This is going to be hard to believe, but something that really helped me understand the diversity of what being "right" means is listening to old episodes of This American Life.

There are lots of stories about a normal person in an unusual situation who ends up behaving "strangely" or making decisions it's hard to understand, or there are stories about people in very normal situations who are just very unusual people.

Either way, you learn that everything is a shade of gray and certainty is the most likely way that someone can be wrong.