During which stage do children start understanding the concept of reversibility?

The concept of reversibility is a key cognitive development milestone observed in children during the Concrete Operational stage, which typically spans ages 7 to 11. At this stage, children begin to think logically about concrete events and understand that certain operations can be reversed, meaning they can mentally undo actions or processes.

For instance, if a child sees that water can be poured into a different container and retains the same amount, they understand that pouring it back into the original container will return it to its previous state. This understanding reflects their ability to think about transformations in a more sophisticated way, demonstrating cognitive growth beyond the limitations of earlier stages.

In contrast, during the Preoperational stage, which occurs before the Concrete Operational stage, children tend to think symbolically and are often unable to grasp the idea of reversibility. They focus on appearances rather than underlying principles. Thus, reversibility is not a characteristic of that stage. The other stages, such as Formal Operational and Sensorimotor, involve different cognitive processes that do not yet prioritize understanding reversibility in relationships and operations in the concrete, logical manner seen in the Concrete Operational stage.