According to Piaget, what is irreversibility?

Irreversibility, as defined by Piaget, refers to the cognitive limitation where a child cannot mentally reverse an action. For instance, a child might struggle to understand that if they pour juice from a tall, narrow glass into a short, wide cup, they cannot visualize the juice being poured back into the original glass without physically seeing it done. This inability to mentally trace back the steps of an action reflects a key aspect of cognitive development that Piaget studied, particularly during the preoperational stage. Children at this developmental level may understand that a process has occurred but cannot comprehend that it can be reversed, highlighting a fundamental distinction in logical thinking that matures with age and experience.

The other options involve perspectives and learning processes that do not directly relate to the specific cognitive limitation of irreversibility. For instance, the capacity to change one's perspective or learn through observation speaks more to social cognitive development and less to the core concept of being unable to mentally reverse an action.