Two experiments used a formal model of developmental discontinuity derived from catastrophe theory to test whether the transition from Rule I to Rule II on the balance scale task proceeds discontinuously from ages 6 to 10, focusing on five catastrophe flags. Found that bimodality, inaccessible region, hysteresis, and sudden jump were clearly…

Discusses hierarchical complexity of tasks as a way of conceptualizing information in terms of the power required to complete a task, and its implications for developmental psychology and information science. Provides an analytic solution to the definition of developmental stages and allows for the possibility within the science of scaling the…