Sir Francis Galton

Early life
He was born near Sparkbrook, Birmingham and was Charles Darwin's half-cousin, sharing the common grandparent Erasmus Darwin. His father was Samuel Tertius Galton, son of Samuel "John" Galton. The Galtons were famous and highly successful Quaker gun-manufacturers and bankers, while the Darwins were distinguished in medicine and science.
Both families boasted Fellows of the Royal Society and members who loved to invent in their spare time. Both Erasmus Darwin and Samuel Galton were founder members of the famous Lunar Society of Birmingham, whose members included Boulton, Watt, Wedgwood, Priestley, Edgeworth, Erasmus Darwin and other distinguished scientists and industrialists. Likewise, both families boasted literary talent, with Erasmus Darwin notorious for composing lengthy technical treatises in verse, and Aunt Mary Anne Galton known for her writing on aesthetics and religion, and her notable autobiography detailing the unique environment of her childhood populated by Lunar Society members.
Galton was by many accounts a child prodigy--he was reading by the age of 2, at age 5 he knew some Greek, Latin and long division, and by the age of six he had moved on to adult books, including Shakespeare for pleasure, and poetry, which he quoted at length. He attended numerous schools, but chafed at the narrow classical curriculum, which bored him. His parents pressed him to enter the medical profession, and he studied for two years at Birmingham General hospital and King's College Medical School in London. He followed this up with mathematical studies at Trinity College, University of Cambridge, from 1840 to early 1844. A severe nervous breakdown altered his original intention to try for honours. He elected instead to take a "poll" (pass) B.A. degree, like his cousin Charles Darwin. (Following the Cambridge custom, he was awarded an M.A. without further study, in 1847). He then briefly resumed his medical studies. The death of his father in 1844 left him financially independent but emotionally destitute, and he terminated his medical studies entirely, turning to foreign travel, sport and technical invention.
In his early years Galton was an enthusiastic traveler, and made a notable solo trip through Eastern Europe to Constantinople, before going up to Cambridge. In 1845 and 1846 he went to Egypt and traveled down the Nile to Khartoum in the Sudan, and from there to Beirut, Damascus and down the Jordan. In 1850 he joined the Royal Geographical Society, and over the next two years mounted a long and difficult expedition into then little-known South-Western Africa (now Namibia). He wrote a successful book on his experience, "Narrative of an Explorer in Tropical South Africa". He was awarded the Royal Geographical Society's gold medal in 1853 and the Silver Medal of the French Geographical Society for his pioneering cartographic survey of the region. This established his reputation as a geographer and explorer. He proceeded to write the best-selling The Art of Travel, a handbook of practical advice for the Victorian on the move, which went through many editions and still reappears in print today.
In 1853 he married Louisa Butler, who also came from an intellectually distinguished family, and after a honeymoon in Florence and Rome, they took up residence in South Kensington, where he remained almost until his death in 1911. They had no children.
Middle years
Galton was a polymath who made important contributions in many fields of science, including geography, statistics, biology and anthropology. Much of this was influenced by his penchant for counting or measuring. The result was a blizzard of discoveries and investigations as varied as detailed research into the perfect cup of tea and his discovery of the anti-cyclone. He became very active in the British Association for the Advancement of Science, presenting many papers on wide variety of topics at its meeings from 1858 to 1899. He was the general secretary from 1863 to 1867, president of the Geographical section in 1867 and 1872, and president of the Anthropological Section in 1877 and 1885.
Heredity, historiometry and eugenics
The event that changed his life and gave him direction was the publication by his cousin Charles Darwin of The Origin of Species in 1859. Galton was gripped by the work, especially the first chapter on Variation under Domestication concerning the breeding of domestic animals. He devoted much of the rest of his life to exploring its implications for human populations, which Darwin had only hinted at. In doing so, he ultimately established a research programme that came to embrace all aspects of human variation, from mental characteristics to height, from facial images to fingerprint patterns. This required inventing novel measures of traits, devising large-scale collection of data using those measures, and in the end the discovery of new statistical techniques for describing and understanding the data gathered.
Galton was interested at first in the question of whether human ability was indeed hereditary, and proposed to count the number of the relatives of various degrees of eminent men. If the qualities were hereditary, he reasoned, there should be more eminent men among the relatives, than among the general population. He obtained his data from various biographical sources and compared the results that he tabulated in various ways. This pioneering work was described in detail in his book Hereditary Genius[2] in 1869. He showed, among other things, that the numbers of eminent relatives dropped off when going from the first degree to the second degree relatives, and from the second degree to the third. He took this as evidence of the inheritance of abilities. He also proposed adoption studies, including trans-racial adoption studies, to separate out the effects of heredity and environment.
