Influence: The Psychology of Persuasion

by Robert B. Cialdini

Because we assume they will continue in the same direction, trends don’t just tell us where others’ behaviors have been and are now; we think they also tell us where others’ behaviors will be. Thus, trends give us access to a special and potent form of social proof—future social proof. When we asked the subjects in our study to predict the percentage of their colleagues who would conserve water at home over the next six years, only those who learned of the trend toward conservation predicted an increase. Indeed, many of these subjects predicted that by then, conservation would be the majority behavior. On the basis of these results, I no longer give my previous advice to individuals who have something new to offer that possesses limited current popularity. Rather than urging them away from the principle of social proof and toward one of the other principles, I ask if over a reasonable period of time, they have honest evidence of growing popularity. If yes, I recommend making that fact the central feature of their messaging—because, as their audiences will presume, such evidence will be an indicator of genuine worth and future popularity.