Raising Cognitive Ability - Living Together - The Bell Curve: Intelligence and Class Structure in American Life - Richard J. Herrnstein, Charles Murray

The Bell Curve: Intelligence and Class Structure in American Life - Richard J. Herrnstein, Charles Murray (1996)

Part IV. Living Together

Our analysis provides few clear and decisive solutions to the major domestic issues of the day. But, at the same time, there is no major domestic issue for which the news we bring is irrelevant.

Do we want to persuade poor single teenagers not to have babies? The knowledge that 95 percent of poor teenage women who have babies are also below average in intelligence should prompt skepticism about strategies that rely on abstract and far-sighted calculations of self-interest. Do we favor job training programs for chronically unemployed men? Any program is going to fail unless it is designed for a target population half of which has IQs below 80. Do we wish to reduce income inequality? If so, we need to understand how the market for cognitive ability drives the process. Do we aspire to a “world class” educational system for America? Before deciding what is wrong with the current system, we had better think hard about how cognitive ability and education are linked. Part IV tries to lay out some of these connections.

Chapter 17 summarizes what we know about direct efforts to increase cognitive ability by altering the social and physical environment in which people develop and live. Such efforts may succeed eventually, but so far the record is spotty.

Chapter 18 reviews the American educational experience of the past few decades. It has been more successful with the average and below-average student than many people think, we conclude, but has neglected the gifted minority who will greatly affect how well America does in the twenty-first century.

In Chapters 19 and 20, the focus shifts to affirmative action policies in education and in the workplace. Our society has dedicated itself to coping with a particular sort of inequality, trying to equalize outcomes for various groups. The country has retreated from older principles of individual equality before the law and has adopted policies that treat people as members of groups. Our contribution (we hope) is to calibrate the policy choices associated with affirmative action, to make costs and benefits clearer than they usually are.

The final two chapters look to the future. In Chapter 21, we sound a tocsin. Predictions are always chancy, and ours are especially glum, but we think that cognitive stratification may be taking the country down dangerous paths. Chapter 22 follows up with our conception of a liberal and just society, in light of the story that the rest of the book has told. The result is a personal statement of how we believe America can face up to inequality in the 21st century and remain uniquely America.

Chapter 17. Raising Cognitive Ability

Raising intelligence significantly, consistently, and affordably would circumvent many of the problems that we have described. Furthermore, the needed environmental improvements—better nutrition, stimulating environments for preschool children, good schools thereafter—seem obvious. But raising intelligence is not easy.

Nutrition may offer one of the more promising approaches. Height and weight have increased markedly with better nutrition. The rising IQs in many countries suggest that better nutrition may be increasing intelligence too. Controlled studies have made some progress in uncovering a link between improved nutrition and elevated cognitive ability as well, but it remains unproved and not well understood.

Formal schooling offers little hope of narrowing cognitive inequality on a large scale in developed countries, because so much of its potential contribution has already been realized with the advent of universal twelve-year systems. Special programs to improve intelligence within the school have had minor and probably temporary effects on intelligence. There is more to be gained from educational research to find new methods of instruction than from more interventions of the type already tried.

Preschool has borne many of the recent hopes for improving intelligence. However, Head Start, the largest program, does not improve cognitive functioning. More intensive, hence more costly, preschool programs may raise intelligence, but both the size and the reality of the improvements are in dispute.

The one intervention that works consistently is adoption at birth from a bad family environment to a good one. The average gains in childhood IQ associated with adoption are in the region of six points—not spectacular but not negligible either.

Taken together, the story of attempts to raise intelligence is one of high hopes, flamboyant claims, and disappointing results. For the foreseeable future, the problems of low cognitive ability are not going to be solved by outside interventions to make children smarter.

Can people become smarter if they are given the right kind of help? If raising intelligence is possible, then the material in Parts II and III constitutes a clarion call for programs to do so. Social problems are highly concentrated among people at the bottom of the cognitive distribution; those problems become much less prevalent as IQ increases even modestly; and the history of increases in IQ suggests that they occur most readily at the bottom of the distribution. Why not mount a major national effort to produce such increases? It does not appear on its face to be an impossible task. Even the highest estimates of heritability leave 20 to 30 percent of cognitive ability to be shaped by the environment. Some researchers continue to argue that the right proportion is 50 to 60 percent. In either case, eliminating the disadvantages that afflict people in poor surroundings should increase their cognitive functioning.1

Upon first consideration, the ways to eliminate those disadvantages seem obvious. Many children of low-income parents grow up in terrible home environments, with little stimulation or nurturing. Surely, it would seem, intelligence would rise if these children were placed in day care environments where professionals provided that stimulation and nurturing. Schools in poor neighborhoods are often run down and chaotic. Isn’t it clear that increasing the investment in schools would pay off in higher scores?

Limitless possibilities for improving intelligence environmentally wait to be uncovered by science: improved educational methods, diets, treatments for disease, prenatal care, educational media, and even medicines to make one smarter. In principle, intelligence can be raised environmentally to unknown limits.

Yet the more one knows about the evidence, the harder it is to be optimistic about prospects in the near future for raising the scores of the people who are most disadvantaged by their low scores. For one thing, it is hard to find new ways to use existing resources that are not already being done. The nurturing of the young—including the cognitive nurturing—is one of the central purposes of human society. That, after all, is what families mainly do. Very high proportions of children already get prenatal care, nutrition, home environments, and classroom environments that are good enough to leave little room for measurable improvement. The grim stories about childhood deprivation involve a small proportion of children. And when it comes to helping that small proportion of children, the results seldom approach expectations. We may be deeply and properly dissatisfied with the nurturing of American intelligence, but finding solutions that are affordable, politically tolerable, and not already being tried is another matter altogether.

In this chapter, we move through a succession of topics. First we consider the effects of nutrition. We then discuss a sequence of successively more targeted, intense social interventions: education in general, preschool interventions, intensive support for children at risk for retardation, and the most extreme form of social intervention, adoption at birth. We close with our thoughts on what society’s experiences with these interventions should mean for policy in the future.


Most of us have been urged by a parent or grandparent to eat the “brain food,” which seemed invariably to be the most unpalatable thing on the table. This idea of a connection between diet and intelligence has an ancient history going back to mens sana in corpore sano.2 In the twentieth century, the plausibility of a connection has been reinforced by the fact that people in affluent countries are larger than their ancestors were, presumably in part because they are eating better. IQ scores, too, have been rising during approximately the same period—the Flynn effect described in Chapter 13. These coincident changes do not prove that better eating makes for smarter people, but count as circumstantial evidence.

