The Binet Tests

Binet, a psychologist and educator, founded the first French psychological
laboratory. He was a pioneer in the study of individual differences in abilities
and introduced intelligence tests that were quickly accepted and widely
used in Europe and the United States. His work stemmed from a commission
from the minister of education in Paris, who gave him the task of devising
a way to distinguish between idiocy and lunacy, as Esquirol had defined
them, and normal intelligence, so that handicapped students could be
given special instruction. Binet and Simon used many items that had been
developed by earlier examiners; the key advances they made were to rank
items in order of difficulty and to register results in terms of age-based cognitive
development. Their scale reflected the idea that intelligence was a
combination of faculties—judgment, practical sense, and initiative—and
contained measures related to memory, reasoning ability, numerical facility,
and object comparison.
Binet and Simon’s work demonstrated the feasibility of mental measurement,
assessing intelligence for the first time in general terms rather than
measuring its component parts. Binet revised the test in 1908, and another
revision was published in 1911, the year of his death. Advances in his basic design
led to the development of tests that could be used for all children (not
only those considered mentally limited) in assessing their “mental quotient,”
a ratio adapted by Lewis Terman of Stanford University. It was obtained by
dividing mental age (as determined through scores on a test) by chronological
age. Terman renamed it the intelligence quotient (IQ), and his 1916 version
of the Binet-Simon scale became known as the Stanford-Binet test, the
most common intelligence test administered in the United States during
the twentieth century. It was revised and updated in 1937, 1960, 1972, and
1986, when a point-scale format was introduced for the first time.