Kallikak Family

The Kallikak family is a pseudonym for a family involved in a psychological study of the hereditary aspects of intelligence.

The history of intelligence testing in the United States has been troublesome from the beginning. Although psychologists attempted to conduct legitimate research and apply psychological knowledge to the study of intelligence, some of the early work was quite unscientific and led to dubious results.

One case involved the descendants of an anonymous man referred to as Martin Kallikak. This man produced two different lines of descent, one with a supposedly “feebleminded” bar maid with whom he had had sexual relations while a young man in the army, and one with the woman he married later in life, reputed to be an honest Quaker woman from an upstanding family. The offspring from the two women generated two lineages that could not have been more different. The pseudonym Kallikak was taken from two Greek words: kallos, meaning beauty (referring to the descendants of the Quaker woman) and kakos, mean-ing bad (referring to the descendants of the bar maid).

The psychologist Henry Goddard (1866–1957) investigated these two groups over a two-year period. According to psychology historian David Hothersall, Goddard discovered that the inferior branch of Martin Kallikak's family included “46 normal people, 143 who were definitely feebleminded, 36 illegitimate births, 33 sexually immoral people, 3 epileptics, and 24 alcoholics. These people were horse thieves, paupers, convicts, prostitutes, criminals, and keepers of houses of ill repute. On the other hand, the Quaker side of the family included only 3 somewhat mentally degenerate people, 2 alcoholics, 1 sexually loose person, and no illegitimate births or epileptics.”

These patterns of behavior were believed to be the results of heredity, rather than environment, even though the two environments were radically different. Goddard also believed that intelligence was determined by heredity, just like the inclination toward prostitution, theft, and poverty.

Goddard was also a supporter of the eugenics movement in the United States. One of the solutions that he proposed for controlling the creation of the so-called defective classes was sterilization, which he advocated as being as simple as having a tooth extracted. Later in his career, Goddard retracted some of his earlier conclusions and maintained that, although intelligence had a hereditary basis, morons (at that time a technical term that Goddard himself coined) might beget other morons, but they could be educated and made useful to society. Today we understand intelligence to be influenced by both genetics and environmental factors.

See also Jukes family ; Nature-nurture controversy .



Bashford, Alison, and Levine, Philippa. The Oxford Handbook of the History of Eugenics. New York: Oxford University Press, 2010.

Goddard, Henry Herbert. The Kallikak Family: A Study in the Heredity of Feeble-Mindedness. New York: Macmillan, 1927.

Gould, Stephen Jay. The Mismeasure of Man. New York: Norton, 1981.

Smith, David. Minds Made Feeble: The Myth and Legacy of the Kallikaks. Rockville, MD: Aspen Systems, 1985.

Stern, Alexandra. Eugenics Nation: Faults and Frontiers of Better Breeding in Modern America, 2nd ed. Oakland: University of California Press, 2016.