For a while, however, scientific research seemed to have weakened the case for any link between nutrition and IQ. The most damaging blow was a study of over 100,000 Dutch men who were born around a time of intense famine in several Dutch cities near the end of World War II.3 Nineteen years later, the men took intelligence tests as part of the qualification for national military service, and it occurred to scholars to compare the ones who were born in the depths of the famine to those born just before and just after it. Many pregnant women miscarried during the famine, but their surviving sons scored no lower in intelligence than the men born to mothers who had little or no exposure to famine. But as important as this study was, some scientists were not entirely convinced by its negative findings. The Dutch famine was relatively brief—three months or so—and limited to the pre- and perinatal period of the men’s lives. And while the mothers were indeed starving for calories, their deficiencies in vitamins, minerals, and other dietary elements were perhaps too brief to take a toll.4

Another approach to the impact of nutrition on cognitive ability is to see whether enriched diets can raise scores. A breakthrough study done in Great Britain in the late 1980s concluded that the answer was yes.5 David Benton and Gwilym Roberts gave a sample of thirty Welsh 12- to 13-year-old children vitamin and mineral supplements for eight months and compared their test scores with an equal number of their schoolmates getting nonnutritive placebos. The Welsh children were not known to be malnourished, but those getting the supplement gained eight points more in their nonverbal intelligence test scores than those getting the placebo, a large and statistically significant improvement. Verbal scores showed no differential improvement.6

A recent American confirmation of the Welsh results gave over 600 eighth and tenth graders in several California schools daily pills for thirteen weeks.7 The pills contained either half the recommended daily allowances (RDA) of a wide assortment of vitamins and minerals, precisely the RDA, twice the RDA, or a placebo. The vitamin and mineral supplement raised scores on most of the nonverbal sub tests of a standard intelligence test.8 The verbal intelligence test scores again failed to register any benefit, but that is consistent with the Flynn effect: The rising average intelligence scores of nations seem primarily to be on non-verbal tests.

The net average benefit for pills providing one RDA was about four points in nonverbal intelligence in the California study. But this average gain comprised many youngsters who did not benefit at all, mixed with some whose gains exceeded fifteen points. The children who did not benefit were presumably already getting the vitamins and minerals they needed for developing their nonverbal scores in their regular diets. But this is just a hypothesis at present. It remains to be shown whether the gain from vitamins or minerals can be associated with preexisting food deficiencies, let alone which particular dietary ingredients, in what amounts, produce the gains.9 Youngsters getting exactly the RDA had the largest gain in scores; those taking either more or less of the supplement benefited less, if at all10 This is not only puzzling but worrisome. Could it rhean that excessive dosages of vitamins and/or minerals harm intellectual functioning? There is no evidence that it does, but at the least, it reinforces the prudence of doing more research before going overboard for vitamin and mineral supplements.

Other Physiological Influences on IQ. Or Are They? Two Further Examples

The physiological environment seems to be associated with IQ in other ways. For example, some studies (hut not all) have found a small decline in IQ of each successive child born to a given woman, even after holding overall family size constant.12 Is this a matter of the social environment within the family, which changes as new children enter it, or the physiological environment in the uterus, which is both older on average and has a longer history of childbirth with each successive pregnancy? The answer is unclear, and both views have been advanced. But, whichever it is, this would be a genuine environmental effect on intelligence, since the rolls of the genetic dice for the successive offspring of a given mother and father are independent as far as anyone knows.

Another environmental and possibly physiological influence on IQ is suggested by data from twins. Among identical twins, the one with the higher IQ is likely to have been heavier at birth.13 This is part of a more general finding that higher weights at birth are associated with higher IQs in childhood, but the identical twin data decisively prove that the correlation between birth weight and later intelligence has an environmental element, since identical twins are genetic clones.14 It is less certain that there are no social factors here: People may treat twin babies differently if one is plumper than the other. Training mothers in how to be more attentive to their low-birth-weight babies seems, in fact, to raise later IQ, at least up to the age of 7.15

This caution is reinforced by the inconsistency of the nutritional effect on IQ. Many studies that seem to be well-conducted variations of the successful ones have failed to demonstrate any effect on IQ at all.11 The reasonable middle ground at this point is to conclude that providing children with the recommended daily allowance of vitamins is a good idea for many reasons and might also have a helpful effect on IQ.


The almost reflexive reaction of most people when they hear about the below-average test scores among children in the bottom of the socioeconomic distribution is that of course they have low scores because they have gotten poor educations. Improve the schools, it is assumed, and the scores will rise.

There are a number of problems with this assumption. One basic error is to assume that new educational opportunities that successfully raise the average will also reduce differences in cognitive ability. Consider trying to raise the cognitive level by putting a public library in a community that does not have one. Adding the library could increase the average intellectual level, but it may also spread out the range of scores by adding points to the IQs of the library users, who are likely to have been at the upper end of the distribution to begin with. The literature on such “aptitude-treatment interactions” is large and complex.16 For example, providing computer assistance to a group of elementary school children learning arithmetic increased the gap between good and bad students;17 a similar effect was observed when computers were used to teach reading;18 the educational television program, “Sesame Street” increased the gap in academic performances between children from high- and low-status homes.19 These results do not mean that such interventions are useless for the students at the bottom, but one must be careful to understand what is and is not being improved: The performance of those at the bottom might improve, but they could end up even further behind their brighter classmates.

A second broad difficulty with relying on improvements in education is that although they make some difference in IQ, the size of the effect is small. This conclusion is supported by evidence from both natural variation in education and planned educational experiments.

Looking at Natural Variation

Parents buying new houses often pick the neighborhood according to the reputation of the local schools. Affluent parents may spend tens of thousands of dollars to put their children through private schools. Tell parents that the quality of the schools doesn’t matter, and they will unanimously, and rightly, ignore you, for differences in schools do matter in many important ways. But in affecting IQ, they do not matter nearly as much as most people think.

This conclusion was first and most famously reached by a study that was expected to demonstrate just the opposite. The study arose out of a mandate of the Civil Rights Act of 1964 to examine how minority groups are affected by educational inequalities. The result was a huge national survey, with a sample that eventually numbered 645,000 students, led by the eminent sociologist James S. Coleman. His researchers measured school quality by such objective variables as credentials of the teachers, educational expenditures per pupil, and the age and quality of school facilities.

