I've also heard it posed that we're actually all the same person being reborn into every human that has ever or will ever exist, without regard for chronology. So like the people who are most cruel are our earliest selves and the people who are more empathetic are later versions of us who have learned to be more compassionate.

I don't believe that, but I like to think about it because it makes me more thoughtful of others.

Also, some people believe the Earth is flat.