by Roger Hughes


The word eugenics is used to describe the idea or practice of encouraging those people with desirable mental or physical traits to produce the most progeny. This is based on the assumption that traits like intelligence and character are, at least in part, genetically determined.

Eugenics had tended to go out of favour in the last fifty years or so. This was partly due to the misuse of eugenics by Nazi Germany. Even the idea that intelligence was an inherited trait was questioned by many academics and others.

More recently however a few individuals have begun to worry about dysgenics. Dysgenics refers to the problem of those with poor intelligence or character producing disproportionately more progeny. The result is a steady genetic deterioration in human populations.


Although the problem of dysgenics is found with a number of human characteristics, probably the most important and widely studied is intelligence. Most of this discussion will therefore deal with intelligence.

An individuals score on a test of intelligence (also referred to as cognitive ability) is a good indicator of their likelihood of success in academic or vocational pursuits. Scores on intelligence tests are often referred to as an individual's intelligence quotient or IQ. Generally the higher people progress academically the higher their IQ.

The first book on intelligence and hereditary was written by Francis Galton and came out in 1869. The book was called 'Hereditary Genius'. Since then the question of the heritability of intelligence has been one for heated debate. The debate becomes more heated when the source of differences in intelligence between different racial groups is considered.


Although Galton discussed the concept of intelligence tests he did not actually develop such a test. He did however hypothesise that when the scores of a group were graphed they would form a bell-shaped curve. Galton believed there would be wide variations in the average intelligence of different racial groups and hence each group would have a different but overlapping bell curve.

Galton was concerned about genetic deterioration for traits like intelligence and character. This was thought to be due to the tendency of eminent people to have fewer children.

Even before Galton there was concern expressed about the problem. In 1857 the French physician, Benedict Augustin Morel noted that, due to improvements in public health many infants who would have previously died were now surviving to adulthood. He argued that this would result in a deterioration in population quality, especially for traits such as physique, intellect and moral character. Morel's ideas seem to have had little influence, even amongst eugenicists.

Galton's ideas on measuring intelligence by objective tests were put into practice by the Frenchman, Alfred Binet in 1905. Binet produced the first practical test of general intelligence.

The test contained items demanding the use of language, reasoning or comprehension, and was designed to identify those children who lacked the ability to benefit from normal schooling.

Binet's test underwent a number of revisions. In 1916 a new version was produced at America's Stanford University. The test was known as the Stanford-Binet Intelligence Test and was the first to use the intelligence quotient (IQ). A person's IQ was the ratio of their mental age to their chronological age multiplied by 100. Thus a 12 year old who gained a score on the test equal to the average for twelve year olds, would have an IQ of 100. If a ten year old gained the same score he would have an IQ of 120.

The early intelligence tests tended to be administered on an individual basis. When the United States entered the First World War the government decided there was a need for group tests to classify the large influx of recruits into its armed services. Two tests that were developed were the Army Alpha and the Army Beta. It was noticed with these tests that recruits from different ethnic backgrounds varied in the average scores obtained.

After the war intelligence testing was adapted for many civilian occupations.

A characteristic of early tests was their large number of items favouring verbal skills. This in turn biased the tests to favour middle class and white collar workers over blue collar and working class people. An American, David Wechsler, designed a test containing performance or non-verbal items. This was found to reduce the class bias.


One of the most controversial questions relating to intelligence is that concerning whether it is a product of our genetic inheritance (i.e. nature) or our environment (i.e. nurture).

Following World War II and the defeat of the Nazis the general prevailing intellectual and social climate tended to favour the nurture side of the argument In other words differences in intelligence between individuals and groups were put down to environmental factors. The civil rights movement in America and a general rejection of racism and elitism further favoured the environmentalist view.

The nature side of the argument made a comeback in 1969 with an article by American Arthur Jensen. The article suggested that differences in IQ test scores between whites and blacks might be genetically based. Not long afterwards, further evidence that differences in test scores were genetically determined was described in books written by the British psychologist, Hans Eysenck.

