Freakonomics Lesson Plan

How does conventional wisdom come about? What are some motivating factors, or incentives, for the creation of conventional wisdom?

Experts often have a hand in creating conventional wisdom. In order to get the attention of the media, experts will often exaggerate or even fabricate data. And the media needs experts as badly as experts need the media: newspapers and TV newscasts need stories, and an expert with a sensational piece of wisdom is always welcome. Advertising, too, is a brilliant tool for creating conventional wisdom.

Advocates for causes can also indulge in some creative lying. They do so to attract the money and political capital necessary to address the...