At its core, marketing has one job: to persuade. But persuasion is bigger than marketing; it’s one of the most powerful tools humans have, capable of building iconic brands, sparking global movements, and supporting the election of decisive political campaigns. 

Unfortunately, the way persuasion works is not fully understood. As a marketer, you can look at how many clicks your ad generated, or how many views your TV video received. But these are proxies for persuasion. How do you measure the emotional resonance of a funny ad? Or quantify the likelihood to vote from an inspiring speech? 

The true test of whether something persuades is typically not known until it’s too late: Someone decides to buy your product. Or they don’t. They cast a ballot for your candidate. Or they don’t. Which means marketers and campaign managers are constantly releasing communications with a big leap of faith, hoping that their work will persuade, with little data on what will actually work.