to be rich in families of high intellectual breeds.”

While Galton’s ideas about eugenics are no part of present-day psychology, they led him to invent some of the field’s most valuable methods of research. The genealogical study of the inheritability of psychological traits is only one of them. Another and even more useful one was inspired by criticisms of
Hereditary Genius
that pointed to evidence of the influence of environment on intelligence, particularly the statistical
findings of the Swiss botanist Alphonse de Candolle, showing that great scientists tend to come from countries with moderate climates, religious tolerance, democratic government, and healthy commercial interests— all environmental influences.

This spurred Galton on to an effort to distinguish the influences of heredity and environment in the achievement of eminence, specifically in science. In 1874, in
English Men of Science
, he stated the problem very fairly, using a shorthand expression for genetic and environmental influences on development that immediately entered the language:

To learn about the part played by nature and by nurture in scientific eminence, Galton invented another new research tool: the self-questionnaire. He drew up a set of questions about the respondent’s racial, religious, social, and political background, traits of character, and even hair color and hat size, and sent copies to two hundred members of the Royal Society. Among the crucial questions were: “How far do your scientific tastes appear to have been innate? Were they largely determined by events after you reached manhood, and by what events?”

Despite the questionnaire’s “alarming” length—Galton’s own rueful term—most of the subjects completed and returned it. (It was the first such questionnaire in history; today a researcher might get no such compliance.) When Galton tabulated the responses, he found that a majority believed their taste for science was innate; on the other hand, most respondents had a lot to say about how their education had either helped or hindered them. Galton felt obliged to admit that environmental factors, education in particular, could enhance or inhibit the development of scientific aptitude, and that its inheritance did not inevitably lead to success. Nonetheless, he maintained that hereditary aptitude had been shown to be the essential factor in scientific achievement.

Much later, as research methodology developed, it would become
apparent that Galton’s questionnaire and his analysis of the data had serious weaknesses. For one thing, many of the questions, particularly those about the reasons for the respondents’ success, yielded purely subjective answers; for another, Galton had not given the questionnaire to noneminent scientists and nonscientists to see whether their answers were any different from those of eminent scientists; for a third, he had no way (though later he would invent one) to mathematically measure the relation between any two factors so as to judge whether it was accidental or significant. All the same, Galton’s use of the questionnaire and analysis of the data were innovations of immense value and have been important weapons in the armamentarium of psychological research ever since.

During the next decade Galton, now middle-aged, worked harder than ever at studies of individual psychological differences. In 1883 he published his observations on some thirty miscellaneous topics in an
omnium gatherum
titled
Inquiries into Human Faculty and Its Development
, a curious mixture of science and speculation, data and conjecture, statistics and anecdotes. Some of it purported to be science but was little more than Victorian male prejudice. In the chapter on “character,” for instance, Galton asserted without offering evidence that “one notable peculiarity in the character of the woman is that she is capricious and coy, and has less straightforwardness than the man.” He approved of this on evolutionary grounds: in courtship, were there no female hesitancy and male competition, “the race would degenerate through the absence of that sexual selection for which the protracted preliminaries of love-making give opportunity.”

But a good deal of
Inquiries
consisted of highly original scientific studies. One dealt with the ability to summon up mental images. Many nonscientists, Galton found, think in vivid images, many scientists in purely abstract terms, and he speculated that the ability to summon up sharp mental images hinders thinking in highly generalized and abstract terms. In another study he reported his invention of the word-association test; he drew up a list of seventy-five stimulus words and exposed them to his own view one by one, jotting down his first two or three associations to each. Most of what he learned was unremarkable, such as that, on repeating the test, he came up with the same associations. But there was genuine value to his observation that many of his
associations sprang from his own experiences and that other people would be unlikely to have his associations. The result was that word-association tests became a leading way of studying individual personality traits.

Another noteworthy study was a report of one more Galton innovation. Still grappling with the problem of how to demonstrate the relative influences of nature and nurture on the development of the mind and personality, he had the brilliant idea of examining “the after-history of those twins who had been closely alike as children, and were afterwards parted, or who had been originally unlike and afterwards reared together.” He knew that twins came in two kinds: those who were physically almost identical and those who were no more alike than any other two siblings. If twins who were originally very similar became less so as they went through life, it could only be nurture that made them so; if twins who were originally dissimilar and were reared identically remained dissimilar, it could only be nature that kept them so.

It was a dazzling hypothesis, though Galton had only crude means of proving it. He sent a questionnaire to twins or relatives of twins he knew; he also asked them to give him the names of other twins. Eventually he had replies from ninety-four cases, eighty of which were of “close similarity” (probably identicals) and thirty-five of which provided enough details to be useful.

His report of the twin study is largely anecdotal; it tells of identicals who played tricks on people, or were both paddled by a schoolmaster who could not tell which one deserved punishment, of one who sometimes courted his brother’s fiancée, and so on. But when Galton sorted through his cases in search of identicals who became dissimilar in character, he found that, for some, “the resemblance of body and mind continued unaltered up to old age, notwithstanding very different conditions of life.” Others did exhibit differences, but in every case it was because an illness or accident had affected only one of the pair. In contrast, twins who had been dissimilar in childhood (probably fraternals), even if reared together and identically, did not become more alike over the years.
¹²

Not one given to caution, Galton proclaimed, “There is no escape from the conclusion that nature prevails enormously over nurture when the differences of nurture do not exceed what is commonly to be found among persons of the same rank of society and in the same country.” From a contemporary perspective, the study was simplistic, imprecise,
and far from conclusive. Still, it was a notable first, and the twin study method has been an important research strategy ever since and the most nearly definitive way of assessing the influences of heredity and environment on intelligence, personality traits, and other psychological characteristics.

Finally, Galton discussed in
Inquiries
his development of a number of mental tests in order quickly and simply to identify persons of superior intelligence, as part of his grand dream of improving the human race through eugenics. The year after
Inquiries
appeared, he began his trials of the tests at the International Health Exhibition, and when the fair closed down, he got permission from the South Kensington Museum to continue operating the laboratory there for a number of years. During that time he devised a number of new mental tests, among them a bar with a variable distance on it to test the ability to estimate extension, a rotating disk to test the ability to judge perpendicularity, sets of weights to be arranged in order of heaviness, and sets of bottles that contained aromatic material to be arranged according to intensity of odor.
¹³

Galton was in his late sixties, far beyond the age at which scientists usually make their important discoveries, when he made his most important one. Appropriately, it involved his lifelong obsession, counting. Each kind of measurement made in the Anthropometric Laboratory had yielded a bell-shaped probability curve, but Galton sensed that he might glean other and highly significant information if he could discover how the different sets of measurements were related to one another. Some of the relationships were obvious—taller people, for instance, tended to weigh more—but what was the relationship between other sets of measurements? Which of them varied together and in the same degree? What did it mean if they did not vary in the same degree? Only by knowing how the data were related and which measures had little connection with the others would he be able to design an ideal battery of tests indicative of intelligence.

Galton had been led to consider this problem by an odd finding in his studies of hereditary genius: the children of unusual parents were generally less unusual. In terms of physical traits, for instance, the children of tall parents tended to be less tall, though still above average, and the children of short parents not as short, though still below average, a tendency Galton called “regression towards mediocrity” (later, the term became “regression towards the mean”). He wanted to know what it indicated about the strength of heredity and how he could express it
mathematically. On the face of it, this seemed a purely intellectual puzzle; as it turned out, the solution to the problem would become one of the most useful research tools in psychology and many other sciences.