A good parallel is how fad diets slip into the zeitgeist. People were already looking for a magic cure for their weight problems. When that cure falls on their

A good parallel is how fad diets slip into the zeitgeist. People were already looking for a magic cure for their weight problems. When that cure falls on their lap many people fall end up with a new (frequently self-destructive) solution. The key is the finding susceptible people and giving them the solution they were already looking for and it'll almost feel obvious.