So, some scientists have developed a new test, hopefully more definitive, to determine whether or not a person is sane.
For part of it, the tested person watches film clips, and is asked to say what happens next.
For example, they can watch a man and a woman walk down the street together, and the woman is obviously either about to break up with the man, or is about to tell him she is pregnant, or whatever. The film stops and the insane person is asked "What were those two people going to do next?"
He answers "Break for lunch."