In this video clip, David Deutsch says that it’s not enough to just make big promises. People believe when there is proof, but proof can be more than facts and studies—it can also be common sense or things people already understand. Like a jury that believes the best story instead of just adding up evidence, customers are swayed by stories. Good advertising is like telling a story: the story of the product, what it can do for the buyer, or how it was created. In the end, the best story wins, because it makes people believe more than just bold promises.