Eugenics: A Look at Eugenics in Psychology

Eugenics, a movement rooted in flawed science, once shaped psychology in dangerous ways. Preliminary psychologists promoted intelligence tests that reinforced racial and class biases, leading to forced sterilizations and harmful policies. These practices targeted marginalized groups under the guise of “improving” society. Eugenic ideas and policies affected all the world, not just a single country, highlighting the global scope and implications of the movement. While modern psychology rejects these ideas, the damage remains part of its history. Comprehension of this dark chapter helps guarantee ethical advancement in mental health research today. The past still holds lessons worth exploring.

The Origins of Eugenics in Psychology

The origins of eugenics in psychology trace back to the late 19th century, shaped by the pseudoscientific belief that human traits could—and should—be selectively controlled. Eugenics began as a popular movement during this period, spreading across countries and political spectrums with the aim of improving human populations through selective breeding. Francis Galton, inspired by Darwin’s theory of natural selection, proposed that intelligence, morality, and other traits were hereditary, making them open to manipulation.

Initial psychologists saw this as a way to “improve” society by promoting desirable characteristics while suppressing what they deemed inferior. The term eugenics was coined by Francis Galton, who introduced the word eugenics in 1883 to describe the science of improving human stock through heredity and selective breeding. Eugenicists argued that controlling reproduction could eliminate social problems, framing their ideas under the guise of scientific progress. Though some believed these efforts would lead to societal betterment, the movement ignored ethical concerns and later justified harmful practices.

The intersection of psychology and eugenics marked a troubling chapter in the field’s history, blending flawed science with moral oversights. Eugenics included a range of scientific and social ideas, from theories of heredity and evolution to controversial social reforms, and understanding its own history is crucial for learning from past mistakes.

Francis Galton and the Birth of Eugenics

Francis Galton, inspired by Charles Darwin’s work on evolution, laid the foundation for eugenics with his 1869 work Hereditary Genius, arguing that intelligence and talent were inherited traits. He believed selective breeding could improve human populations, introducing initial eugenic principles.

His ideas shaped the movement’s focus on controlled reproduction to promote desirable characteristics. Galton’s theories were based on the concept of genetic inheritance, suggesting that traits could be passed down through generations. He also drew parallels between human selective breeding and animal breeding practices, applying similar logic to both.

Galton’s Hereditary Genius

1. Statistical Foundations: Galton used data to link talent and success to lineage, claiming traits like intelligence were passed down. His work predated but influenced later interest in mendelian genetics, which provided a scientific framework for understanding inheritance.
2. Inheritance Focus: He studied families of notable figures, concluding excellence was hereditary rather than learned.
3. Selective Breeding Proposal: Galton advocated for controlled reproduction to amplify desirable traits in future generations.
4. Scientific Influence: His methods, like correlation analysis, gave eugenics a veneer of legitimacy, despite flawed assumptions.

Early genetic studies, including those inspired by Mendel, were later misapplied to justify eugenic policies.

His ideas, though influential, were later misused to justify harmful policies.

Influence of Darwinism

Darwin’s theory of natural selection didn’t just reshape biology—it also sparked ideas about human potential, inspiring Francis Galton to investigate how evolution could apply to society. Observing how traits were inherited, Galton contemplated if human evolution could be guided to heighten desirable qualities. Eugenicists believed in influencing human evolution, even if the effects were only seen to however remote a degree.

He saw Darwin’s theory as a framework for improving intelligence, health, and behavior through selective breeding. Galton argued that natural selection, left unchecked, may not assure progress, so human intervention could refine the process. His ideas laid groundwork for eugenics, suggesting society could direct human evolution by encouraging reproduction among the “fit” and discouraging it among the “unfit,” with the goal of promoting the reproduction of more suitable races. While contentious, his work reflected the era’s fascination with applying biological principles to social improvement.

