 From the late 19th century, the American school, led by researchers such as H. H. Goddard (1866–1957), Lewis Terman (1877–1956), and Robert Yerkes (1876–1956), transformed these tests into tools for measuring inherited mental ability.They attempted to measure people's intelligence with IQ tests, to demonstrate that the resulting scores were heritable, and so to conclude that people with white skin were superior to the rest.It proved impossible to design culture-independent tests and to carry out testing in a fair way given that people came from different backgrounds, or were newly arrived immigrants, or were illiterate.