You're feeling the power of social proof when you order the same appetizer as everyone else at the table, even though you've never eaten a ridge gourd.
Robert Cialdini says social proof equips us with a "wonderful kind of automatic-pilot device" that spares us mistakes—but also leaves us vulnerable to marketers.
Social proof explains why baristas salt the tip jar; why publishers splash "best-seller" across book covers; and why manias for products like mortgage derivatives and Cabbage Patch Dolls occur.
Want to persuade someone? Tout the number of customers you have or all the great reviews you've gotten.
