What important truth do very few people agree with you on?

Originally asked

Peter Thiel, to job candidates, Zero to One, chapter 1, 2014

Peter Thiel, Zero to One, chapter 1, where it is introduced as his job-interview question. Thiel supplies his own standard: a good answer takes the form "most people believe x, but the truth is the opposite of x."

You answer as yourself. Nobody on FLAPSS answers as anybody else.