Alaska Must Be an Island
A girl in an AP US history class laughed at me when I was talking about driving to Alaska from Oregon. She insisted that Alaska was an island because of how it is separated out on maps from the rest of the USA.
I don’t know if she was necessarily the dumbest person I’ve met overall, but it was certainly the dumbest thing I ever saw someone insist that they were right about.
Story credit: Reddit / Cyrano_de_Boozerack