Because the schools that most minority children attended were measurably subpar in facilities and staff, it was assumed that the minority children fortunate enough to attend better schools would also show improved cognitive functioning. But the report, issued in July 1966, announced that it had failed to find any benefit to the cognitive abilities of children in public primary or secondary schools that could be credited to better school quality.20 The usual ways in which schools tried to improve their effectiveness were not likely to reduce the cognitive differences among individual children or those between ethnic groups.

The Coleman report’s gloomy conclusions were moderated in subsequent analyses that found some evidence for marginal benefits of school quality on intellectual development.21 Coleman himself later concluded that parochial schools generally do a better job of developing the cognitive abilities of their students than public schools, which pointed to at least some factor in schooling that might be exploited to improve intelligence.22 Yet the basic conclusion of the report has stood the test of time and criticism: Variations in teacher credentials, per pupil expenditures, and the other objective factors in public schools do not account for much of the variation in the cognitive abilities of American school children.23

The several hundred thousand children assessed in the Coleman study had not been subjects in educational experiments. They were just students in several thousand local schools. The schools varied in quality, as they inevitably will.24 Some schools, usually in prosperous urban or suburban districts, got (and still get) more money, more teachers with better qualifications, newer school buildings, and the like. Poorer or rural districts usually made (and make) do with less. The Coleman report, in other words, is one of a species of educational research that draws on natural variation—variation that is occurring spontaneously rather than by design.

Looking at the effects of natural variation has advantages as a research strategy. One is that this kind of research does not require new investments of time and money to intervene in schools. The intervening has already been done at someone else’s expense. The disadvantage of such studies is that the variation is often narrow—an example of the restriction of range problem that we described in Part I. If almost all classes have, say, between twenty-five and thirty-five children in them, then looking at natural variation cannot reveal what would happen in classes with five or ten children in them. The Coleman report did not prove that educational reform is always futile, but that, on the whole, America had already achieved enough objective equalization in its schools by 1964 so that it was hard to pick up any effects of unequal school quality. The Coleman report tells us that the cognitive ability differences among individuals and groups alike on a national scale cannot be reduced much by further attempts to equalize the kinds of bricks-and-mortar factors and teacher credentials that school boards and taxpayers most often concern themselves with.

Aside from the issue of school quality is the question of whether simply going to school makes any difference to one’s intelligence. The answer is self-evidently yes. Going to school and learning how to read and write, manipulate numbers, find out about one’s culture and about the discoveries of science are going to raise scores on IQ tests compared to not going to school. But although it is obvious that schooling itself fosters intelligence, it is far less obvious how much of the intellectual variation around us can be attributed to differences in the amount of schooling people get. If large numbers of people were getting no schooling at all, there would be cognitive disadvantages on a grand scale that could be blamed on a lack of formal education. But in modern countries, natural variation does not span so wide a range.

An example of a study that had enough natural variation in it to find an effect of schooling was done in Sweden a half-century ago.25 IQ tests were given in 1938 to a representative sample of several hundred 10-year-old boys in public and private schools in a Swedish city. Ten years later, the boys were tested again as part of an induction examination for national military service. In addition to the two IQ scores, the boys’ home and family backgrounds and the total years of schooling were available for analysis.

The average subject in the study had completed only eight years of schooling, which means that many of them had completed fewer. Fewer than 10 percent of them had finished high school, and still fewer had gone on to university. Compared to present-day Sweden or America, the men experienced a wide range of years in school. Even so, the main determiner by far of IQ at the age of 20 was the IQ at the age of 10, by a factor of more than five times as important as years of schooling.26 On the other hand, schooling was a significant though much weaker predictor, after holding IQ at age 10 and family background constant. Since there was some beneficial effect of schooling, the results of the study were properly used to argue that additional years of school would pay off in higher scores.

We can infer from the Swedish study that some of the Flynn effect around the world is explained by the upward equalization of schooling, but a by-product is that schooling in and of itself no longer predicts adult intelligence as strongly, assuming it did so when many people were not getting much schooling.27 The more uniform a country’s schooling is, the more correlated the adult IQ is with childhood IQ.

The average American now gets more than three extra years of schooling compared to the time when the earliest intelligence tests were given. To be sure, years spent in school still varies in America, and it is presumably still contributing to variation in cognitive abilities.28 But given how small the effect was in the Sweden of the 1930s and 1940s, it is unlikely to be large in America today, given the enormous compression of educational variation in America during the twentieth century (see Chapters 1 and 6). Nevertheless, we accept the basic premise that variation in the amount of schooling accounts for some portion of the observed variation in cognitive ability. Besides not knowing how large this remaining effect is, it is hard to estimate how much more would be gained on the average by further equalization of years of schooling. Gains reaped at the bottom of the cognitive ability distribution may be paid for by losses at the top, a process we discuss in the next chapter.

School differences can nonetheless be important. If a child is near the top of the intelligence distribution to begin with, the school can make a major difference in whether that intellectual talent is actually realized, a topic we consider in the next chapter. Or if a child has specific learning disabilities, access to the latest pedagogical techniques and technology may make a major difference. There doubtless are, in addition, pockets in America’s vast educational realm where schools are uncommonly good or uncommonly poor, in which the children are benefiting or suffering cognitively. By definition, however, these are unusual cases, not likely to show up in national data on intelligence.

This discussion has not meant to imply that the fostering of cognitive ability is the only result we want from schools. The civility, let alone the safety, of the environment may vary widely from school to school. Skillful teachers may make learning more interesting. They may infuse children with a love of learning to some extent. These are effects worth worrying about, but they do not alter the fundamental message that the data convey: Equalizing the amount or objective quality of schooling in America cannot be counted on to equalize cognitive ability much.

Compensatory Education

Just a year prior to the Coleman report, the U.S. Congress passed the Elementary and Secondary Education Act (ESEA) of 1965, thereby opening a massive and continuing effort to improve the education of disadvantaged students that continues to this day. In the first fiscal year, grants for educationally deprived children under Title I of the ESEA went from zero to $3 billion, rose to $4 billion in the next year, and have remained there, or higher, ever since. Expenditures in fiscal 1992 were at an all-time high of $5.6 billion (all figures are in 1990 dollars).29

Sponsors of Title I assumed that these programs would narrow the gap in cognitive functioning between disadvantaged children and other students. To prove this, the act also funded an aggressive, ongoing evaluation effort, resulting over the years in a mounting stack of reports. In the mid-1970s, the National Institute of Education (NIE) commissioned a synthesis of the results. Reviewing all the federal studies from 1965 to 1975, researchers found no evidence that students in compensatory education programs closed the gap with their more able peers. Some plausible data suggested that “students in compensatory programs tend to fall behind other students, but not as fast as if they had received no compensatory instructions,” an outcome that the institute treated as evidence of success.30 The greatest support in the various studies was for a simpler “no effect” conclusion: The gap was about as great after compensatory education as before.31 No evidence whatsoever supported a conclusion that compensatory education narrowed the achievement gap.