These publications stirred up considerable controversy and criticism. Some people even suggested that research in this area should stop. The research however did not stop but was actually stimulated by the controversy. Bigger and better studies of twins, families and adoptees were carried out.


A summary of the research is as follows:

With first-degree relatives in the same environment there was an average correlation of .42 between the IQ's of parents and siblings, and a average correlation of .47 between siblings.

In adoption studies with first-degree relatives adopted apart, the correlation between parent and offspring averaged .24 and the same figure was obtained for siblings.

When comparing parents with adopted offspring the average correlation was only .19 and the correlation for genetically unrelated adoptive siblings was only .02.

Identical twins adopted apart had a correlation of .78

In twin studies the correlation for identical twins reared together was .86 and for fraternal (i.e. non-identical) reared together the correlation was .60 (Encyclopedia of Human Intelligence,1994).

The evidence would point to a strong genetic determinant for intelligence but it does not rule out some environmental influence.

Developmental Genetic Analysis

Developmental genetic analysis studies the extent to which twins' similarities change during development. Such a study also gives us an idea of how heritability can change with age.

It was found that as the subjects developed the influence of their environments waned and genetic influences became more important. Studies of genetically unrelated children adopted into the same families showed a correlation of .32 between their average IQ's. Studies of youth and young adults, also genetically unrelated and adopted into the same families showed no correlation.

It appears that environment has a greater influence on test scores during childhood than in later life.


The nature or nurture argument is most heated when racial differences are discussed.

Most of the research done in this area concerns the differences in average scores between blacks and whites in the United States. That research shows that blacks tend to score on average about 15 IQ points below the white average. Hispanics and American Indians score averages somewhere between the black and white averages. People of Korean and Japanese descent score slightly higher averages than whites.

Various rationalisations have been advanced for the differences in scores between blacks and whites. It has been suggested that as intelligence tests were first developed by middle class whites there is an in-built race and class bias. This does not explain how migrants from North-East Asia can score higher than whites. Furthermore tests in Asia have shown a difference between Chinese and Malays similar to the difference between blacks and whites in America.

A history of slavery, oppression and discrimination has also been used to justify the black-white difference. Estimates of the intelligence of blacks in Africa are actually about 10 points lower than that for American blacks. Furthermore America's black population is of mixed racial ancestry with a white European component of around 25% and an American Indian component of 8%. It is possible that history has actually played a part in raising the IQ level of black Americans.

In the south-east of the United States the black population has its lowest proportion of white genetic ancestry. The blacks there also have lower IQ on average than the blacks in the northern or western states. In other words the lower the proportion of white ancestry the lower the IQ of the black population.

The difference in IQ between blacks and whites is evident in children as young as 3 or 4, and remains fairly constant afterwards. The difference is not caused by schooling and schooling does not increase or decrease it.

Modern intelligence tests are designed to eliminate gender differences in overall scores. Nevertheless while the average scores for white males are the same as those for white females, the average scores for black males tend to be 4 to 5 points below those of black females.

It is probably significant that brain sizes differ between races. It has also been found that brain size and IQ have a correlation of .30. Taking into account overall body size it was found that blacks have brains about 100 cubic centimetres smaller than whites.

The races (or subspecies) of humanity came about by evolution and natural selection. The physical traits of each race were adaptations to their particular environments. It seems likely that as differing physical traits evolved so did different mental traits. Thus would evolve genetically determined differences in intelligence.


In 1994 controversy, similar to that which occurred when Jensen's article was published erupted again. The source of the controversy this time was a book by two American academics, Charles Murray and the late Richard Herrnstein. The book was 'The Bell Curve - Intelligence and Class Structure in American Life'.

Herrnstein and Murray describe their book as being 'about differences in intellectual capacity among people and groups and what those differences mean for America's future'. It looks not only at the question of the heritability of intelligence but also at the social impact of intelligence.

