Of all the many blockheaded works of purported science perpetrated upon the American people, from William Ripley’s 1899 The Races of Europe to contemporary tracts advancing “the one true secret to beating cancer,” few have been more pernicious in effect than a slim monograph published in 1912, entitled The Kallikak Family: A Study in the Heredity of Feeble-Mindedness.

Written by the psychologist Henry Herbert Goddard (1866–1957), the book describes investigations he undertook while director of research at New Jersey’s Vineland School for the “feeble-minded” from 1906 to 1918. An ambitious farmer’s son from Maine, Goddard first made his scientific bones as an early adopter of intelligence testing, which he used to classify Vineland School wards as “morons,” “imbeciles,” or “idiots,” in descending order of mental acuity. Those classifications, and their attendant IQ points, were still in use in the late 1960s, when I took a college course in “abnormal psychology” and was compelled to memorize the numbers that bracketed each category of mental retardation as surely, it seemed, as ranges of temperature define tropical, temperate, and frigid climates. (Goddard had a predilection for inventing words from the Greek, and “moron,” his enduring contribution to our language, is said to be drawn from a word meaning foolish.)

Goddard’s larger fame, however, came with the publication of the Kallikak book, which traced the family history of a Vineland ward named Deborah, who was admitted at age eight in 1897, and on whom Goddard would bestow a stage name that rammed the Greek word for “beauty” (kallos) against the Greek word for “bad” (kakos), indicating that the family to whom Deborah Kallikak (her real surname has never been revealed) owed her descent ran in two strains of “blood,” one beautiful and one bad, the former having its headwaters in the marriage of Martin Kallikak, a Revolu­tionary War veteran, to “a lawful wife” in the late 1770s, and the latter stemming from the man’s earlier dalliance with a “feeble-minded” barmaid.

According to the devoted young women whom Goddard sent out to research these two lines, of 480 descendants of the “bad seed,” 143 were “feeble-minded” and only 46 could be decreed “normal,” the rest being declared “unknown or doubtful.” By contrast, among “the legitimate children” and their descendants, researchers found “nothing but good representative citizenship . . . men and women prominent in every phase of social life.” The study became celebrated and poisonous science, first because Goddard issued his findings during one of those periods in which American “natives” grow convulsively concerned about the mongrelization of the nation’s pedigree through immigration. Second, Goddard linked his findings to Mendelian notions of genetics that had just been brought to the world’s admiring attention, Goddard saying that his findings were proof that intelligence was, in Mendelian terms, a “unitary trait,” controlled by one gene, which could be either kallos or kakos. Wrote Goddard, “No amount of education or good environment . . . can change a red-haired stock into a black-haired stock.”

That understanding would nourish a vile American eugenics movement and guide social policy for decades, as resourceful researchers turned up other Kallikak-like families, as well as evidence that more than half of the southern and eastern Europeans coming through Ellis Island were, in Goddard’s own finding, “moron grade.” By 1938 there were compulsory sterilization laws in 30 states and nearly 30,000 citizens had been rendered unfruitful by court order, including Carrie Buck, whose case against the State of Virginia was carried to the Supreme Court, where Oliver Wendell Holmes, writing for the majority, said, “We have seen more than once that the public welfare may call upon the best of citizens for their lives. It would be strange if it could not call upon those who already sap the strength of the State for these lesser sacrifices.” Buck v. Bell, along with Goddard’s Kallikak findings, were later cited in Germany as supportive of Rassenhygiene laws.

Goddard did repent of some Kallikak findings and conclusions but continued to lie about at least one critical matter: that he had diagnosed Martin Kallikak’s paramour as defective on the basis of evidence. In fact, he never knew who she was, relying for his judgment on 125-year-old gossip. As for Deborah Kallikak, she lived at the Vineland School until she died, at 89, in 1978. She is variously reported to have been charming, stubborn, skilled in crafts, musical, a capable nurse’s aide and schoolteacher, and articulate (her letters survive). Her photographs show her to be pretty. When all this was later pointed out to Goddard, he acknowledged that she seemed normal—morons often do, he said. But the fact was that she had scored below the norm on an intelligence test when she was a teenager, and this was a scientific finding that could not be obviated or altered by any subsequent perception or emotion.

Our story on scientific findings and subsequent perception and emotion begins here.

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