More optimistically, supporters of compensatory education can call upon the evidence of converging black-white test scores that we described in Chapter 13 as indirect evidence that something positive has been happening in elementary and secondary education for minorities. As we described, improvement has been the largest at the bottom of the IQ distribution, which in turn points toward compensatory programs as a possible cause. But direct evidence of the link remains elusive. In recent years, compensatory programs have set more modest goals, for themselves.32 Now, they focus on teaching specific academic skills or problem solving, not expecting improvements in overall academic achievement or general intelligence.33

Stories Too Good to Be True

Accounts of phenomenal success stories in education—the inner-city school that suddenly excels as the result of a new program or a new teacher—are a perennial fixture of American journalism. Are they true? If the question is whether an inspirational teacher or some new program has the capacity to make an important difference in students’ lives, then the answer is surely yes. But claims for long-term academic improvement, let alone increases in cognitive functioning, typically fade as soon as hard questions begin to be asked. A case in point is Chicago’s Marva Collins, who gained national attention with claims that her shoestring-budget inner-city school, launched in 1975, was turning out students who blew the top off standardized tests and were heading to the best universities. Between the ages of 5 and 10, she claimed, her pupils, deemed “unteachable” in regular schools, were reading Plato, Aristotle, Chaucer, Shakespeare, and Tolstoy, according to stories in the popular media. According to other newspaper reports, she was asked by both Presidents Reagan and Clinton to become secretary of education. She continues to train large numbers of teachers in her methods.34 Are her celebrated anecdotes borne out by data? We do not know. Despite years of publicity about Marva Collins, we can find no hard evidence.35

More generally, the large test score increases in local schools that are widely and routinely reported by the media have been plagued by fraud. In several schools in and around Washington, D.C., for example, the Washington Post reported that gains in test performance were found to be due to improper coaching on the tests by school employees or by allowing extra time for students to complete the tests.36 A story in the Los Angeles Times told of various methods of cheating on standardized tests, including the replacing of wrong answers with right ones by teachers and staff, in at least fifty elementary public schools statewide.37 The New York Times wrote about a public school principal who had been caught tampering with student test scores for years.38 These specific instances seem to be part of a widespread problem.39

Raising IQ Among the School-Aged: Converging Results from Two Divergent Tries

The question remains: Is there any evidence that cognitive ability as measured by IQ tests can be increased by special interventions after children reach school age? We have some reason for thinking the answer is a highly qualified yes, and some basis for estimating how much, from two sources of evidence drawn from strikingly different contexts.

The first is one of the largest controlled experiments attempting explicitly to raise the intelligence of school-age children. It occurred in Venezuela, where in 1979 the incoming president named to his cabinet a Minister of State for the Development of Human Intelligence.40 The new minister was convinced that a nation’s average intellectual level was fundamental to its well-being, and he set out to see what could be done to raise the IQ of Venezuelan school children. The result was Project Intelligence, designed over four years by a team of Venezuelan and American psychologists, educators, and other specialists. In the fifth year, 900 youngsters in seventh grade in a poor district of a Venezuelan provincial city were randomly divided into experimental and control groups.41 Those in the experimental group were taught approximately sixty forty-five-minute lessons in addition to their regular curriculum during the year and were cognitively tested before, during, and after the year. The students in the control group were tested at the same intervals, without receiving any of the additional instruction. The special lessons involved instruction in the kinds of intellectual activities that turn up on intelligence tests—visuospatial and verbal reasoning, vocabulary and word analogies—in addition to lessons in inventive thinking.42 At the end of the year, the youngsters in the experimental group, compared to the controls, had gained a net of more than 0.4 standard deviation on a conventional intelligence test and a net gain of just over 0.1 standard deviation on a culture-fair intelligence test—in other words, a net gain in the range between 1.6 and 6.5 IQ points. There was no chance to see if the gain faded out or was reflected in the rest of the students’ academic performance, nor can we even guess how much a second or third year of lessons would have accomplished.

The second source of evidence comes from the unsystematic but massive attempt to raise intelligence that goes on in the innumerable commercial coaching services promising to raise SAT scores. Few people think of the prep courses in that way. On the surface, it is all about getting into the college of your choice. But raising an SAT is just like raising an IQ if the SAT is an intelligence test and, however adroitly the current officials of the College Board and the admissions officers in universities try to avoid saying so, the SAT is partly an intelligence test.43

Can the SAT be coached? Yes, but it is not easy. Everyone who looks into this topic immediately hears about students who gained 100, 150, or 200 points on the SAT after a few hours of coaching. The tales may even be true, but they need to be averaged with the tales that don’t get told about the scores that improve by only a few points—and the scores that drop—after spending a few dozen hours and hundreds of dollars on a coaching course. Scholars have by now largely sorted out the reality behind the sales pitches. After a furious debate about the issue in the late 1970s and early 1980s, the best evidence indicates that the coaching programs which can offer convincing scientific backing for their claims consist not of a few hours of practice but of lengthy training, comparable to going to school full time.44 In the best of these analyses, Samuel Messick and Ann Jungeblut reviewed the published studies on coaching for the SAT, eliminated the ones that were methodologically unsound, and estimated in a regression analysis the point gain for a given number of hours spent studying for the test.45 Their estimate of the effect of spending thirty hours on either the verbal or math test in a coaching course (including homework) was an average of sixteen points on the verbal SAT and twenty-five points for the math SAT Larger investments in time earn larger payoffs with diminishing returns. For example, 100 hours of studying for either test earns an average twenty-four points on the verbal SAT and thirty-nine points on the math SAT The next figure summarizes the results of their analysis.

Studying really does help, but consider what is involved. Sixty hours of work is not a trivial investment of time, but it buys (on average) only forty-one points on the combined Verbal and Math SATs—typically not enough to make much difference if a student is trying to impress an admissions committee. Even 300 hours—and now we are talking about two additional hours for 150 school days—can be expected to reap only seventy additional points on the combined score. And at 300 hours (150 for each test), the student is already at the flat part of the curve. Double the investment to 600 hours, and the expected gain is only fifteen more points.

The diminishing returns to coaching for the SAT


Source: Messick and Jungeblut 1981, Figs. 1, 3.

