Another interesting part of first impressions is that people act how others expect them to act. This is called a self-fulfilling prophecy. Research by Snyder and Swann supports this idea (1978). In that study, partners played a game together. The partners did not know one another, so the researchers told each player about his partner. Sometimes they said positive, or good, things about a partner. Sometimes they said negative, or bad, things. The result of the study showed that players acted friendly when they expected their partners to be friendly, but they acted unfriendly when they expected their partners to be unfriendly. The players' expectations influenced how they acted toward one another.