Francis Galton: Theories and History

This paper provides an overview of the work and professional life of Francis Galton and his contributions to the field of psychology. His theories and concepts are thoroughly analyzed and discussed as they impacted the evolution of psychological research and practice.

Galton’s Early Life and Work

Francis Galton was born in 1822, long before the field of psychology began to grow with the work of Sigmund Freud and William James. His early career and training were in medicine, meteorology, and mathematics and he discovered his passion for studying the inheritance of intelligence (Hunt, 1993). Based on his early observations of both highly intelligent and mentally retarded people, Galton developed a basic belief that human intelligence was hereditary. Galton held strong opinions on the need to create a highly intelligence human race, and he believed that society could advance the evolution of humans by offering the most intelligent people rewards for procreating. He believed that in a “progressive” society such as his Victorian community, innate abilities of all types must be rewarded by success. Galton believed that intelligence could be identified by a person’s physical abilities, particularly acuity of senses and fast reaction time (Hunt, 1993). His observations were highly gender-biased in that he saw men performing duties that required high levels of sensual acuity, and he believed that men were superior in intelligence to women.

Galton was deeply influenced by the work of Charles Darwin and particularly his book The Origin of Species. Darwin was Galton’s cousin, so it is possible that this lineage biased Galton’s views on intelligence. Darwin’s book turned Galton’s professional interests to heredity and evolution (Bulmer, 2003). Galton was particularly interested in how people tended to inherit specific characteristics that aided them evolutionarily. This interest in the “inheritance of intelligence” was the inspiration for Galton’s first book entitled “Hereditary Genius,” published in 1869 (Hunt, 1993). He began studying the genetic nature of evolutionary traits in animals and then began examining this process in animals.

Intelligence Testing

Galton pioneered the use of mental intelligence testing in humans, effectively inaugurating a new form of psychological research and a new field of study in the differences between individuals. Galton believed that genius was a very rare trait based on the Law of Deviation from an average as displayed by a bell curve (Hunt, 1993). He believed that his mental tests would allow him to “develop and simply identify persons of superior intelligence” (Hunt, 1993, p. 305). He created a self-questionnaire which he gave to scientific geniuses which he used to assess whether their intelligence was more due to nature (genetics) or nurture (environmental factors). The questionnaire asked questions about racial, religious, social, and political backgrounds as well as character traits and physical characteristics. Galton assessed the data to draw conclusions on whether there were more genetic or social similarities between scientific geniuses. While the subjective nature of this study, as well as its small reach, proved to be flaws in its general applicability, the study motivated Galton to continue studying intelligence. Galton found interesting correlations between visual mental imagery and scientific genius. He also devised a word association test which showed that people made associations based on personal experience (Hunt, 1993).

In addition to being the first to use intelligence testing measures, Galton created the first Twin Study. He contacted identical twins he knew and asked others to help him identify sets of twins to interview as well. He used the data to see if nurture caused them to vary from their initial similarities over the course of life. In his essay entitled “History of Twins,” Galton (1865) shared his findings in interviewing 35 sets of identical twins. He discovered significant similarities in physical and mental characteristics, but vast dissimilarities in behavioral and temperamental elements.

Another important discovery of Galton’s was correlation analysis and causal relationships (Hunt, 1993). In analyzing a scatter plot of data on children’s height, he accidentally discovered the “regression line” which showed the relationship between two variables. Later, his work was used to mathematically calculate the coefficient of correlation without the need to create scatter plots. This information allowed researchers to understand the types of relationships between two or more different sets of data.

Impact of Galton’s Theories in the Evolution of Psychology

While Galton is not well known to many psychology students and professionals (Bulmer, 2003), his work has had a large impact on the field of psychology and the study of humans. His work in human intelligence assessment, the development of twin studies have made lasting impacts by identifying correlation analysis.

