Sometimes, I want to cause a person bodily harm.

Them: "The official story of 9-11 is full of holes. Take the --"

Me: "Please, stop, because seeing this happen to you is making me die inside.
Conspiracy theories represent a known glitch in human reasoning. The theories are of course occasionally true, but their truth is completely uncorrelated with the believer's certainty. For some reason, sometimes when people think they've uncovered a lie, they raise confirmation bias to an art form. They cut context away from facts and arguments and assemble them into reassuring litanies. And over and over I've argued helplessly with smart people consumed by theories they were sure were irrefutable, theories that in the end proved complete fictions. Those Moon Landing people, the 'Dumbledore's Still Alive' groupies, the Perpetual Motion subculture--can't you see you're falling into the same pattern?!"

Them: "Wait, you don't seriously believe we landed on the moon. Do you?"

Me: *Flees*