It can change their behavior.
I know it works because I have tried it.
(I won’t tell you on who.)
Like everything else though, you have to ask it in the right situation.
Wait for someone who wants to be like X, do the opposite of X.
And then call them out for it.
You can literally see cognitive dissonance flash across their face.
Let Adam’s explain:
The next time someone is doing something you find objectionable, don’t attack that person’s actions. Instead, ask if this is who the person wants to be. Most people think they are good people, even if they sometimes do bad things. If you remind them of their identity, and their aspirations for their identity, you will usually be met with cognitive dissonance and an implied promise to change. That might look like this: Other person: “I like defacing the political signs on the other side. Ha-ha! It’s hilarious.” You: “Is that the person you want to be?” Other person (now with cognitive dissonance): “Um, I was just doing it that one time because I was with Bob, and we had some drinks.” Obviously this method won’t work with kids, or with adults who have cultivated a brand around doing all the wrong things. But if you catch a normal adult doing something outside what you imagine is their aspiration of a core identity, you can sometimes flip them to be compatible with their preferred identity almost instantly. Just point out the gap and watch it close.