The method used in Hereditary Genius has been described as the first example of historiometry. To bolster these results, and to attempt to make a distinction between 'nature' and 'nurture' (he was the first to apply this phrase to the topic) he devised a questionnaire that he sent out to 190 Fellows of the Royal Society. He tabulated characteristics of their families, such as birth order and the occupation and race of their parents. He attempted to discover if their interest in science was "innate" or due to the encouragements of others. The studies were published as a book, English Men of Science: Their Nature and Nurture in 1874. In the end, it illuminated the nature versus nurture question, though it did not settle it, and provided some fascinating data on the sociology of scientists of the time.
Galton recognized the limitations of his methods in these two works, and believed the question could be better studied by comparisons of twins. His method was to see if twins who were similar at birth diverged in dissimilar environments, and whether twins dissimilar at birth converged when reared in similar environments. He again used the method of questionnaires to gather various sorts of data, which were tabulated and described in a paper "The History of Twins" in 1875. In so doing he anticipated the modern field of behavior genetics, which relies heavily on twin studies. He concluded that the evidence favored nature rather than nurture.
Galton invented the term eugenics in 1883 and set down many of his observations and conclusions in a book, Inquiries in Human Faculty and its Development.[3] He believed that a scheme of 'marks' for family merit should be defined, and early marriage between families of high rank be encouraged by provision of monetary incentives. He pointed out some of the dysgenic tendencies in British society, such as the late marriages of eminent people, and the paucity of their children. He advocated encouraging eugenic marriages by supplying incentives for the able to have children.
His ideas would greatly influence similar movements in many other countries. He cautioned, however, against the sorts of extreme proposals that the eugenics movement soon produced when it was taken up enthusiastically by socialists such as George Bernard Shaw, HG Wells, and their followers, who were enthusiastic about state compulsion and social engineering.
Galton's study of human abilities ultimately led to the foundation of differential psychology, the formulation of the first mental tests, and the scientific study of human intelligence. Many of his insights have taken many decades of research to verify; for example, his study of reaction time as a measure of intelligence was only vindicated a hundred years later, as was his assertion of a relationship between head size on intelligence (MRI measures are now known to correlate at approximately 0.4 with I.Q.).
Galton conducted wide-ranging inquiries into heredity. In the process he was able to refute Darwin's theory of pangenesis. Darwin had proposed as part of this theory that certain particles, which he called 'gemmules' moved throughout the body and were also responsible for the inheritance of acquired characteristics. Galton, in consultation with Darwin, set out to see if they were transported in the blood. In a long series of experiments in 1869 to 1871, he transfused the blood between dissimilar breeds of rabbits, and examined the features of their offspring. He found no evidence of characters transmitted in the transfused blood. Galton explicitly rejected the idea of the inheritance of acquired characteristics (Lamarckism), and was an early proponent of "hard heredity" through selection alone.
Galton came close to rediscovering Mendel's particulate theory of inheritance, but was prevented from making the final breakthrough in this regard because of his focus on continuous, rather than discrete, traits (now known as polygenic traits). He went on to found the Biometric approach to the study of heredity, distinguished by its use of statistical techniques to study continuous traits and population-scale aspects of heredity. This approach was later taken up enthusiastically by Karl Pearson and W.F.R. Weldon; together, they founded the highly influential journal Biometrika in 1901. (R.A. Fisher would later show how the biometrical approach could be reconciled with the Mendelian approach.) The statistical techniques that Galton invented (correlation, regression - see below) and phenomena he established (regression to the mean) formed the basis of the biometric approach and are now essential tools in all the social sciences.
Galton also devised a technique called composite photography, described in detail in Inquiries in Human Faculty and its Development, which he believed could be used to identify 'types' by appearance, which he hoped would aid medical diagnosis, and even criminology through the identification of typical criminal faces. However he was forced to conclude after exhaustive experimentation that such types were not attainable in practice.
Statistics, regression and correlation
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, which he elicited by his pioneering use of the questionnaire.
Galton invented the use of the regression line, and was the first to describe and explain the common phenomenon of regression toward the mean, which he first observed in his experiments on the size of the seeds of successive generations of sweet peas. In the 1870s and 1880s he was a pioneer in the use of normal distribution to fit histograms of actual tabulated data. He invented the Quincunx, a pachinko-like device, also known as the bean machine, as a tool for demonstrating the law of error and the normal distribution. He also discovered the properties of the bivariate normal distribution and its relationship to regression analysis.
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.
He also developed early theories of ranges of sound and hearing, and collected large quantities of anthropometric data from the public through his popular and long-running Anthropometric Laboratory. It was not until 1985 that this data was analyzed in its entirety.
Final years
In an effort to reach a wider audience, Galton worked on a novel entitled ‘Kantsaywhere’, from May until December of 1910. The novel described a utopia organized by a eugenic religion, designed to breed fitter and smarter humans. His unpublished notebooks show that this was an expansion of material he had been composing since at least 1901. He offered it to Methuen for publication, but they showed little enthusiasm. Galton wrote to his niece that it should be either “smothered or superseded”. His niece appears to have burnt most of the novel, offended by the love scenes, but large fragments survive (see [4]).