Water-level task

The water-level task is an experiment in developmental and cognitive psychology developed by Jean Piaget. The water-level task is an experiment in developmental and cognitive psychology developed by Jean Piaget. The experiment attempts to assess the subject's reasoning ability in spatial relations. To do so the subject is shown pictures depicting various shaped bottles with a water level marked, then shown pictures of the bottles tilted on different angles without the level marked, and the subject is asked to mark where the water level would be.