How could I be so stupid? Intelligent individuals, by virtue of being smart, often think that they cannot behave stupidly, but that is precisely what leads them down the garden path to behaving in just such a manner.

• Author: Sternberg, Robert J.
• Position: Psychology

HOW MANY TIMES have you said to yourself, "How could I be so stupid?" Chances are, you really meant it, at least at the time. Why do smart people act stupidly? What, if anything, can they do about it?

If it is any consolation, some of the most powerful people in the world have lived to rue their own stupidity. In my lifetime, one president (Richard Nixon) had to resign to escape impeachment, while another (Bill Clinton) did face impeachment proceedings because he simply shrugged off the public disgrace of an affair with an intern. Andrew Fastow, former chief financial officer of Enron and a graduate of the university where I teach (Tufts), is in prison. Kenneth Lay and Jeffrey Skilling, former chief executive officers at Enron and convicted for being instrumental in its bankruptcy, were well educated. Lay has a doctorate in economics from the University of Houston; Skilling, an MBA from Harvard University. Clearly, being smart and well educated is no protection from stupidity. What do all of these people have in common?

First, we must distinguish stupidity, as the word is commonly used, from lack of intelligence, as measured by conventional tests and level of education. One would not say of any of these people that they are unintelligent. Yet, one might reasonably put forth that, on certain occasions, they behaved stupidly. Here, one is distinguishing between a long-term trait (intelligence) and a short-term state (acting stupidly). Unfortunately for certain individuals, that short-term state can begin to drag itself out over time. People who are unintelligent do not perform well in many tasks because they cannot. People who act stupidly do not perform well, but could if they wished to. That is, Nixon, Clinton, Fastow, Lay, and Skilling all had a choice. They chose to behave in stupid ways. They were smart, but did not show it in their actions.

When people act stupidly, there generally are two types of reasons for doing so. One is an error of omission, the other, of commission. Errors of omission typically are due to mindlessness. This term, popularized by Harvard psychologist Ellen Langer, refers to our behaving in ways that show a lack of critical thinking. Here are a couple of examples from Langer's work.

In one study, a confederate of Langer's asked someone using a copy machine if she could interrupt. The request was made under either of two conditions. In one condition, the confederate simply asked to use the machine. In the other, the confederate asked to use the machine because, she said, she needed to make copies. Note that the reason given is totally uninformative. Why else would she use a copy machine except to make copies'? Yet, the user of the machine was more likely to let the confederate interrupt her if she was given this reason, despite its being totally lacking in relevant...