Early Eugenic Principles

Though rooted in scientific curiosity, the initial principles of eugenics took shape as a controversial attempt to control human evolution. Francis Galton introduced the term in 1883, arguing that society could improve by promoting reproduction among “suitable races or strains” while limiting it for others. His ideas influenced policies targeting people based on perceived genetic fitness, often leading to discrimination.

Galton’s Vision: He believed traits like intelligence were hereditary and could be amplified through selective breeding. This approach is known as positive eugenics, which aimed to encourage the reproduction of individuals with desirable traits.

Policy Influence: Governments encouraged marriages among the “fit” and restricted the “unfit” from having children.

Institutional Support: Eugenics organizations, such as the Eugenics Education Society and the Eugenics Record Office, collected data and promoted these ideas, reinforcing societal biases.

Lasting Impact: These nascent principles laid the groundwork for harmful policies, shaping psychology and public health for decades.

The Role of IQ Testing in the American Eugenics Movement

IQ tests became a key tool for eugenicists, who claimed they could scientifically measure intelligence and justify discriminatory policies. The American eugenics movement heavily relied on IQ testing to justify its policies. These tests reinforced racial and cultural biases, falsely labeling marginalized groups as intellectually inferior.

Their misuse provided a pseudo-scientific foundation for harmful practices like forced sterilizations and restrictive immigration laws, with American eugenicists among those who promoted the use of IQ tests for discriminatory purposes.

IQ Tests and Racial Bias

Many initial IQ tests were designed with cultural biases that unfairly favored certain groups while labeling others as intellectually inferior. These iq tests became tools to reinforce eugenic ideologies, using perceived racial bias to justify discrimination.

1. Cultural Misalignment: Preliminary tests included questions rooted in white, middle-class experiences, disadvantaging non-white test-takers.
2. Flawed Interpretations: Eugenicists misused results to claim innate intelligence gaps between races, ignoring socioeconomic factors.
3. Policy Impact: Biased scores influenced immigration bans, school segregation, and forced sterilizations—policies rooted in scientific racism, which used pseudoscientific claims to justify racial hierarchies.
4. Scientific Critique: Later research exposed methodological flaws, showing intelligence isn’t fixed or purely hereditary.

Psychologists played a role in promoting these flawed assessments, lending false credibility to harmful stereotypes. While modern tests aim for fairness, their historical misuse remains a cautionary tale about science entangled with prejudice.

Scientific Justification of Eugenics

While initial IQ testing was marketed as an objective measure of intelligence, psychologists altered these tools to align with eugenic beliefs. Preliminary versions, like the Binet-Simon scale, were revised to emphasize racial and class differences in human characteristics, reinforcing stereotypes rather than providing scientific evidence.

Figures like Henry Goddard and Lewis Terman promoted IQ tests to label individuals with intellectual disability as “feebleminded,” justifying policies like forced sterilization. These tests were used to support eugenics policies, including forced sterilization and segregation. These tests often reflected cultural bias, disproportionately targeting marginalized groups.

By framing intelligence as inherited and fixed, eugenicists misused psychology to claim their ideology was rooted in science. However, later research debunked these ideas, showing that environmental factors heavily influence cognitive abilities.

Despite this flawed legacy, eugenic thinking still influenced how society viewed intelligence for decades.

Misuse of Intelligence Assessment

Several initial IQ tests became tools for discrimination rather than fair assessments of ability. Eugenicists misused intelligence tests to support biased claims about racial and ethnic groups, often ignoring cultural and socioeconomic influences. The flawed idea of a “g factor” reinforced the belief that intelligence was fixed and hereditary, justifying harmful policies.

1. Cultural Bias: Premature IQ tests favored White, middle-class norms, disadvantaging non-native speakers and marginalized communities.
2. Pseudoscientific Claims: Eugenicists like Henry Goddard used IQ tests to label people as “feeble-minded,” leading to forced sterilization and policies aimed at preventing the birth of so-called degenerate offspring.
3. Institutional Discrimination: Schools and institutions adopted IQ tests to segregate and restrict opportunities for minorities.
4. Misinterpreted Data: The “g factor” was oversimplified, ignoring environmental factors that shape cognitive development.

