Alfred Binet
July 8, 1857 — Nice, France
Alfred Binet was a French psychologist who, together with Théodore Simon, invented the first practical intelligence test — laying the groundwork for modern psychometrics and changing how the world thinks about the mind.
Early Life and Education
Born Alfredo Binetti on July 8, 1857 in Nice, Binet was raised primarily by his mother after his parents separated. He moved to Paris, where he studied law before being drawn to the emerging science of psychology. Largely self-taught in his new field, he haunted the Bibliothèque nationale de France, reading voraciously in neurology, psychology, and philosophy. His early work focused on hypnosis and abnormal mental states, but he gradually shifted toward more rigorous experimental methods. In 1891 he joined the Laboratory of Experimental Psychology at the Sorbonne, where he would spend the rest of his career, eventually serving as director from 1895 until his death.
The Binet-Simon Scale
In 1904, the French Ministry of Public Instruction asked Binet to develop a method for identifying children who might need special schooling. Working with psychiatrist Théodore Simon, Binet devised a series of tasks ranging from simple commands to abstract reasoning problems, normed against what children of different ages could typically perform. The result — published in 1905 as the Binet-Simon Scale — was the world's first practical intelligence test. It was revised in 1908 and again in 1911, the year of Binet's death. The concept of a "mental age" emerged directly from this work: a child's score was expressed as the age level of the typical child who performed at that level.
Did You Know?
Binet was deeply troubled by the idea of a fixed, innate intelligence. He explicitly warned against using his test to label children as permanently limited, writing that it measured current ability, not destiny. He feared — correctly, as it turned out — that his test would be misused to justify deterministic theories of intelligence he rejected.
Legacy in Intelligence Testing
Binet's scale was adapted for American use by Lewis Terman at Stanford in 1916, yielding the Stanford-Binet test — one of the most widely used intelligence tests in history. The concept of the Intelligence Quotient (IQ), coined by German psychologist William Stern, grew from the mental-age framework Binet pioneered. Ironically, the mass intelligence-testing movement that swept the United States in the early 20th century used Binet's tools in ways he specifically opposed: to permanently classify individuals by innate capacity. Beyond intelligence testing, Binet conducted pioneering research on memory, suggestibility, and what he called "individual psychology." He published over 200 books, articles, and reviews. He died in Paris on October 18, 1911, at 54.