Although intended for utterly different purposes, the benefits of the Venezuelan program and of SAT coaching schools are remarkably similar. The sixty lessons of the Venezuelan course, representing forty-five hours of study, added between .1 and .4 standard deviation on various intelligence tests. From the figure on SAT coaching, we estimate that 45 hours of studying adds about .16 standard deviation to the Verbal score and about .23 standard deviation to the Math score.46

These increases in test scores represent a mix of coaching effects—“cramming” is the process, with a quite temporary effect, that you may remember from school days—and perhaps an authentic increase in intelligence. We also are looking at short-term results here and must keep in mind that whenever test score follow-ups have been available (see the next section), the gains fade out. The net result is that any plausible estimate of the long-term increase in real cognitive ability must be small, and it is possible to make the case that it approaches zero.

Taken together, the negative findings about the effects of natural variation in schools, the findings of no effect except maybe to slow the falling-behind process in the evaluations of compensatory education, and the results of the Venezuelan and SAT coaching efforts all point to the same conclusion: As of now, the goal of raising intelligence among school-age children more than modestly, and doing so consistently and affordably, remains out of reach.


During the 1970s when scholars were getting used to the disappointing results of programs for school-age children, they were also coming to a consensus that IQ becomes hard to budge at about the time children go to school. Longitudinal studies found that individual differences in IQ stabilized at approximately age 6.47 Meanwhile, developmental psychologists found that the year-to-year correlations in mental test performance were close to zero in the first few years of life and then rose to asymptotic levels by age 6.48 These findings conformed with the intuitive notion that, in the poet’s words, “as the twig is bent the tree’s inclined.” 49 Any intervention designed to increase intelligence (or change any other basic characteristics of the child) must start early, and the earlier the better.50 Here, we will characterize the more notable attempts to help children through preschool interventions and summarize the expert consensus about them.

Preschool Programs for Disadvantaged Children in General

HEAD START. One of the oldest, largest, and most enduring of the contemporary programs designed to foster intellectual development came about as the result of the Economic Opportunity Act of 1964, the opening salvo of Lyndon Johnson’s War on Poverty. A year later, the mandated executive agency, the Office of Economic Opportunity, launched Project Head Start, a program intended to break the cycle of poverty by targeting preschool children in poor families.51 Designed initially as a summer program, it was quickly converted into a year-long program providing classes for raising preschoolers’ intelligence and communication skills, giving their families medical, dental, and psychological services, encouraging parental involvement and training, and enriching the children’s diets.52 Very soon, thousands of Head Start centers employing tens of thousands of workers were annually spending hundreds of millions of dollars at first, then billions, on hundreds of thousands of children and their families.

The earliest returns on Head Start were exhilarating. A few months spent by preschoolers in the first summer program seemed to be producing incredible IQ gains—as much as ten points.53 The head of the Office of Economic Opportunity54 reported the gains to Congress in the spring of 1966, and the program was expanded. By then, however, experts were noticing the dreaded “fade-out,” the gradual convergence in test scores of the children who participated in the program with comparable children who had not. To shorten a long story, every serious attempt to assess the impact of Head Start on intelligence has found fade-out.55 Cognitive benefits that can often be picked up in the first grade of school are usually gone by the third grade. By sixth grade, they have vanished entirely in aggregate statistics.

Head Start programs, administered locally, vary greatly in quality. Perhaps, some have suggested, the good programs are raising intelligence, but their impact is diluted to invisibility in national statistics.56 That remains possible, but it becomes ever less probable as time passes without any clear evidence for it emerging. To this point, no lasting improvements in intelligence have ever been statistically validated with any Head Start program. Many of the commentators who praise Head Start value its family counseling and public health benefits, while granting that it does not raise the intelligence of the children.57

One response to the disappointment of Head Start has been to redefine its goals. Instead of raising intelligence, contemporary advocates say it reduces long-term school failure, crime, and illegitimacy and improves employability.58 These delayed benefits are called sleeper effects, and they are what presumably justify the frequent public assertions that “a dollar spent on Head Start earns three dollars in the future,” or words to that effect.59 But even these claims do not survive scrutiny. The evidence for sleeper effects, such as it is, almost never comes from Head Start programs themselves but from more intensive and expensive preschool interventions.60

PERRY PRESCHOOL. The study invoked most often as evidence that Head Start works is known as the Perry Preschool Program. David Weikart and his associates have drawn enormous media attention for their study of 123 black children (divided into experimental and control groups) from the inner city in Ypsilanti, Michigan, whose IQs measured between 70 and 85 when they were recruited in the early 1960s at the age of 3 or 4.61 Fifty-eight children in the program received cognitive instruction five half-days62 a week in a highly enriched preschool setting for one or two years, and their homes were visited by teachers weekly for further instruction of parents and children. The teacher-to-child ratio was high (about one to five), and most of the teachers had a master’s degree in appropriate child development and social work fields. Perry Preschool resembled the average Head Start program as a Ferrari resembles the family sedan.

The fifty-eight children in the experimental group were compared with another sixty-five who served as the control group. By the end of their one or two years in the program, the children who went to preschool were scoring eleven points higher in IQ than the control group. But by the end of the second grade, they were just marginally ahead of the control group. By the end of the fourth grade, no significant difference in IQ remained.63 Fadeout again.

Although this intensive attempt to raise intelligence failed to produce lasting IQ gains, the Ypsilanti group believes it has found evidence for a higher likelihood of high school graduation and some post-high school education, higher employment rates and literacy scores, lower arrest rates and fewer years spent in special education classes as a result of the year or two in preschool. The effects are small and some of them fall short of statistical significance.64 They hardly justify investing billions of dollars in run-of-the-mill Head Start programs.

OTHER LONGITUDINAL STUDIES OF PRESCHOOL PROGRAMS. One problem faced by anyone who tries to summarize this literature is just like that faced by people trying to formulate public policy. With hundreds of studies making thousands of claims, what can be concluded? We are fortunate to have the benefit of the efforts of a group of social scientists known as the Consortium for Longitudinal Studies. Initially conceived by a Cornell professor, Irving Lazar, the consortium has pulled together the results of eleven studies of preschool education (including the Perry Preschool Project), chosen because they represent the best available scientifically.65 None of them was a Head Start program, but a few were elaborations of Head Start, upgraded and structured to lend themselves to evaluation, as Head Start programs rarely do. The next figure summarizes the cognitive outcomes in the preschool studies that the consortium deemed suitable for follow-up IQ analysis. The reported changes control for pretest IQ score, mother’s education, sex, number of siblings, and father presence.

