What are Piaget's stages of cognitive development?

Piaget's Stages of Cognitive Development

Jean Piaget, a Swiss psychologist, proposed that children's cognitive development occurs in four universal, sequential stages. Each stage represents a qualitatively different way of thinking and understanding the world.

The Four Stages

1. Sensorimotor Stage (Birth to 2 years)
• Infants learn through sensory experiences and manipulating objects.
• Key milestone: Object permanence (understanding that objects exist even when not seen).
• Preoperational Stage (2 to 7 years)
• Children begin to use language and think symbolically.
• Thinking is egocentric and lacks logical operations.
• Concrete Operational Stage (7 to 11 years)
• Logical thinking develops, but is limited to concrete objects.
• Children understand concepts like conservation and reversibility.
• Formal Operational Stage (12 years and up)
• Abstract and hypothetical thinking emerges.
• Adolescents can reason logically about abstract propositions.

---

Worked Example: Conservation Task

Scenario:
A child is shown two identical glasses with equal amounts of water. The water from one glass is poured into a taller, thinner glass.

Question:
Does the child understand that the amount of water remains the same?

Step-by-Step Reasoning:

• Preoperational Stage (2-7 years):
• The child focuses on the height of the water and says the taller glass has more, failing to understand conservation.
• Concrete Operational Stage (7-11 years):

Mathematical Representation:

If $V_1 = V_2$ (initial volumes), after pouring:

$$ V_1 = V_2 implies \text{No change in quantity, only in shape} $$

Takeaways