Intelligence in Historical Perspective

Historical Perspectives on Intelligence

• Early research in intelligence can be linked to Sir Francis Galton and Alfred Binet.
• Sir Francis Galton (1822 - 1911) emphasized the role of genetics and heredity in intelligence, proposing that genius runs in families.
• Galton conducted physical and sensory measurements (reaction speed, hand strength, sensory acuity, skull size) to explore his theories.

Eugenics in South Africa

• In the 1920s, South Africa formed the Eugenics and Genetics Standing Committee within the SAAAS, which promoted racial categorization and oppression.

Alfred Binet’s Contributions

• Alfred Binet (1857 - 1911) created the first practical intelligence test in 1905 aimed at assessing school children's mental abilities.
• Binet's method involved comparing a child's performance against established age norms determined by testing multiple children across age groups.
• Introduced the concept of mental age (MA) to gauge intelligence, noting fast learners answered like older peers while slow learners resembled younger children.

William Stern and IQ

• William Stern developed the Intelligence Quotient (IQ) formula: IQ = (MA/CA) x 100, where CA is chronological age.
• This approach enables limited cross-age comparisons of intelligence.

Stanford-Binet Test

• Lewis Terman revised Binet's test for use in the USA, creating the Stanford-Binet Test, primarily verbal-based, yielding a single score.
• The test became a standard measure for clinical psychology, psychiatry, and educational counseling, based on the idea of intelligence being largely hereditary.
• The concept of MA is not useful for adults; normative scores provide better performance comparisons.

David Wechsler’s Innovations

• David Wechsler introduced a multi-faceted approach to intelligence testing through measures like WAIS-R, WISC-IV, and WPPSI-R.
• He developed scales assessing verbal and performance IQ to account for individuals with verbal deficits.
• The structure of the WISC-IV consists of four indexes contributing to a comprehensive Full Scale IQ.

Types of Intelligence Testing in South Africa

• Senior South African Individual Scale (SSAIS-R) for ages 7-16 years.
• Junior South African Individual Scale (JSAIS-R) for ages 3-7 years.
• South African Wechsler Adult Intelligence Scale (SAWAIS) for ages 16-69 years.
• Socio-economic Deprivation Questionnaire aids psychologists in contextualizing scores based on background.

Nature of Intelligence

• Split into two main approaches:
  • Psychometric Approach: Focuses on the structure of intelligence and underlying competencies.
  • Cognitive Processes Approach: Examines specific thought processes influencing intelligence.

Psychometric Approaches

• Psychometrics utilizes statistical methods to understand psychological tests and determine mental abilities.
• Factor Analysis organizes large data sets into clusters based on correlations, aiding comprehension of intelligence structures.

The ‘g’ Factor Theory

• Charles Spearman posited the existence of a general intelligence factor ('g') influenced by specific skills ('s').
• 'g' serves as a predictor for academic and job performance, highlighting its significance in cognitive studies.

Horn-Cattell's Two-Factor Theory

• Divides general intelligence ('g') into crystallized intelligence (gc), stable knowledge, and fluid intelligence (gf), which pertains to problem-solving and tends to decline with age.

Louis Thurstone’s Primary Mental Abilities

• Proposed seven distinct mental abilities challenging the singular 'g' factor concept, emphasizing diverse cognitive skills.

Carroll’s Three-Stratum Model

• Established through extensive factor analysis, this model categorizes intelligence into three levels: general ('g'), broad abilities (gf, gc, plus other functions), and narrow specific skills.

Cognitive Process Approaches

• Focus on the information-processing aspects of intelligence; Robert Sternberg's Triarchic Theory divides cognitive skills into metacomponents, performance components, and knowledge-acquisition components.
• Sternberg identifies three intelligence types: analytical (problem-solving), practical (everyday skills), and creative (adaptive thinking).

Howard Gardner’s Multiple Intelligences

• Defines eight distinct intelligences:
  • Linguistic
  • Logical-Mathematical
  • Spatial
  • Musical
  • Bodily-Kinesthetic
  • Interpersonal
  • Intrapersonal
  • Naturalistic
  • Existential

Emotional Intelligence

• Comprises abilities to accurately perceive, respond to, and regulate emotions.
• The Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT) assesses emotional intelligence through four components:
  • Perceiving Emotions
  • Using Emotions to Facilitate Thought
  • Understanding Emotions
  • Managing Emotions