As might be expected there is a positive relationship between intelligence and academic success or earnings. There is also a relationship with social competence.

The more intellectually capable are much less likely to be affected by idleness, unemployment or injury. They were unlikely to dropout from high school, even when they came from poor families, and were more likely to benefit from a college education.

With the not so intellectually capable the picture was the reverse. Rates of unemployment idleness and injury are much higher. The likelihood of dropping out of high school are much higher and the likelihood of gaining a college education are much lower.

The contrasts do not stop there however. Poverty is much more often a problem for those of low intellect. Crime and divorce rates are higher, and competence in child raising abilities are lower. Illegitimacy rates are higher. White women in the lowest 5% of the of the intellectual distribution are six times as likely to have an illegitimate child as those in the top 5%.

More controversially, Herrnstein and Murray point out that many social inequalities between the races appear to have much to do with inequalities of intellectual capacities. The social inequalities are certainly real. In 1992, 33% of blacks in America were below the poverty line as compared to 12% of whites. In the same year the unemployment rate for whites was below 7% but the rate for blacks was 14%.

The picture looks different, however when we control for cognitive ability. For instance a bigger proportion of whites graduate from high school than do blacks or Hispanics. If we look at all young people with an IQ of say 103, we find that blacks and Hispanics are more likely to graduate than whites. Similarly whites are twice as likely to graduate from college as blacks. The average IQ of college graduates is 114. Blacks at this IQ level have a 68% chance of graduating from college. On the other hand whites at this IQ level have only a 50% chance of graduating.

The wage levels for blacks, whites and Hispanics of average age and IQ are pretty much the same.

Minorities seem to actually be over-represented in high status professions once IQ is taken into account. A white person of average age and IQ of 117 has only a 10% chance of being in a high IQ occupation. For a black of the same age and IQ the chance rises to 26%. For an Hispanic the chance is 16%.

When crime rates are considered controlling for IQ reduces the difference between racial groups but does not eliminate it. Blacks have a much higher chance of being incarcerated than whites of the same age. Considering blacks and whites of the same age and IQ, there is still a higher rate of incarceration for blacks but the difference is reduced somewhat.

Herrnstein and Murray stress that the social impact of variations in intelligence are significant, regardless of whether the differences arise from genetic or environmental factors. They do however venture into the nature versus nurture debate.

In dealing with this question they look at variations in profiles of intellectual capacity. Modern IQ tests are made up of a number of subtests which can be sorted into verbal or performance (non-verbal). While whites on average tend to score equally on verbal and performance sections, Japanese and Koreans tend to score lower on the verbal but higher on the performance. These results are similar whether the tests are done in Asia or America. It would seem that the racial variations are largely due to genes than environment.

In comparing black and white Americans, Herrnstein and Murray looked at people at one particular IQ level (say 105). A group of whites from a high socioeconomic status (SES) and IQ of 105 were compared with a group of whites of low SES but the same IQ. It was found that the profiles were basically the same on average for both groups. When whites were compared with blacks of similar IQ level there was found to be a wide variation in the profiles of each group. Again genetic differences rather than the environment would seem to be the source of the race differences.

The validity of tests has been scrutinised to see if any possible bias was evident. If a test is valid it should predict an individual's likely success in academic or vocational pursuits. Studies concentrating on the predictive validity of tests have shown no bias against blacks. In fact there is some evidence that tests are more likely to over-predict than under- predict the likely success of blacks.


Psychologists have discovered a phenomenon with cognitive ability which is difficult to explain without accepting at least some genetic determinant. It also illustrates some of the complexity of the genetic factor. The phenomenon is known as regression to the mean.

Two very dull parents or two very bright parents are unlikely to have only very dull or very bright children. The very dull parents are likely to have only a minority of their children in the very dull IQ level. The majority of the children of the very bright will not be as bright as their parents. Most of the children of both sets of parents will be either average or at an intermediate level.

