One major feature of adult thinking, beginning in adolescence and becoming more firmly rooted in early adulthood, is the tendency to analyze verbal statements and to evaluate their validity as formal propositions. When faced with a problem, adults immediately search for possibilities. They examine the situation carefully, look for all possible solutions, and then analyze those options to determine which is the best possible answer. They follow the steps of scientific reasoning. (See Chapter 47 for a discussion of problem solving.)

Another notable component of adult thought is the acquisition of specific knowledge combined with a greater capacity for information processing. Both of these features, plus greater speed and accuracy, contribute to the reasoning abilities needed in problem solving. With improvement in memory, for example, adults solve problems more readily by remembering similar problems and the ways in which they were solved.

Several theories have been proposed to explain changes in adult thinking that move beyond Piaget’s work. These theoretical endeavors have examined a person’s improved ability to engage in reflective thinking. New research has also probed the dimensions of postformal thought, which includes emotion and practical experience.