These practices exposed how intelligence tests were weaponized, not to measure potential, but to enforce inequality.

Psychology’s Complicity in Eugenics Movements

The history of psychology holds a troubling chapter where the field actively supported eugenics, shaping policies that harmed countless lives. The broader eugenics movement, championed by organizations such as the Race Betterment Foundation and the American Eugenics Society, promoted these ideas and influenced public policy.

Psychologists contributed to the Eugenics Education Society’s goals, promoting negative eugenics to prevent those with mental illness or low intelligence from reproducing.

Figures like Henry Goddard and Lewis Terman used flawed IQ tests to label people as “feebleminded,” justifying exclusion and control. Their theories reinforced harmful beliefs about heredity and race, leading to discriminatory practices. While these ideas have been discredited, their legacy lingers in marginalized communities.

Psychology must acknowledge this dark past to rebuild trust and guarantee ethical progress. Comprehension of this history helps prevent repeating mistakes, fostering a more inclusive future for mental health care.

Sterilization and Institutionalization Practices

Forced sterilization policies in the initial 20th century targeted individuals deemed “unfit,” often under the guise of scientific progress.

Many marginalized groups, including people with disabilities and racial minorities, were institutionalized and subjected to these practices. The Supreme Court’s 1927 ruling in Buck v. Bell upheld these measures, reinforcing their widespread use. The justification for these policies included the chilling idea that society should execute degenerate offspring, reflecting the harsh logic of eugenic ideology.

Proponents believed that by implementing these measures, desirable traits would be prevailing speedily in the population, accelerating the process of shaping human evolution according to eugenic principles.

Forced Sterilization Laws and Policies

In the initial stages of the 20th century, state-sponsored eugenics programs in the U.S. allowed the forced sterilization of tens of thousands of people—mostly those with disabilities, poor individuals, and marginalized communities. These policies targeted those labeled as “inferior people,” violating their human rights under the guise of genetic improvement.

1. Pseudoscience Justification: Claims of “defective” genes were used to justify sterilizing vulnerable groups, with organizations like the American Breeder’s Association supporting these sterilization policies.
2. Legal Backing: The 1927 Buck v. Bell Supreme Court ruling upheld forced sterilization laws.
3. Institutional Enforcement: Many victims were sterilized while confined in state-run facilities.
4. Lasting Harm: Procedures, often performed without consent, caused lifelong trauma and stripped reproductive autonomy.

Forced sterilization policies reflected deep societal prejudices, with lasting consequences for those deemed “unfit” by eugenic standards.

Institutionalization of Marginalized Groups

State-sponsored sterilization wasn’t the only tool eugenicists used to control marginalized groups—institutionalization played a key role too. In the United States, individuals with Intellectual and Developmental disabilities were often confined to overcrowded facilities, where they faced neglect and abuse.

Institutions like Cold Spring Harbor and Cold Spring Harbor Laboratory played a key role in collecting data and promoting eugenic policies, furthering the reach of these harmful practices. These institutions, driven by eugenic ideals, aimed to separate “undesirable” populations from society. Many were sterilized without consent, falsely labeled as threats to genetic purity. Immigration law also reinforced these practices, as officials turned away those deemed “unfit” at borders.

Families often had no choice but to commit loved ones, believing institutions offered care. Instead, isolation and mistreatment worsened their conditions. Over 60,000 people were sterilized under these policies, leaving lasting scars.

The dehumanizing system prioritized control over dignity, perpetuating harm for generations. Reform came slowly, but the damage endured.

Eugenics and the Classification of Intellectual Disability

While eugenics claimed to advance human improvement, it relied on harmful pseudoscience that misclassified intellectual disability as a hereditary defect. The eugenics movement began in the late 19th century and quickly spread to European countries and other countries around the world. Society often labeled developmental disabilities as undesirable traits, justifying exclusion and sterilization.

