In this chapter, we will consider how we use the information in our memories to think. Thinking is the processing of information to solve problems and make judgments and decisions. Because these processes are important aspects of intelligent thinking, we will also consider intelligence testing and some of the controversies surrounding the concept of intelligence. We will start our discussion with the most basic, higher-level cognitive process—problem solving. You will be asked to solve several problems. You will learn more from these exercises if you try to solve each problem before reading about its solution.