Lesson 10 - Key Figures in Intelligence Testing in Humans

Francis Galton

Founder of psychometrics and early intelligence testing.

Francis Galton's Beliefs

Intelligence is largely hereditary.

James McKeen Cattell

Introducing mental tests and advancing psychometrics in the U.S.

James McKeen Cattell's Beliefs

Intelligence is inherited but can be influenced by environment; strong proponent of eugenics.

James McKeen Cattell's Impact

Helped establish psychology as a scientific field in America; early advocate for using psychology to assess human abilities.

Alfred Binet's Beliefs

Intelligence can improve with proper education; inheritance sets a limit, but environment matters.

Alfred Binet's Impact

Introduced the concept of 'intellectual age'; laid the groundwork for IQ testing and educational placement.

Charles Spearman

Came up with the theory of general intelligence (g factor).

Charles Spearman's Beliefs

Intelligence is a single, inherited general ability underlying all cognitive performance.

Charles Spearman's Impact

Introduced factor analysis; major influence on how intelligence is conceptualized and measured.

Henry Herbert Goddard

Translating the Binet-Simon scale to English; coined terms like 'moron.'

Henry Herbert Goddard's Beliefs

Intelligence is hereditary and feeble-mindedness should be controlled through institutionalization or sterilization.

Henry Herbert Goddard's Impact

Promoted IQ testing in immigration and eugenics policy; infamous for flawed 'Kallikak' study on hereditary intelligence.

Lewis Terman

Revising the Binet scale into the Stanford-Binet Intelligence Test.

Lewis Terman's Impact

Created the modern IQ test; launched longitudinal studies of gifted children ('Quiz Kids'), reshaping perceptions of high intelligence.

Robert Yerkes

Developing Army Alpha and Beta tests during WWI.

Robert Yerkes's Beliefs

Intelligence could be measured and applied for large-scale military assessment.

Robert Yerkes's Impact

Institutionalized psychological testing in the U.S. military; demonstrated utility of intelligence testing in applied settings.

David Wechsler

Creating the Wechsler Intelligence Scales (WAIS, WISC, WPPSI).

David Wechsler's Impact

Developed the most widely used intelligence tests today; introduced deviation IQ scoring.