Sir Francis Galton FRS (February 16, 1822 – January 17, 1911) was an English explorer, statistician, anthropologist, creator of modern eugenics (he coined the term), investigator of the human mind, founder of psychometrics, the science of measuring mental faculties.

Historiometry and statistics

He was born into the Darwin-Wedgwood family near Sparkbrook, Birmingham and was Charles Darwin's half first cousin, his mother and Darwin's father having been children of Erasmus Darwin by separate marriages. His father was Samuel Tertius Galton, son of Samuel "John" Galton. He was advised at a young age by Charles Darwin that he ought to "read Mathematics like a house on fire," and was very much influenced by Darwin's ideas of natural selection when they came into print.

His inquiries into the mind involved detailed recording of subjects' own explanations for whether and how their minds dealt with things such as mental imagery.

Galton's 1869 work, Hereditary Genius , popularised historiometry and also formed the beginning of his thoughts on eugenics and heredity. In statistics, Galton was the first to describe and explain the common phenomenon of regression toward the mean in the 1870s and 1880s. After examining forearm and height measurements, Galton introduced the concept of correlation in 1888. His statistical study of the probability of extinction of surnames led to the concept of Galton-Watson stochastic processes.

Fingerprint

The method of identifying criminals by their fingerprints had been introduced in the 1860s by William Herschel (civil servant) in India, but their potential use in forensic work was first proposed by Dr Henry Faulds in 1880. In a Royal Institution paper in 1888 and three books (1892, 1893 and 1895) Galton wrote about the technique (inadvertently sparking a controversy between Herschel and Faulds that was to last until 1917), identifying common pattern in fingerprints and devising a classification system that survives to this day. He also estimated the probability of two persons having the same fingerprint and studied the heritability and racial differences in fingerprints.

Galton invented the Quincunx, also known as the bean machine as a tool for demonstrating the law of error and the normal distribution. He also invented the questionnaire, regression analysis, composite photography (layering images upon one another to create what he considered a 'mean' image), the correlation, and twin studies. His statistical heir, Karl Pearson, wrote a three-volume biography of Galton after his death.

He also developed early theories of ranges of sound and hearing.

Galton was knighted in 1909, and died in Haslemere, Surrey.

External link

• Galton's published work (including all his major books and over 300 of his scientific papers)

The National Portrait Gallery has 6 portraits of Galton

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