Have you ever met an actual dumb person?

I was thinking about this. I went to university, and I worked in tech for decades. I met many assholes but I didn't meet anyone that would fit on the left half of the bell curve (less than 100 iq).

Since I've been living in that bubble my entire life, I'm curious of your stories. Have you met someone who was actually quite dumb (not just having opinions you don't agree with) and do you have an example situation you remember you can share?

Hopefully this becomes more funny than hateful since intelligence is not the value of a person, but it can be funny to read the stories.