ABSTRACT
In Piaget's famous demonstrations of failure to conserve, the child, entrapped by a compelling percept, judges accordingly in disregard of a rule that in other contexts he may 'know'. Young children are known to be selectively sensitive to novelty and therefore uncertainty. Bowerman used replacement sequences to argue for the psychological unity of a constituent in early language development. French has related children's early preference for the agentive relation of subject to verb to the perceptual salience of an initiator of action. If young children imagine the situation that a sentence describes, then they might treat these representations in the same way that they would treat an actual event. Children who show 'random' performance may actually be trying out different solutions. One can now resolve the paradox that children may use information in their own speech that they disregard in comprehension.
