Piaget's Theory of Cognitive Development

Piaget's Theory of Cognitive Development

Jean Piaget (1936) proposed that children's thinking develops through four stages, each with qualitatively different ways of understanding the world. His theory is one of the most influential in developmental psychology.

Piaget's Four Stages

Stage	Age	Key Features
Sensorimotor	0-2 years	Learns through senses and movement; develops object permanence (understanding that objects exist even when hidden)
Pre-operational	2-7 years	Uses language and symbols; egocentric (cannot see other perspectives); lacks conservation (does not understand that quantity stays the same when appearance changes)
Concrete operational	7-11 years	Can perform logical operations on concrete (physical) objects; understands conservation; less egocentric; can classify and seriate (order by size)
Formal operational	11+ years	Can think abstractly and hypothetically; can reason about possibilities, not just concrete reality; systematic problem-solving

Key Concepts

Schemas

• Schemas are mental frameworks that help us organise and interpret information
• Babies are born with simple schemas (grasping, sucking); these become more complex through experience
• Example: a child has a schema for "dog" — four legs, fur, tail. They apply this to all dogs

Assimilation and Accommodation

• Assimilation: fitting new information into an existing schema (e.g. seeing a poodle and calling it a "dog" — it fits the dog schema)
• Accommodation: changing an existing schema or creating a new one when new information does not fit (e.g. seeing a cat and initially calling it a "dog", then learning it is a different animal — the schema must change)
• Equilibration: the balance between assimilation and accommodation — when existing schemas cannot explain new experiences, there is disequilibrium, which motivates learning

Key Studies

Conservation experiment:

• Piaget showed children two identical rows of counters; when one row was spread out, pre-operational children said it had more counters
• They could not conserve — they focused on appearance (the row looks longer) rather than logic (nothing was added or removed)
• Concrete operational children could conserve correctly

Three Mountains Task (Piaget and Inhelder, 1956):

• Children sat at a table with a model of three mountains and were asked what a doll (sitting at a different position) could see
• Pre-operational children chose their own view — they could not take the doll's perspective
• This demonstrates egocentrism — the inability to see things from another person's point of view

Strengths of Piaget's Theory

• Highly influential — has transformed education; teachers now plan activities appropriate to children's developmental stage
• Research support — the conservation and Three Mountains studies provide evidence for the stages
• Practical applications — the idea of "readiness" (children can only learn certain things at certain stages) has shaped curriculum design
• Active learner — Piaget saw children as actively constructing knowledge, not passively receiving it

Weaknesses of Piaget's Theory

• Underestimated children's abilities — later research (e.g. McGarrigle and Donaldson, 1974 — "Naughty Teddy") showed that children can conserve earlier than Piaget claimed when the task is made more child-friendly
• Stage ages are not fixed — children progress through stages at different rates; some never reach formal operational thinking
• Cultural bias — Piaget studied mainly Western, middle-class children; stages may not be universal
• Underestimated social influences — Piaget focused on individual discovery; Vygotsky argued that learning is social and guided by adults
• Task demands — some of Piaget's tasks were confusing for young children, leading them to give wrong answers for reasons other than lack of ability

Exam Tips

• Know all four stages with ages and key features
• Be able to describe conservation and the Three Mountains Task in detail
• Use key terms: schema, assimilation, accommodation, equilibration, egocentrism, conservation
• For AO3: Piaget underestimated children — cite McGarrigle and Donaldson (1974) as a counter-study
• Common question: "Outline and evaluate Piaget's theory" — balance description (AO1) with evaluation (AO3)