What do the weird resurgence of Hush Puppies shoes, the sudden drop in New York City's crime rate, the steady rise in teen smoking, and the revolutionary success of Sesame Street have to do with proclaiming the gospel? A lot, if you take to heart Malcolm Gladwell's thesis in his bestseller, The Tipping Point: How Little Things Can Make a Big Difference.Gladwell, a staff writer for The New Yorker, has taken principles of epidemiology (the study of how diseases spread) and translated them into strategies for understanding the life cycle of cultural trends. Just like disease epidemics, he says, ideas and messages have "tipping points"—dramatic moments when, all at once, they explode upon a society and "infect" it. Studying these phenomena could help us "start and control positive social epidemics of our own."CT advisory editor Michael Cromartie spoke to Gladwell at his New Yorker office in Manhattan about social epidemics and their potential implications for the church.

How does thinking in terms of epidemics help us understand our social worlds?

It gives us a new appreciation for the extent to which ideas and behaviors can be contagious, and that we pick things up largely involuntarily. When your 6-year-old decides she wants a Cabbage Patch Doll, she's not sitting down and making a rational choice. She has caught the Cabbage Patch "virus." She caught it the same way kids catch a cold virus in first grade.There are moments when all of us get swept up in causes, ideas, and behaviors. There's this notion that every time we do something, it's because we sit down and make a rational choice. But we fool ourselves when we think that individuals are autonomous creatures. We're not. We are exquisitely sensitive to the pressures and influences ...