Galton, Sir Francis (1822–1911)

A prodigy, Sir Francis Galton was born of two important families. His mother was Charles Darwin's aunt and the daughter of Erasmus Darwin. His father's line included wealthy bankers and gunsmiths. By age six, Galton was conversant with the Iliad and the Odyssey. At age seven, he read Marmion's, Cowper's, Pope's, and Shakespeare's works for pleasure. After reading a page twice, he could repeat the text verbatim.

After studying medicine and mathematics at Cambridge and failing to excel in either discipline, Galton took a poll degree in 1843. After his father died, Galton pursued his passion for exploration. In so doing, he became a published author, received gold medals from two geographic societies, and was elected to the Royal Society. Galton developed a method for mapping atmospheric circulation and was the first to recognize the effects of high-pressure systems on weather. Another of his achievements was research proving that one's fingerprints are unique.

In statistics, Galton showed that the law of error could be used not only to estimate true scores, but also to investigate populations in terms of individuals' deviations from the mean. He developed the concept of regression, which allowed for the first scientific attempts to study the relationship of heredity and human behavior. Galton measured the heights of children and their parents. He plotted the data in such a fashion that the initial regression line decreased the error in prediction. Using sweet pea samples selected on the basis of the weight of parent seeds, he discovered that the progeny seed weights reverted (i.e., regressed) toward the mean of the parent distribution. This discovery led to the development of the concept of correlation. The statistical concepts of regression toward the mean and correlation allowed the field of psychometrics to move forward significantly. Researchers were able to study the stability of human attributes. For instance, through the use of regression and correlation, the relationship between the intelligence scores of parents and their children could be examined.

In Hereditary Genius (1869), Galton contended that intellect is inherited. To collect evidence to test his theory, he founded an anthropometric laboratory through which he measured an array of physical attributes (e.g., height, reaction time, and head circumference). Although his notion was fatally flawed, throughout his life Galton argued that nature dominates nurture in the development of human mental ability.

Galton used Darwin's comments on the selective breeding of plants and animals to suggest that humans could be improved by similar methods. In 1883, he coined the term for such practices, eugenics, and a long and bitter controversy ensued. Although his name is often linked to negative eugenics (e.g., Hitler's attempts to exterminate “inferior races”), for the most part Galton favored positive approaches (e.g., “genetically superior” people should marry early and produce more children). Nevertheless, he urged that “undesirables” be restricted from free reproduction, even supporting their sterilization.