Intelligence Testing

Intelligence testing has become a common practice in many fields of study. The types of tests and assessments include basic intelligence, performance aptitude, and cognitive development. These types of tests and assessments are commonly used in education, college preparedness, workplace, and psycho-social environments to test a person’s intelligence in various areas of performance (Murphy & Davidshofer, 1991). The Intelligence Quotient (IQ) test, developed by Alfred Binet, was the first commissioned test that measured mental aptitude and was inspired by the concepts presented by Galton (Hunt, 1993). The most common current intelligence test is the Wechsler Adult Intelligence Test (WAIS) which assesses an individual’s verbal comprehension, perceptual reasoning, working memory, and mental processing speed. Intelligence testing is also used in the field of psychology for predicting success in various functional areas, identifying developmental disabilities, and assessing various learning disabilities such as attention deficit disorder and dyslexia.

Twin Studies

Twin studies have become a standard assessment tool for research not only in the field of psychology but in medicine and other sciences. Twin studies are a “valuable source of information about the genetic basis and epidemiology of complex traits” (Boosma, Busjahn, & Peltonen, 2002, p. 872). By studying the correlations between genetic material and sex, age, and environmental factors, it is possible to make informed assumptions on the links between traits and a variety of physical, mental, and psychological conditions.

Galton’s first twin studies were what is now known as “Classic Twin Studies.” These compare the genetic and behavioral similarities between identical and fraternal twins in order to draw conclusions on genetic and environmental influences. Multivariate designs were later developed to study multiple genetic traits in pairs of twins in order to better assess the causes of association between different traits (Boosma et al., 2002). This development allows researchers to explore variations in and clusters of symptoms and traits, therefore gaining a better understanding of psychological disorders such as depression and anxiety.

Unlike Galton’s original sampling of a few sets of twins, there are currently local, regional, and world-wide twin registries developed to provide unbiased population samples for those wanting to conduct twin studies (Boosma et al., 2003). Researchers can call on these databases to find participants for research studies, therefore ensuring a sample that is both random and diverse.

Correlation Analysis

Correlation analysis is used in many studies that compare one variable to another in order to determine causation. Cohen, Cohen, West, & Aiken (2013) explain that correlation analysis is a very flexible data analysis system that can be used whenever a quantitative (dependent) variable is studied as a function of, or in relationship to, any other (independent) factor. The relationship can be graphed as a straight or a curved line and can be a general correlation or a conditional correlation. Additionally, since Galton’s discovery of this form of data analysis, research has shown that correlations can be causative, meaning that one variable causes the other, or spurious, meaning that the correlation is not caused and effect but instead random. Correlation analysis is used in a variety of ways including hypothesis testing, effect sizes, prediction models, and analysis of variance (Cohen et al., 2013).

Conclusion

Francis Galton developed concepts and methods which have had a great impact on the field of psychology as well as other sciences today. Although many of his viewpoints were biased and turned out to be incorrect, his innovations have changed the way research is performed. Intelligence testing plays a role in determining aptitude and potential areas. Testing is also used in the diagnosis of many Axis II disorders and influences treatment plans for these patients. Galton’s creation of the first twin study has influenced how research is conducted across all types of sciences. Twin studies are highly regarded as one of the most effective means of gathering data on genetic versus environmental factors and how they affect traits. His discovery of correlation analysis has also impacted research as this form of data analysis is used in many studies in various fields.

References

Boomsma, D., Busjahn, A., & Peltonen, L. (2002). Classical twin studies and beyond. Nature Reviews Genetics, 3(11), 872-882.

Bulmer, M. G. (2003). Francis Galton: pioneer of heredity and biometry. JHU Press.

Cohen, J., Cohen, P., West, S. G., & Aiken, L. S. (2013). Applied multiple regression/correlation analysis for the behavioral sciences. Routledge.

Hunt, M. M. (1993). The Measures. The story of psychology. New York: Doubleday.

Galton, F. (1865). Hereditary talent and character. Macmillan's Magazine, 12(157-166), 318-327.

Murphy, K. R., & Davidshofer, C. O. (1991). Psychological testing. Prentice-Hall.