When does a gag go too far?

April 1st has become an unofficial day of celebration for pranksters -- and of dread for the paranoid. Practical jokes, horseplay and other high jinks abound on April Fools Day -- but the shenanigans often come at someone's expense. 

For insight on when a joke isn't funny and a gag goes too far, Jian speaks with The Humour Code co-authors Peter McGraw, director of the University of Colorado Humor Lab, and Joel Warner. 

Find the sweet spot

"There's a long history to humour's dark side. Plato and Aristotle actually viewed humour as a negative thing and only very recently have people started to think about it with regard to its benefits," says McGraw. 

"You have to find the sweet spot between having enough of a violation and finding enough of a way to make this ok. So think about what is the worst case scenario; if this goes horribly wrong, if this is taken out of context, how are you going to look?"