who developed the five factor theory of personality
Big Five personality traits The initial model was advanced by Ernest Tupes and Raymond Christal in 1961,[17] but failed to reach an academic audience until the 1980s. In 1990, J.M. Digman advanced his five-factor model of personality, which Lewis Goldberg extended to the highest level of organization.[18] These five overarching domains have been found to contain and subsume most known personality traits and are assumed to represent the basic structure behind all personality traits.[19]
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.