1. False Hereditary Claims: Eugenicists falsely argued that intellectual disability was inherited, leading to forced sterilizations.
2. “Feeblemindedness” Label: Broad, unscientific terms like “feeblemindedness” targeted vulnerable groups for segregation.
3. Dehumanizing Treatment: People with intellectual disabilities were stripped of autonomy under the guise of “improving” humanity.
4. Intersectional Harm: Race, disability, and sexuality intersected, amplifying discrimination against marginalized communities.

This classification system was rooted in bias, not science, and caused lasting harm. The movement’s flawed logic ignored individual potential, reducing people to genetic risks. These practices reveal how pseudoscience can mask cruelty under the pretense of progress.

Eugenics shaped laws and policies that affected millions, often under the guise of progress. Social policy in the initial 20th century drew heavily from eugenics, promoting race betterment through discriminatory measures.

The U.S. Immigration Act of 1924 restricted entry for certain ethnic groups, while forced sterilization programs targeted those deemed “unfit,” including people with disabilities. Ugly Laws barred individuals with physical differences from public spaces, and intelligence testing justified institutionalization. These policies disproportionately harmed marginalized communities, embedding pseudo-scientific bias into legal systems.

Eugenic ideals framed exclusion as societal improvement, masking prejudice as progress. These policies were justified as efforts to improve the human race. The movement’s legacy lingers in policies that once prioritized control over compassion, revealing how flawed science can fuel injustice. Comprehension of this history highlights the dangers of conflating biology with social worth.

Nazi Germany’s Use of Eugenic Psychology

1. Hereditary Health Courts – In Nazi Germany, eugenic policies were implemented based on misapplied Mendelian genetics; psychiatrists like Ernst Rüdin ordered forced sterilizations of over 400,000 people labeled “genetically inferior.”
2. Euthanasia Programs – Over 200,000 disabled individuals were murdered under the T4 program, framed as “mercy killings.”
3. Racial Pseudo-Science – Psychologists like Robert Ritter used flawed IQ tests to justify persecuting Romani people.
4. Dehumanization Tactics – Propaganda portrayed vulnerable groups as threats, shaping public opinion to accept genocide as “science.”

These abuses reveal how psychology, misused, can enable tyranny.

Modern Critiques of Eugenic Psychology

Though the past casts a long shadow, modern psychology has taken significant steps to confront and correct its ties to eugenic ideologies. A critical history reveals how initial intelligence testing was misused to justify discrimination, but today’s research rejects these flawed ideas.

Modern medical advancements, such as genetic testing and in vitro fertilization (also known as vitro fertilization), have introduced new ethical questions reminiscent of those raised by eugenics. However, these technologies are primarily used to treat disease and infertility, marking a shift from the selective breeding goals of the past to a focus on improving health outcomes and supporting individuals.

Studies show no genetic basis for linking race to intelligence, debunking eugenic claims. Psychological associations now acknowledge this dark chapter, issuing apologies and policies to prevent harm. The field has shifted focus to social and environmental influences on human beings, emphasizing inclusivity. Ethical guidelines ban practices that marginalize groups, ensuring fairness.

Ethical Reckoning in Contemporary Psychology

Modern psychology’s shift toward inclusivity and ethical standards doesn’t erase its past—it brings a responsibility to address lingering harms. The discipline must confront its historical ties to eugenics, particularly how theories rooted in “strains of blood” influenced policies targeting groups of people during and after World War II.

1. Acknowledgment: Admitting psychology’s role in justifying discrimination and forced sterilizations.
2. Reparative Research: Correcting biased studies that once claimed superiority of certain populations.
3. Policy Reform: Replacing outdated practices with equity-focused approaches.
4. Education: Teaching future psychologists about these injustices to prevent repetition.

Bottom Line

The history of eugenics in psychology casts a long shadow, much like an old wound that still aches whenever ignored. While the field has moved beyond its darker chapters, the lessons remain clear—science must serve humanity, not strip it of dignity. By embracing ethical practices and rejecting biased assumptions, modern psychology can finally step into the light, leaving pseudoscience where it belongs: in the past.