There are three people you shouldn’t yell at when they’re doing their jobs: A pilot, a ballerina, and Louis C.K. 

Well, maybe four—four people you shouldn’t yell at while they’re doing their jobs: A pilot, a ballerina, Louis C.K., and someone using a welding torch. (If the industrial films of yesteryear have taught us anything, you need to squeeze that last person’s shoulder.) Yes, these are four people who can’t perform to their full potential if you’re yelling at them, though only Louis C.K. is likely to dish out the verbal lashing seen in the video below. The person with the welding torch might blind you with white-hot light, but Louie will mark you for eternity (or however long it takes for this video to be the subject of a take-down notice) as an asshole who feels the need to shout their every thought at a person just doing what he does for money and to benefit his daughters’ school. That’s better than living with the guilt of causing someone to cut off his or her fingers with a band saw, we suppose. (And that makes five—five people you shouldn’t yell at while they’re working: A pilot, a ballerina, Louis C.K., a welder, and some sort of carpenter.) [h/t Grantland]