Soon after completing one of these high-quality experimental preschool programs, the average child registers a net gain in IQ of more than seven IQ points, almost half a standard deviation. The gain shrinks to four to five points in the first two years after the program, and to about three points in the third year.66 The consortium also collected later follow-up data that led the researchers to conclude that “the effect of early education on intelligence test scores was not permanent.”67

Intensive Interventions for Children at Risk of Mental Retardation

The preschool programs we have just described were targeted at disadvantaged children in general. Now we turn to two studies that are more intensive than even the ones analyzed by the consortium and deal with children who are considered to be at high risk of mental retardation, based on their mothers’ low IQs and socioeconomic deprivation.

IQ gains attributable to the Consortium preschool projects


Source: Lazar and Darlington 1982, Table 15.

A case can be made for expecting interventions to be especially effective for these children, since their environments are so poor that they are unlikely to have had any of the benefits that a good program would provide. Moreover, if the studies have control groups and are reasonably well documented, there is at least a hope of deciding whether the programs succeeded in forestalling the emergence of retardation. We will briefly characterize the two studies approximating these conditions that have received the most scientific and media attention.

THE ABECEDARIAN PROJECT. The Carolina Abecedarian Project started in the early 1970s, under the guidance of Craig Ramey and his associates, then at the University of North Carolina.68 Through various social agencies, they located pregnant women whose children would be at high risk for retardation. As the babies were born, the ones with obvious neurologic disorders were excluded from the study, but the remainder were assigned to two groups, presumably randomly. In all, there were four cohorts of experimental and control children. Both groups of babies and their families received a variety of medical and social work services, but one group of babies (the “experimentals”) went into a day care program. The program started when the babies were just over a month old, and it provided care for six to eight hours a day, five days a week, fifty weeks a year, emphasizing cognitive enrichment activities with teacher-to-child ratios of one to three for infants and one to four to one to six in later years, until the children reached the age of 5. It also included enriched nutrition and medical attention until the infants were 18 months old.69 The Abecedarian Project is the apotheosis of the day care approach. This is extremely useful from a methodological perspective: Even if the nation cannot afford to supply the same services to the entire national population of children who qualified for the Abecedarian Project, it serves as a way of defining the outer limit of what day care can accomplish given the current state of the art.

At the end of the fifth year, the children receiving the day care outscored those who did not by half a standard deviation on an intelligence test. At last report, the children were 12 years old and were still doing better intellectually than the controls. Combining all the cohorts, only 28 percent of the experimental children had repeated a grade, compared to 55 percent of the control children. Only 13 percent of the experimental children had IQs of less than 85, compared to 44 percent of the control children.70

This would be unequivocal good news, except for charges that the two groups were not comparable in their intellectual prospects at birth. Ignoring the more technical issues, the major stumbling block to deciding what the Abecedarian Project has accomplished is that the experimental children had already outscored the controls on cognitive performance tests by at least as large a margin (in standard score units) by the age of 1 or 2 years, and perhaps even by 6 months, as they had after nearly five years of intensive day care.71 There are two main explanations for this anomaly. Perhaps the intervention had achieved all its effects in the first months or the first year of the project (which, if true, would have important policy implications). Or perhaps the experimental and control groups were different to begin with (the sample sizes for any of the experimental or control groups was no larger than fifteen and as small as nine, so random selection with such small numbers gives no guarantee that the experimental and control groups will be equivalent). To make things still more uncertain, test scores for children younger than 3 years are poor predictors of later intelligence test scores, and test results for infants at the age of 3 or 6 months are extremely unreliable. It would therefore be difficult in any case to assess the random placement from early test scores. The debate over the results is ongoing and unresolved as we write.

THE MILWAUKEE PROJECT. The Abecedarian Project was inspired by an earlier attempt to forestall mental retardation in a population of children who were at high risk. The famous Milwaukee Project started in 1966 under the supervision of Richard Heber, a professor at the University of Wisconsin (Madison) who had been research director of President John F. Kennedy’s panel on mental retardation at the beginning of the decade. Healthy babies of poor black mothers with IQs below 75 were almost, but not quite, randomly assigned to no day care at all or day care starting at 3 months and continuing until they went to school. The day care lasted all day, five days a week, all year. The families of the babies selected for day care received a variety of additional services and health care. The mothers were paid for participation, received training in parenting and job skills, and their other young children received free child care. Only thirty-five children are considered to have completed the study, seventeen receiving the special attention and the remainder serving as controls.

Soon after the Milwaukee project began, reports of enormous net gains in IQ (more than 25 points) started appearing in the popular media and in psychology textbooks.72 However, there was a dearth of publication that allowed experts to evaluate the project. The few technical items that appeared raised more questions than they answered.73 It was not until 1988 that another Wisconsin professor associated with the work, Howard Garber, published an interpretable analysis of what had been done in the Milwaukee Project and what was found.74

By the age of 12 to 14 years, the children who had been in the program were scoring about ten points higher in IQ than the controls. Compared to other early interventions, this is a notably large difference. But this increase was not accompanied by increases in school performance compared to the control group. Experimental and control groups were both one to two years retarded in reading and math skills by the time they reached fourth grade; their academic averages and their achievement scores were similar, and they were similarly rated by their teachers for academic competence. From such findings, psychologists Charles Locurto and Arthur Jensen have concluded that the program’s substantial and enduring gain in IQ has been produced by coaching the children so well on taking intelligence tests that their scores no longer measure intelligence or g very well.75 Time will tell whether a more hopeful conclusion can be drawn.

In summary, the two experiments contain some promising leads. But it is not obvious where to go from here, for they differed in possibly important ways. The Abecedarian Project evaluated day care; the Milwaukee Project provided numerous interventions besides day care, including parental payment and training. It is hard to tell whether the former found enduring IQ benefits, given the very early divergence in test scores for experimental and control groups, but it found some academic benefits; the latter found an enduring IQ gain, but has not yet shown comparable intellectual gains in school work. It may be relevant that the Abecedarian mothers had higher IQs than the Milwaukee mothers, so the children may not have been at equal risk for retardation.

Reading this history of interventions, you may have noticed a curious parallelism: In the media, the good news is trumpeted as if there were no ambiguity; in the technical journals, the good news is viewed with deep suspicion and discounted. Are the scholars as excessively nitpicking as the journalists are credulous? Here is the difficult-to-discuss problem that overhangs the interpretation of these results: The people who run these programs want them to succeed. This is hardly a criticism. People who are spending their lives trying to help disadvantaged children ought to be passionately committed to their success. But it is hard for them to turn around and be dispassionate about the question, “How well are we doing?” Often the raw data from these programs are not easily accessible to outside scholars. Not infrequently, when such data finally are made available, they reveal a different and less positive way of viewing the successful results than the one that had previously been published.

