"The best idea I've ever heard in psychology is this. People's behavior is driven primarily by two main, external forces. Driving forces and restraining forces. If you want to change people's behavior, there is a good and a bad way to do it. The good way is to diminish restraining forces, not by increasing driving forces. That turns out to be profoundly non-intuitive." -- Daniel Kahneman, psychologist and Nobel Laureate citing Kurt Lewin, a German-American psychologist who de