In this chapter, Cain examines how introverts can play the role of extroverts when necessary. She discusses the work of Brian Little, a former Harvard professor who devised the Free Trait Theory. Little believes people are born with certain fixed traits, but also possess so-called free traits that allow them to act out of character and adapt when doing something they love. Little himself is extremely introverted but taught himself how to act like an extrovert for his work. He gives dynamic speeches at universities, but then recharges his batteries by watching ships traverse a river. He has even resorted to hiding in the men’s room at times.

Such taking on the part of extroverts can be very convincing, but Cain wonders whether every introverted person can pull it off. The research of psychologist Richard Lippa uncovered “self-monitoring,” the ability to adapt well to a given situation. He determined there are two types of people: “low self-monitors (LSMs) and high self-monitors (HSMs)” (213). The former have trouble adapting and behave more according to their internal makeup, while the latter are skilled at adapting. The ability to do so goes back to the Free Trait Theory—people adapt for things they truly love or believe in.