Throughout my life as a social psychologist, I have had two major goals: to design and conduct controlled experiments that shed light on how the human mind works, and to make discoveries that might be useful to people and perhaps even improve society. When I was about to enter graduate school, I had stars in my eyes so, understandably, the second goal was far more prominent than the first. However, by the time I earned my PhD, I had discovered that, as a scientist, there is no way to do good in the world without first being able to do good research.
My great good fortune was that I entered Stanford as a student the same year that Leon Festinger joined the faculty as a professor. At that time, Festinger was developing his theory of cognitive dissonance, which proposed that when a person simultaneously holds two contradictory cognitions, he or she experiences an unpleasant feeling of discomfort (dissonance). The person is motivated to reduce that dissonance by altering one or both cognitions, bringing them into consonance. This simple theory led us to make predictions about human behavior that were bold, exciting, and innovative.
For example, in the first experiment I ever designed, Jud Mills and I demonstrated that people who went through a severe initiation to join a group later liked the group better than those who went through a mild initiation. We didn't try to convince people that their group was terrific; rather, we set up a situation where they convinced themselves that the group was terrific. The cognition “I went through hell and high water to get into this group” was dissonant with the fact that the group was actually pretty boring. Therefore, following a severe initiation, they were inclined to convince themselves that those boring group members were quite charming. The people who didn't have to go through a severe initiation saw the group for what it was.
In another experiment, my students and I showed that children who were threatened with severe punishment if they played with a forbidden but attractive toy were eager to play with it anyway as soon as they had the chance.