Consensus has thus been hard to reach, but progress is being made. In our account, we have avoided dwelling on technical problems that, though perhaps valid, would modify the results only at the margin. When we have alluded to uncertainties and methodological difficulties, we have restricted ourselves to clear potential problems, which, if true, seriously weaken the basis for claiming success. In other words, we have tried to avoid nitpicking. The fact is that we and everyone else are far from knowing whether, let alone how, any of these projects have increased intelligence. We write this pessimistic conclusion knowing how many ostensibly successful projects will be cited as plain and indisputable evidence that we are willfully refusing to see the light.


There is one sure way to transform a child’s environment beneficially: adoption out of a bad environment into a good one. If adoption occurs at birth, it is at least possible that the potential effects of postnatal environmental disadvantage could be wiped out altogether.76 The specific question now is: How many points does being raised in a good adoptive home add to an IQ score?

Children are not put up for adoption for the edification of social theorists. There are no controlled experiments on the effects of adoption. Adoption usually means trouble in the biological family; trouble usually lands on families nonrandomly and unaccountably, making it hard to extract clear, generalizable data. The most famous studies were mostly done decades ago, when the social and financial incentives for adoption were different from today’s. Legalized contraception and abortion, too, have altered the pool of subjects for adoption studies. Both the environmental and genetic legacies of children put up for adoption have surely changed over the years, but it is impossible to know exactly in what ways and how much. In short, although data are abundant and we will draw some broad conclusions, this is an area in which solid estimates are unlikely to be found.

When Environment Is Decisive

Lest anyone doubt that environment matters in the development of intelligence, consider the rare and bizarre cases in which a child is hidden away in a locked room by a demented adult or breaks free of human contact altogether and runs wild. From the even rarer cases that are investigated and told with care and accuracy, we know that if the isolation from human society lasts for years, rather than for just months, the children are intellectually stunted for life.77 Such was, for example, the experience of the “Wild Boy of Aveyron,” discovered in southern France soon after the Revolution and the establishment of the first French Republic, like an invitation to confirm Rousseau’s vision of the noble savage. The 12- or 13-year-old boy had been found running naked in the woods, mute, wild, and evidently out of contact with humanity for most of his life. But, as it turned out, neither he, nor the others like him that we know about, resemble Rousseau’s noble savage in the least. Most of them never learn to speak properly or to become independent adults. They rarely learn to meet even the lowest standards of personal hygiene or conduct. They seem unable to become fully human despite heroic efforts to restore them to society. From these rare cases we can draw a hopeful conclusion: If the ordinary human environment is so essential for bestowing human intelligence, we should be able to create extraordinary environments to raise it further.78

As a group, adopted children do not score as high as the biological children of their adopting parents.79 The deficit may be as large as seven to ten IQ points. It’s not completely clear what this deficit means. One hypothesis is that the adopted children’s genes hold them back; another is that there is an intellectually depressing effect of adoption itself, or that being placed in adopting homes not immediately after birth (as only some of them are), but only after several months or years, loses the benefit of the nurturing their adopting parents would have provided earlier in their lives.

At the same time, researchers think it very likely that adopted children earn higher scores than they would have had if they been raised by their biological parents, because the adopting home environment is likely to be better than the one their biological parents would have provided. If so, this would be a genuine effect of the home environment. How large is the effect? Charles Locurto, reviewing the evidence and striking an average, concludes that it is about six points.80 As a consensus figure, that seems about right to us. However, a consensus figure is not what we want, as Locurto recognizes. It does not identify how wide a gap separates the environments provided by adopting homes and the homes in which the children would have been reared had they not been adopted. We seek a comparison of the IQs of children growing up in homes of a known low socioeconomic status and genetically comparable children reared in homes of a known high socioeconomic status. What would the increment in IQ look like then?

Two approximations to an ideal adoption study, albeit with very small samples, have recently been done in France.81 In one, Michel Schiff and his colleagues searched French records for children abandoned in infancy, born to working-class (unskilled) parents, who were adopted into upper-class homes. Only thirty-two children met the study’s criteria. In childhood, their average IQ was 107. To understand what this means, two further comparisons are in order. First, the adopted children scored eight points lower on average than their schoolmates, presumably from comparable upper-class homes. This confirms the usual finding with adopted children. But, second, they scored twelve points higher than twenty of their full or half-siblings who were reared at least for a time by a biological parent or grandparent in lower-class surroundings.82 This study provides a rare chance to estimate roughly where the adoptees would have been had they remained in their original homes.

A second French study compared four small groups of adopted children, reared in either high- or low-SES homes, and the biological offspring of high- or low-SES parents. Thus one could ask, albeit with only a handful of children,83 what happens when children born to low-SES parents are adopted into a high-SES home or when children born to high-SES parents are adopted into low-SES homes; and so on. In this study as well, the switch from low to high status in the home environment produced a twelve-point benefit in IQ.84 Such findings, of course, implicate the home environment as a factor in the development of cognitive ability. We cannot be sure how much, because we do not know exactly how far down the SES ladder the children came from, or how far up the ladder they were moved into their adoptive homes. If the twelve-point shift is produced by a small shift in environment (e.g., a child of a truck driver adopted by the family of a bank clerk), it gives a great deal of hope for the effects of adoption; if it was produced only by a huge shift in the environment (e.g., the child of a chronically unemployed illiterate adopted by the Rothschilds), not so much hope. In general, the more important the environment is in shaping cognitive ability, the larger the impact a given change in environment has on IQ.

To see what the policy implications might be, let us suppose that low-and high-SES homes in the French studies represented the 10th and 90th centiles in the quality of the home environment, respectively. If that were the case, what might be accomplished by moving children from very deprived homes (at the 2d centile, to make the example concrete) to very advantaged ones (98th centile)? The results of the French study imply that such a shift in home environment would produce a benefit of almost twenty IQ points.85

A swing of twenty points is considerable and seems to open up the possibility of large gains in intelligence to be had by equalizing homes “upward,” by appropriating for more families whatever nurturing things go on in the homes of the top 1 or 2 percent in socioeconomic status.86 The problem, obviously, is that no one knows how to equalize environments upward on so grand a scale, particularly since so much of what goes on in the nurturing of children is associated with the personality and behavior of the parent, not material wealth. This brings us to a variety of policy issues that it is now time to discuss more explicitly.