Regression to the mean does not result in the whole population having average intelligence. Neither will it result in racial differences disappearing. Many average parents will have some very bright or very dull children. The constant mixing of genes will ensure a wide distribution of mental ability.


Herrnstein and Murray identified certain dysgenic tendencies in America's population. Brighter and more intelligent people married later and had fewer children. Immigration from the Third World was also thought to be dysgenic.

In 1996 a book devoted solely to the subject of dysgenics was published. The author was Richard Lynn, a noted expert in psychometrics and Director of the Ulster Institute for Social Research.

Lynn puts the problem in historical perspective. He describes how many eminent scientists in the Nineteenth and early Twentieth Centuries were concerned about dysgenics and eugenics. These included Francis Galton, Karl Pearson, Sir Julian Huxley and other important biological and social scientists. There were, for a time, societies set up to promote eugenics.

In the period after World War II and even more so in the 1960's there was a general rejection of eugenics. This was partly in reaction to the eugenic policies of Nazi Germany and partly due to the egalitarian ideas favoured by the academic community.

Nevertheless Lynn asserts that genetic deterioration has been continuing since the start of the Nineteenth Century. In more traditional societies there was natural selection of the mental and physical traits necessary for survival. With industrialisation came the control of infectious disease, improvements in public health and better nutrition. Many who would have died early in life in previous centuries were now surviving and having children. The less intelligent and educated now had higher fertility than the better educated. Social mobility allowed intelligent people from the lower classes to move up the social ladder to a class with lower fertility, hence social mobility itself was dysgenic.

The availability of various types of contraceptives added to the problem as the more intelligent and educated women were the most likely to use them efficiently. Accidental pregnancies were now more the problem of the duller and less educated women. The problem was accentuated by welfare benefits for single women who have babies.

Dysgenics occurs not only with mental ability but also with physical traits. Medical treatment has improved to the point where genetic diseases and disorders that would have once proved fatal for the afflicted, now allow them to survive. The incidence of some of these diseases is now doubling or tripling from one generation to the next. The incidence of mental retardation has increased and the retarded live longer. To make matters worse, higher levels of radiation and chemicals in the environment could be increasing the rate at which mutations occur.

Research into questions of intelligence and fertility confirm fears of a dysgenic tendency in modern populations. For instance research in Britain has shown an inverse relationship between a child's intelligence and the number of siblings. In other words the smarter the child, the fewer brothers and sisters on average.

Surprisingly perhaps, only children tend to be duller than those from families with two or three children. Family size would not appear to be an environmental factor affecting IQ. The lower scores for children from large families would seem to be mainly due to genetic factors. Further evidence for this comes from studies of adopted children which show no correlation between family size and IQ.

Estimates of the size of the decline in intelligence have varied from 2 IQ points per generation in the early part of this century to .8 of a point in recent years. The figures based on sibling studies probably under-estimate the decline as they do not take into account those who remain childless. As a general rule the childless are the more educated and intelligent in society.

Research in the United States has also revealed a negative correlation between intelligence and fertility. The dysgenic tendency is actually greater for blacks than for whites. Hence the disadvantaged position of blacks in American society is likely to worsen.

Some research has looked at the relationship between education or socioeconomic status (SES) and fertility. It was found that the well educated and those high on the SES had lower levels of fertility. Incidentally there is evidence of heritability for education.

Most of the studies related to dysgenics have been done in Britain or the United States. Nevertheless what studies have been done in Australia or Europe give similar results. Virtually all valid studies show that the more intelligent and educated have lower levels of fertility.


While there is evidence of a genetic deterioration with intelligence, actual measurements of IQ have shown a rise from generation to generation. There appears to be a contradiction as phenotype is not reflecting genotype.

This tendency for measured intelligence to increase each generation is known as the Flynn effect after James Flynn who first brought attention to it. Psychologists have allowed for it by making the tests more difficult thus keeping the median IQ score at 100. Some studies indicate that rising IQ test scores are due to improving performance by people on the lower half of the distribution of cognitive ability.

