" Notice that all of the foot-in-the-door experts seem to be excited about the same thing: You can use small commitments to manipulate a person’s self-image; you can use them to turn citizens into “public servants,” prospects into “customers,” prisoners into “collaborators.” And once you’ve got a man’s self-image where you want it, he should comply naturally with a whole range of your requests that are consistent with this view of himself. "

― Robert B. Cialdini , Influence: The Psychology of Persuasion