Nothing is more predictable than that researchers will conclude that what is most needed is more research. In this case, however, the usually predictable is a little less so.

Certain kinds of research are not needed. Next to nothing is to be learned about how to raise IQ by more evaluations of Head Start, or even by replicating much better programs such as Perry Preschool or Abecedarian. The main lesson to be learned from these better programs has already been learned: It is tough to alter the environment for the development of general intellectual ability by anything short of adoption at birth. By now, researchers know enough to be confident that, the next demonstration program is not going to be the magic bullet, because they have already demonstrated beyond dispute that the “environment” is an unimaginably complex melange of influences and inputs for all the child’s waking hours (and perhaps some sleeping hours too). No meaningful proportion of that melange can reasonably be expected to be shaped by any outside intervention into the child’s social environment, even one that lasts eight hours a day, using the repertoire of techniques now available. To have a large effect, we need new knowledge about cognitive development.

New knowledge is likely to come from sharply focused investigations into the development of cognitive ability, conducted in an atmosphere that imposes no constraints on the researchers other than to seek and find useful knowledge within commonly accepted ethical constraints. The most promising leads may come from insights into the physiological basis of intelligence rather than from the cultural or educational variables that have been customary in educational research. Long-term funding, buffers against bureaucratic meddling, readiness to fund research on the hardest questions, if they are brought forward by the inner logic of the science, and not just the politically correct questions: This is what is needed, and what today’s research programs seldom provide. With that set of caveats on the table, more research is indeed at the top of our policy agenda. Because intelligence is less than completelyheritable, we can assume that, some day, it will be possible to raise the intelligence of children through environmental interventions. But new knowledge is required. Scientific research is the only way to get it.


Advocating that all children receive good nutrition does not come under the heading of daring new ideas. We advocate it nonetheless. Especially if the inconsistent but suggestive results about the effects of vitamin and mineral supplements on cognitive functioning are borne out, it would be worth considering such supplements as part of school and preschool lunch programs.

Investment in Schooling

When quantum changes are made in education—moving from no education to an elementary education, or from 6 years of schooling to 12—then broad gains can occur, but the United States has in most respects passed this stage. Additional attempts to raise IQ through special accelerated courses have modest effects: short-term gains of two to four IQ points after extensive training. Long-term gains are less clear and likely to be smaller. In short, the school is not a promising place to try to raise intelligence or to reduce intellectual differences, given the constraints on school budgets and the state of educational science.

General Purpose Preschool Programs

Much is already known about what can be accomplished by ordinarily good preschool interventions—“ordinarily good” meaning that a few modestly trained adults who enjoy being with children watch over a few dozen children in a pleasant atmosphere. It is hard to know how many Head Start programs reach this standard. But a vast amount of research tells us that even ordinarily good Head Starts do not affect cognitive functioning much if at all. There is no reason to think that any realistically improved version of Head Start, with its thousands of centers and millions of participants, can add much to cognitive functioning. Even the claims for long-term benefits of Head Start on social behavior are unsubstantiated.

Such findings do not invalidate Head Start’s value as a few hours’ daily refuge for small children who need it. But the debate over Head Start should move away from frivolous claims about how many dollars it will save in the long run, none of which stands up to examination, and focus instead on the degree to which it is actually serving the laudable and more fundamental function of rescuing small children from unsuitable, joyless, and dangerous environments.

Highly Targeted Preschool Programs

The nation cannot conceivably implement a Milwaukee Project or Abecedarian Project for all disadvantaged children. It is not just the dollar costs that put such ambitions out of reach (though they do) but the impossibility of staffing them. With teacher-to-child ratios ranging as high as one to three and staff-to-child ratios even higher, these programs come close to calling for a trained person per eligible child.

But should such programs be mounted for the extremes—the children far out in the left-hand tail of home environments? We are not talking about children who are just poor or just living in bad neighborhoods, but children who are at high risk of mental retardation in an awful environment, with parents who function at a very low cognitive level. Should such children be enrolled, within a few weeks of birth, in a full-time day care setting until they begin kindergarten?

The decision cannot be justified purely on grounds of cognitive benefits, judging from what has come out of the Milwaukee and Abecedarian projects. On the other hand, the evidence about improvements in social adjustment from the Perry Preschool Project may be relevant, if they stand up to further critical scrutiny. If they do, then highly intensive preschool programs have an important role to play in socializing children from highly disadvantaged backgrounds. Such results are not as hopeful as they are sometimes portrayed, but they may be substantial. Earlier, we said that the cost-benefit claims for Head Start could not withstand examination. For programs that achieve results comparable to those claimed for Perry Preschool, perhaps they could. But even this limited endorsement is applicable only to the small fraction of the population that is both at substantial risk for mental retardation and living in the worst conditions. Comparatively few children typically classified as “disadvantaged” fall in that category.


Adoption at birth from bad environments into good environments raises cognitive functioning, especially in childhood and by amounts that are not well established. In general, the worse the home that would have been provided by the biological parents and the better the adoptive home, the greater is the cognitive benefit of adoption. Adoption at birth seems to produce positive noncognitive effects as well. In terms of government budgets, adoption is cheap; the new parents bear all the costs of twenty-four-hour-a-day care for eighteen years or so. The supply of eager and qualified adoptive parents for infants is large, even for infants with special needs.

If adoption is one of the only affordable and successful ways known to improve the life chances of disadvantaged children appreciably, why has it been so ignored in congressional debate and presidential proposals? Why do current adoption practices make it so difficult for would-be parents and needy infants to match up? Why are cross-racial adoptions so often restricted or even banned? All these questions have political and social answers that would take us far outside our territory. But let it be said plainly: Anyone seeking an inexpensive way to do some good for an expandable number of the most disadvantaged infants should look at adoption.

The tough question about adoption involves the way the adoption decision is made. Governments should not be able to force parents to give up their children for any except the most compelling of reasons. Right now, the government already has the power (varying by state), based on evidence of neglect and abuse, which we do not advocate expanding. Instead, we want to return to the state of affairs that prevailed until the 1960s, when children born to single women—where much of the problem of child neglect and abuse originates—were more likely to be given up for adoption at birth. This was, in our view, a better state of affairs than we have now. Some recommendations for turning back this particular clock are in Chapter 22.


An inexpensive, reliable method of raising IQ is not available. The wish that it were is understandable, and to pursue the development of such methods is worthwhile. But to think that the available repertoire of social interventions can do the job if only the nation spends more money on them is illusory. No one yet knows how to raise low IQs substantially on a national level. We need to look elsewhere for solutions to the problems that the earlier chapters have described.