I've met someone who claimed he believed in the flat earth theory. I see no reason to believe he was misleading me. Not massively educated, not really intereste

I've met someone who claimed he believed in the flat earth theory. I see no reason to believe he was misleading me. Not massively educated, not really interested in analytical games. I've met people who believed they could communicate with aliens by meditating under pyramids made of steal pipes. I've met people who believed that putting a crystal on a bottle of water will make it stay fresh longer. That they could charge batteries with their mind. Not sure what kind of proof you might want to be sure these people really believe what they say. And I'm not sure how meaningful that statement is. I never thought they were playing the mind of fan-fic games you suggest though. My observations lead me to believe people in general believe some pretty weird things.