"Power holders feel they need to be superior and competent. When they don't feel they can show that legitimately, they'll show it by taking people down a notch or two," Nathanael Fast, a social psychologist at the University of Southern California in Los Angeles, told the New Scientist. Fast led a series of experiments to investigate this theory. During one experiment, Fast and his colleague Serena Chen, of the University of California, Berkeley, “asked 90 men and women who had jobs to complete online questionnaires about their aggressive tendencies and perceived competence.” The results found that the respondents with the most aggressive characteristics held the most high-power jobs and, to use the scientific phrasing, had a chip on their shoulder. The found that the best way to temper these tendencies was flattery, showing that the aggressiveness stemmed from a hurt ego as much as from a feeling of threat to respondents’ power. “This might also explain why leaders of organisations both big and small surround themselves with yes-men and women,” he says.