The influence of verbalization on problem-solving

The performance of subjects who were required to state reasons for moves while solving the Tower-of-Hanoi problem was compared to the performance of subjects who were not required to do so. In accordance with previous research it was found that stating reasons facilitated performance in reducing superfluous moves (errors). In addition it was found that the effect was due to a significant decrease in errors for moves close to important subgoals in a goal hierarchy of moves. The effect was explained in terms of the replacement of an automated process with controlled calculations for moves close to subgoals.