Actor and comedy legend John Cleese joined theCUBE hosts Dave Vellante and John Furrier at Knowledge 15 in Las Vegas to talk about geeks, conventions, and everything wrong with the world.

“I like geeks because they all like Monty Python,” Cleese joked. He explained that most of the speeches he gives are to people in the software industry, so he has a lot of geek jokes. “They all like Python because they’re extremely smart, and as you know, people who like Python are astonishingly smart.”

While the hosts asked a few questions from people on social media, a user on Facebook asked Cleese what he thought of “the double curse of incompetence,” also called the Dunning-Kruger effect. Cleese said that David Dunning, a Cornell professor for whom the effect is partially named, is “one of the most amusing and entertaining guys I’ve ever met.”

“In order to know how good you are at something requires almost exactly the abilities that it does to be good at that thing in the first place,” Cleese said, explaining the idea behind the self assessment and the Dunning-Kruger effect. “So if you’re absolutely no good at something, you lack exactly the abilities that you need to know that you’re no f—ing good at it. And that explains the planet better than anything else I’ve ever come across.”

He added, “There’s a whole lot of people out there who have no idea what they’re doing, but they have absolutely no idea that they have no idea what they’re doing. And those are the ones with the confidence and stupidity who finish up in power. That’s why the planet doesn’t work.”

Watch the full interview with Cleese here, along with an unexpected ending.