Influence: The Psychology of Persuasion

by Robert B. Cialdini

responding lies in its vulnerability to silly and costly mistakes; by reacting to only a piece of the available information (even a usually predictive piece), an individual increases the chances of error, especially when responding in an automatic, mindless fashion. The chances of error increase even further when other individuals seek to profit by arranging (through manipulation of trigger features) to stimulate a desired behavior at inappropriate times. Much of the compliance process (wherein one person is spurred to comply with another person’s request) can be understood in terms of a human tendency for automatic, shortcut responding. Most of us have developed a set of trigger features for compliance—that is, specific pieces of information that normally tell us when compliance with a request is likely to be correct and beneficial. Each of these trigger features for compliance can be used like a lever (of influence) to move people to agree with requests. Perceptual contrast—the tendency to see two things that are different from one another as being more different than they actually are—is a lever of influence used by some compliance