The actual cause of the Flynn effect has been the subject of speculation and controversy. It has been suggested that people are simply becoming more accustomed to the testing procedure and hence performing better.

Richard Lynn, however points out that scores have improved not only for adults but also for children, including those as young as two or three years of age. He points out that there has been a corresponding increase in average height. The reason for both rising intelligence and height is probably increased nutrition which has accompanied rising living standards. The process will not continue forever. The quality of nutrition will reach an optimum level for both height and intelligence. Once that point has been reached we can expect to see a drop in IQ test scores.


Lynn believes that there is also a dysgenic tendency for conscientiousness. This characteristic embraces such notions as social conscience, self-discipline and adherence to the work ethic. Weak conscientiousness is shown by immorality, substance abuse and indolence. At its most extreme, weak conscientiousness involves criminal activity and psychopathic personality disorder.

There is evidence based on twin studies to indicate that conscientiousness is an inherited trait. Conscientiousness is also associated with socioeconomic status. Conscientiousness, along with intelligence leads to achievement and social mobility. The lower fertility of those high on the SES results in a dysgenic tendency for conscientiousness.

Alcoholism is also, to some extent, an inherited problem and is more prevalent in the lower social orders. The higher fertility of people in the lower classes is likely to increase the problem of alcoholism.

When it comes to criminality, the problem appears considerably worse. Psychopathic males are known for their promiscuity and large numbers of children. Criminality among males has a high level of heritability. In Britain it is estimated that criminals have 77% more children than non-criminals. This in part explains the rise in crime statistics in recent years.



Immigration was cited by Herrnstein and Murray as a possible source of genetic deterioration in the American population. The problem is probably more relevant to Australia with our proportionately larger immigration intake.

It is possible that the intelligence levels of those from North East Asia are as high, or even higher than those of white Australians. However it is likely that as living standards in the region reach a similar level to those of Australia we will attract fewer migrants from there. Instead we are likely to attract migrants from the more backward areas of Asia where the populations are most likely to have lower average intelligence. Hence immigration will be dysgenic in the future.

In fact there is evidence that the migrant groups in this country with the largest family size also have the highest unemployment levels. Dysgenic problems coming from immigration may have already started.


Some years ago the Australian income tax system allowed wage and salary earners to claim a tax deduction for each dependent child. With a progressive tax system those with the highest income and marginal tax levels received the biggest deductions. The system was if anything eugenic rather than dysgenic.

Unfortunately the system was altered and most child support nowadays comes from the social service system. In 1976 the Howard Liberal government introduced their Family Tax Initiative which allows a small rebate of tax to people with dependent children. These rebates however are limited to those below certain income levels.

The present tax system is certainly not eugenic and could be dysgenic in its effects.


Australia's present social security system pays out quite a number of benefits including pensions and payments to the unemployed, single mothers and others. For those with dependent children there is the Family Payment and even a Maternity Allowance. Most of these benefits are subject to some sort of means test.

By international standards Australia's welfare system is quite liberal. Generous benefits are paid out, often to people who have never worked or paid income tax in their lives. In fact the system transfers a lot of money from the productive worker to the indolent and unemployable. No doubt there are many who deserve the benefits but in the long run it must be a serious drain on society. Perhaps worse of all it is extremely dysgenic.

The intelligent and conscientious who go out and get a job are in fact subsidising the less intelligent and less conscientious who stay home and produce nothing but children. To make the problem worse the Family Payment starts to be reduced once a worker's income reaches the princely sum of $ 23,350 per annum. Hence the working family man is penalised.


A summary of the main points covered:

1- Intelligence as measured by standardised intelligence tests has a positive correlation with academic and vocational success as well as social competence.

2- Differences in IQ scores between individuals and groups are largely, but not completely due to genetic inheritance.

3- The are dysgenic tendencies in Western societies because people of lower intelligence have higher fertility levels than those of higher intelligence.

