Sticky ideas have to carry their own credentials. We need ways to help people test our ideas for themselves — a “try before you buy” philosophy for the world of ideas. When we’re trying to build a case for something, most of us instinctively grasp for hard numbers. But in many cases this is exactly the wrong approach. In the sole U.S presidential debate in 1980 between Ronald Reagan and Jimmy Carter, Reagan could have cited innumerable statistics demonstrating the sluggishness of the economy. Instead, he asked a simple question that allowed voters to test for themselves: “Before you vote, ask yourself if you are better off today than you were four years ago.”
Excerpt from: Made to Stick: Why some ideas take hold and others come unstuck by Chip Heath and Dan Heath