@sanau: Because they're not thinking. They're feeling. Emotions are often the nose-rings people get led around by.
@thedisasterautist I attended a private girls' school. There were 31 of us in my graduating class. One of my classmates is now a rabid anti-vaxxer (and one of the reasons I stayed away from our 40th reunion this year).
We had the same science classes. We were both taught how to think critically, but for her it clearly didn't take.
Thing is, she always had a rather loose association with truth; often deciding that reality was whatever she wanted it to be.
@thedisasterautist Yep. At one point, I tried pointing to vaccination maps that consistently showed wealthier communities (not just billionaires and politicians) with much higher vaccination rates - but some people just can't reason.