Piaget's Conservation Experiments

Conservation is the understanding that the quantity of something remains the same even when its appearance changes. Piaget argued that children in the pre-operational stage (aged 2–7) cannot conserve, while children in the concrete operational stage (aged 7–11) can. Conservation is one of the most famous and most studied aspects of Piaget's theory.

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What is Conservation?

Conservation involves understanding that certain properties of objects (such as number, volume, mass, or length) remain unchanged even when the object's appearance is altered, as long as nothing has been added or taken away.

For example:

• If you pour water from a short, wide glass into a tall, thin glass, the amount of water remains the same — even though it looks different
• A pre-operational child will typically say the tall glass has more water because the water level is higher

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Piaget's Conservation Tasks

Piaget developed a series of tasks to test conservation across different dimensions:

Conservation of Number