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Quality of Population


Population quality is the overall level of certain desirable traits in a specific population. The members of a population do not contribute equally to the size of the next generation: The distribution of births, especially in low-fertility populations, varies markedly across the adult members. Because the data seem to show family resemblances across generations in these traits (the traits are familial whether they are transmitted genetically or socially), the question arises whether their overall level is going up or down as a result of this unequal distribution of births.

Increasing the Incidence of Desirable Traits

In most discussions of population quality the traits in question are health, intelligence, and what the scientist Sir Francis Galton, the coiner of the term eugenics, called "moral character"; this is frequently interpreted by modern psychologists as the personality traits of conscientiousness and altruism. However difficult it may be to define and assess such qualities in ways that command wide agreement, let alone consensus, it is obvious that people want to live in a society whose members are healthy, intelligent, conscientious, considerate, and civil toward others and prefer not to live in a society whose members are on the whole unhealthy, unintelligent, dishonest, lazy, and uncivil. The question, then, is how social policies in a specific population could be devised to increase the frequency of members with high amounts of the good traits and decrease the frequency of those with low amounts and whether such policies should even be sought.

A commonly discussed method of increasing the frequency of those with the good traits and decreasing the frequency of those without them is eugenics. Eugenic methods are applicable when the trait in question is inherited in some fashion, and many of those traits seem to be. What Richard Lynn (2001) calls "classical eugenics" seeks to increase the reproductive rates of those with higher levels of the desired traits and decrease the reproductive rates of those without them. This would counteract the tendency, perceived by many observers, of people who are better endowed with intelligence or the personality traits of conscientiousness and civility to replace themselves in the next generation at lower rates than those of people with low intelligence or minimal conscientiousness or civility.

Problems with Eugenics

There are problems with a program of eugenics. Assuming that agreement about desirable and undesirable traits can be reached, probably the most important problem is time. Generation length (the average time between two successive generations) among human beings is between 25 and 30 years, and for males it is often even longer. Because eugenics programs propose changing the frequency of a trait in the next generation, such programs would take 20 or more years to have an effect. This may be too long in comparison to other changes affecting human populations.

The eugenicist Hermann Muller (1890–1967), a Nobel Prize winner in medicine, wrote about this problem, noting the "creeping pace" of dysgenic trends compared to the "fast growing menaces presented by our cultural imbalances" (Muller 1973, p.128). Konrad Lorenz (1903–1989), also a Nobel Prize winner, worried about the genetic quality of the human species. Late in his life, however, he allowed that cultural deterioration proceeds much more rapidly than does genetic deterioration (Lorenz 1976). This argument against the efficacy of eugenics has not been answered.

Of course, if change in the quality of a population is due in large part to the environment in which the members of that population live, change can take place considerably faster than the slow pace of genetic change. However, Richard Lynn has shown in his books Dysgenics (1996) and Eugenics (2001) that important traits such as intelligence, conscientiousness, altruism, and a psychopathic personality have significant inherited components. That conclusion strongly suggests that public policies consider eugenic measures despite the problems.

Population quality was a significant concern to an earlier generation of demographers. The goal of the Population Association of America (PAA) is defined in its constitution as the study of population in its "quantitative and qualitative aspects." Many of the founders of the PAA were eugenicists (Kiser 1981). Although the constitution of the International Union for the Scientific Study of Population (IUSSP) does not contain the phrase "population quality," the proceedings of its early conferences indicate a strong interest in the subject (Sanger 1927, Pitt-Rivers 1932). That contraception might be confined to or more prevalent among the more fit was a real concern. Arguably, the problem then identified by some demographers–the low fertility of those with large amounts of desirable traits relative to the fertility of those with low amounts–persists to this day.

The phrase, "population quality," has largely disappeared from recent demographic writings, partly because of its association with Nazi eugenic theories and programs. However, the decline of interest in population quality, and thus in eugenics, began before there was full awareness of what happened in Germany and in German-occupied lands in the Nazi era. Therefore, the reasons for the eclipse of the study of population quality in contemporary demography are not well understood.

Policies and Population Quality

A few countries have instituted demographic policies designed to cause a higher level of population quality. In China mentally retarded persons and those with genetically transmitted diseases are actively discouraged from having children. In Singapore more highly educated women are actively encouraged and given substantial financial incentives to have more children. These policies have been noted in the West but derided and not emulated. In the West persons with mental retardation, which is known to have an inherited component, are not discouraged from having children and highly educated men and women are not encouraged to reproduce.

A host of artificial methods of reproduction are existent or on the horizon, such as embryo selection and genetic engineering, that will allow parents to choose certain genetic qualities of their offspring. So far the high cost and unavailability of these methods have allowed society to avoid confronting the questions raised by what Sinsheimer (1969) calls the "new eugenics": genetic selection governed not by top-down eugenic policies but by the choices of individuals.

However, it is doubtful that consideration of these issues can be avoided much longer. There has never been a technology that has not attracted users. Any country that opted to allow and encourage the widespread employment of such technologies, as Raymond Cattell (1972, 1987) points out, would potentially render itself ascendant in light of what is already known about the heritability of various desirable traits (Lynn 1996, 2001) that are of interest to people. Less desirably, taking that option may create social problems that in the early twenty-first century are only dimly perceived.

See also: Eugenics; Family Size Distribution; Galton, Francis; Genetic Testing; Reproductive Technologies: Modern Methods, Ethical Issues.


Cattell, Raymond. 1972. A New Morality from Science: Beyondism. New York: Pergamon.

——. 1987. Beyondism: Religion from Science. New York: Praeger.

Galton, Francis. 1869. Hereditary Genius. London: Macmillan.

Kiser, Clyde. 1981. "The Role of the Milbank Memorial Fund in the Early History of the Association." Population Index 47: 490–494.

Lorenz, Konrad. 1976. "Konrad Lorenz Responds to Donald Campbell." In Konrad Lorenz: The Man and His Ideas, ed. Richard Evans. New York: Harcourt Brace Jovanovich.

Lynn, Richard. 1996. Dysgenics: The Genetic Deterioration in Modern Populations. Westport, CT: Praeger.

——. 2001. Eugenics: A Reassessment. Westport, CT: Praeger.

Muller, Hermann. 1973. "What Genetic Course Will Man Steer?" In Man's Future Birthright: Essays on Science and Humanity by H. J. Muller, ed. Elof Carlson. Albany: State University of New York Press.

Pitt-Rivers, George, ed. 1932. Problems of Population: Being the Report of the Proceedings of the Second General Assembly of the International Union for the Scientific Investigation of Population Problems. London: George Allen.

Sanger, Margaret, ed. 1927. Proceedings of the World Population Conference, Geneva. London: E. Arnold.

Sinsheimer, Robert. 1969. "The Prospect of Designed Genetic Change." Engineering and Science 32: 8–13.

Daniel R. Vining, Jr.

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