4- Dysgenic tendencies have been masked by the Flynn effect as better nutrition has so far more than countered the genetic deterioration in intelligence. Eventually the effects of better nutrition will reach the optimum level and phenotypic deterioration will become apparent.

5- There is a dysgenic tendency in relation to conscientiousness and this is reflected to some extent in higher crime rates.

6- Australia's tax and welfare systems contribute to dysgenics.


From what has been discussed in this essay it would appear that our society can either do something about genetic deterioration or face a long-term economic and social decline. It should be possible to arrest dysgenics and possibly even replace it with eugenics.

Basically what needs to be done is to raise the incentive for the more intelligent and conscientiousness members of our society to have more children. At the same time the less intelligent, indolent or criminal members of society should lose incentives to have children, or at least large numbers of them. It should be possible to achieve this without coercion or serious harm to any individuals rights.

The re-introduction of tax deductibility for dependent children would introduce a eugenic factor into the tax system. Those with the highest incomes generally have above average levels of intelligence, and it is these people who should be encourage to have the most children.

Reducing incentives for the less gifted to have children could probably be achieved by a rationalisation of the welfare system. For instance the Family Payment should be on a sliding scale so that the average amount paid for each child reduces as the size of the family increases. Some other allowances and payments could be cut out altogether.

Rationalisation of the welfare system would probably not give the government enough in savings to pay for the proposed tax deductions for dependents. Initially the cost would be fairly high if the deductions were substantial enough to encourage a higher birth-rate. Nevertheless in the long run it could save the country massive amounts if the average brain power of the population was raised by a noticeable amount. It could for instance reduce the amount now wasted on education and welfare programs. Efficiency of all industries would improve, accidents would be less common and the general health of the population would improve.

The growth of the welfare state has not seen social problems go away. In fact some problems like chronic unemployment, illegitimacy and crime have actually increased over the last three decades. Neither has expenditure on education done anything to eliminate these problems. Even our standard of living has fallen in relative terms despite a large rise in the numbers of those completing high school or entering universities.

In the future, increasing the size of our population will not be a priority. The quality of the population however will be of utmost importance. Any policy that will increase the genetic quality of the Australian people should be pursued. Eliminating dysgenic factors and introducing eugenic factors into our welfare and taxation systems would be a good start.



BELL CURVE: When the normal distribution of intelligence scores is depicted graphically it forms a bell shaped curve with scores tending to cluster around the median.

CORRELATION: Those who have not studied statistics may not be familiar with the concept of correlation. Basically a correlation describes the relationship between two sets of scores. For instance we could compare the heights and weights of a group of people. If the tallest people were the heaviest, the shortest people the lightest, and those of intermediate height also of intermediate weight, we would have a high correlation. The best correlation possible is expressed as 1. Correlation is not causation, but if two sets of scores correlate there tends to be a relationship, either directly or indirectly.

MEAN: The average score. It is obtained by dividing the total of all scores by the number of scores.

MEDIAN: The middle score or the point where 50% of scores are below and 50% are above.


Encyclopedia of Human Intelligence, New York, MacMillan Publishing Company, 1994 Eysenck, H.J. Race, Intelligence and Education, Melbourne, Sun Books Pty Ltd, 1971 Eysenck, Hans and Eysenck, Michael. Mindwatching, London, Michael Joseph Ltd, 1981 Herrnstein, Richard J. and Murray, Charles. The Bell Curve - Intelligence and Class Structure in American Life, New York, The Free Press, 1994 Lynn, Richard. Dysgenics - Genetic Deterioration in Modern Populations, Westport, Praeger Publishers, 1996 Murphy, Kevin R. and Davidshofer, Charles O. Psychological Testing - Principles and Applications(Second Edition), Englewood Cliffs, Prentice - Hall, Inc., 1991 Social Security Payment Rates - 20 March to 30 June 1997, Canberra, Department of Social Security, 1997

For further information or feedback, write to Roger Hughes
PO Box 10, Homebush South, NSW, Australia 2140

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