who developed the first intelligence test and for what reason
Alfred Binet Alfred Binet (French: [binɛ]; July 8, 1857 – October 18, 1911) was a French psychologist who invented the first practical IQ test, the Binet–Simon test.[2] In 1904, the French Ministry of Education asked psychologist Alfred Binet to devise a method that would determine which students did not learn effectively from regular classroom instruction so they could be given remedial work. Along with his collaborator Théodore Simon, Binet published revisions of his test in 1908 and 1911, the last of which appeared just before his death.
Fluid and crystallized intelligence Fluid and crystallized intelligence were originally identified by Raymond Cattell.[3] Concepts of fluid and crystallized intelligence were further developed by Cattell's student, John L. Horn. Since Cattell's and Horn's publications, the concepts of fluid and crystallized intelligence have become so ingrained in the field of intelligence that they are no longer routinely attributed to Cattell or Hornâ€”much as Cattell's scree plot became ingrained in the practice of factor analysis or Freud's concept of the subconscious is ingrained in psychology and in the public's perceptions of the mind.