Piaget: conservation and the concrete operational stage
A 4-year-old insists a tall, narrow glass holds more juice than a short, wide glass, even after watching the same juice poured between them. Mastering this task would mark her entry into which stage?
Answer A: explanation for every choice
Correct. Conservation, understanding that quantity stays the same despite changes in shape, is the hallmark of the concrete operational stage (about ages 7–11).
Preoperational is her current stage (about ages 2–7), marked by symbolic thought, egocentrism, and lack of conservation.
The sensorimotor stage (birth to about age 2) is when object permanence develops.
The formal operational stage (adolescence) brings abstract and hypothetical reasoning, which comes after conservation.
Reviewed 2026-11-05 by a medical student. Spot an error? Report it with question ID ps33.