I met a lady once that was thinking about Science, and she pointed out to me that the World should've run out of Oxygen by now. I asked her if she was talking about Climate change but she said 'no, we're breathing the same air that cavemen did, shouldn't we have run out of Oxygen by now?'
I didn't know if she was joking or not, in case she wasn't I explained how Trees worked to her.

I'm never surprised by someone believing in a flat earth, just sad. So so sad.