Cattell, Raymond B., 1905-, American psychologist, b. Staffordshire, England. He came to the United States in 1937 and served as research professor at the Univ. of Illinois (1944-73). He maintained that human personality consisted of 46 surface traits, from which could be derived 16 source traits that constitute personality. From this theory he developed (1950) the Sixteen Personality Factor Questionnaire. He also developed an influential theory suggesting that intelligence should be divided into fluid, or innate, ability and crystallized, or culturally constituted, intelligence. A prolific writer, his works include Abilities: Their Structure, Growth, and Action (1971) and Personality and Learning Theory (2 vol., 1979-80).