I used to believe the moon landing was faked, then I compared the math to a high school physics problem
For years I was the guy at parties saying the moon landing was shot in a studio, mostly because I saw a YouTube video in 2014 that pointed out the flags looked weird. Then my nephew asked me to help with his physics homework about thrust and gravity, and we worked through the Saturn V numbers on a napkin at his kitchen table in Fresno. I realized the fuel-to-payload ratio actually matched what NASA published, and my "common sense" gut check was just me not understanding basic rocketry. Now I ask people to show me the actual numbers when they bring up the studio theory, and most of the time they just send me another clip. Has anyone else had a topic where doing the boring math changed your mind more than any debate did?