In studying the process of problem solving, the only gateway to finding out what a subject is thinking, and how he is approaching the problem, is metacognition. Metacognition, put simply, is thinking about thinking.

When attempting to solve a problem, the first decision one must make is whether or not he has encountered a similar problem before. If he has, his best choice is to exercise reproductive thought, and recall his strategy for solving the similar problem previously. If this is a new problem, he must think productively. In productive thinking, brainstorming plays a more important part in arriving at an answer.

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