Foundations Of Cognitive Science


Klahr & Wallace (1982) felt that Piaget's theory of adaptation was not enough to explain cognitive development. They therefore developed a new theory, and posited that the mechanism behind development was generalization.

Klahr and Wallace divided generalization into three more specific categories: the time line, regularity detection, and redundancy elimination (Siegler, 1991). These three categories are described below.

The Time Line

The time line contains the data on which generalizations are based. In Klahr and Wallace's theory, whenever a system encounters a situation, it records the responses to that situation, the outcomes from those actions, and what new situations arose as a result. This recording of events ensures that the system keeps all the information about an even stored so that it can be referred back to in the future.

Regularity Detection

This process uses the contents of the time line to draw generalizations about experience. The system notes situations that are similar and notes where variations do not change the outcomes of situations.

Redundancy Elimination

This process improves efficiency by identifying processeing steps that are unecessary. In this way, it reaches a generalization that a less-complex sequence can achieve the same goal (Siegler, 1991).

Klahr and Wallace have developed a self-modifying computer simulation that models findings about children's thinking, and can demonstrate these processes in generalization.


  1. Klahr, D. (1982). Nonmonotone assessment of monotone development: An information processing analysis. In S. Strauss (Ed.), U-shaped behavioral growth. New York: Academic Press.
  2. Siegler, R. (1991). Children's thinking. Englewood Cliffs, NJ: Prentice-Hall.
  3. Vasta, R., Haith, M. M., & Miller, S. A. (1995). Child psychology: The modern science. New York, NY: Wiley.