What is intelligence? Psychometric theories
Intelligence is the ability to understand the world, think clearly and use resources well when facing challenges.
Psychometric (factor) approach
This approach measures intelligence with tests and looks for the abilities (factors) behind scores.
- Alfred Binet: first test; intelligence as one general ability.
- Charles Spearman, two-factor theory: a general factor (g) used in all tasks plus many specific factors (s) for single tasks.
- Louis Thurstone, primary mental abilities: seven separate abilities: verbal meaning, number, word fluency, space, memory, perceptual speed, reasoning.
- Arthur Jensen: Level I (associative learning, like rote memory) and Level II (cognitive, higher thinking).
- J.P. Guilford, structure-of-intellect: every ability = operation × content × product, giving about 180 abilities.
Multiple intelligences (Howard Gardner)
Gardner said intelligence is not one thing. There are separate, equal kinds:
- Linguistic: using words well (poets, speakers).
- Logical-mathematical: reasoning and numbers (scientists).
- Spatial: pictures in the mind (pilots, artists).
- Musical: rhythm and tune (singers).
- Bodily-kinaesthetic: skilful use of the body (dancers, athletes).
- Interpersonal: understanding others (teachers, leaders).
- Intrapersonal: understanding oneself.
- Naturalistic: noticing patterns in nature (farmers, botanists).
Triarchic theory and the PASS model
Sternberg's triarchic theory
Intelligence helps us adapt, shape and choose our surroundings. It has three parts:
- Componential (analytical): breaking a problem into parts; includes knowledge-gaining, meta (planning) and performance parts.
- Experiential (creative): using past experience in new ways.
- Contextual (practical): street smartness; dealing with daily life.
PASS model (J.P. Das, Jack Naglieri, John Kirby)
Intelligence depends on three brain systems:
- Arousal/Attention: being alert and focusing.
- Simultaneous and Successive processing: seeing things as a whole at once, and handling things in a fixed order (like reciting a table).
- Planning: deciding what to do, doing it and checking.
Das and Naglieri built the Cognitive Assessment System (CAS) from it.
Individual differences in intelligence
Heredity and environment: identical twins raised together have very similar IQs; children adopted into rich homes gain in IQ. So both genes and surroundings matter.
IQ
Mental age (MA) is the level of ability compared with others of that age. Chronological age (CA) is the real age. IQ = MA ÷ CA × 100 (William Stern). If MA = CA, IQ = 100.
- About two-thirds of people score between 85 and 115; the average is 100.
- 130 and above: intellectually gifted.
- Below about 70 along with trouble in daily living: intellectual disability (mild 55-69, moderate 40-54, severe 25-39, profound below 25).
Types of tests
Individual or group; verbal, non-verbal or performance; culture-fair or culture-biased.
Giftedness
Gifted children show high ability, creativity and deep interest. Talent is outstanding skill in one area.
Culture and intelligence
Each culture values some skills more. Technological intelligence, valued in technologically advanced societies, stresses attention, speed, generalisation and abstract thinking. Indian thought values integral intelligence: connecting with people and the world. It includes cognitive capacity, social competence, emotional competence and entrepreneurial competence. The Sanskrit word buddhi includes wisdom, self-knowledge and good judgement, not just speed.
Emotional intelligence
Emotional intelligence (EI) is the ability to notice, understand and manage one's own feelings and those of others (Salovey and Mayer; made popular by Daniel Goleman). EQ is its measure.
Signs of high EI:
- Knowing your feelings (self-awareness).
- Managing your feelings, like calming anger.
- Motivating yourself.
- Sensing others' feelings (empathy).
- Handling relationships well.
EI helps in school, jobs and friendships. Schools can teach it through life-skill lessons.
Try it at home
List eight people you know. For each, write which of Gardner's eight intelligences is their strongest. You will see that people who are not good at studies may be very smart in another way.
Key formulas and definitions
- IQ = (Mental age ÷ Chronological age) × 100
- Spearman: g (general) + s (specific)
- Thurstone: 7 primary mental abilities
- Guilford: operation × content × product ≈ 180 abilities
- Gardner: 8 intelligences
- Sternberg: componential + experiential + contextual
- PASS: Planning, Attention-arousal, Simultaneous-Successive
- IQ 130+: gifted; below 70: intellectual disability
Worked examples
1. A 10-year-old has a mental age of 12. Find the IQ.
IQ = MA ÷ CA × 100 = 12 ÷ 10 × 100 = 120. This is above average.
2. An 8-year-old has a mental age of 6. Find the IQ and say what it means.
IQ = 6 ÷ 8 × 100 = 75. It is below average but above the 70 line, so it is not intellectual disability by score alone.
3. A child has IQ 110 and real age 10. What is the mental age?
MA = IQ × CA ÷ 100 = 110 × 10 ÷ 100 = 11 years.
4. Kavya cannot solve textbook sums but runs her family shop smartly. Which part of Sternberg's theory is strong in her?
Contextual (practical) intelligence: street smartness in dealing with daily life.
5. A child recites a phone number digit by digit. Which PASS process is this?
Successive processing: handling items in a fixed order, one after another.
6. Rahul notices when his friend is upset and says the right thing. Which idea?
Emotional intelligence (empathy), also Gardner's interpersonal intelligence.
Common mistakes
- Thinking IQ is the same as intelligence. IQ is just one score from one kind of test.
- Mixing interpersonal (understanding others) with intrapersonal (understanding yourself).
- Calling anyone with IQ below 70 intellectually disabled. Trouble in daily living (adaptive behaviour) must also be present.
- Thinking one culture's idea of intelligence fits all. Integral and technological intelligence value different skills.