Read HPMOR. Unlike what I thought it might be, the protagonist does not solve problems through pointing out logical fallacies or something. Harry Potter is a straight-up superhero who is infinitely smarter and more talented than anyone around him. It's not so much rationality as a narcissistic fantasy that goes on for hundreds (thousands?) of pages.

Even though I had been well-disposed to rationalism and read HPMOR to learn more, I could not take Yudkowsky seriously in any way after I gave up halfway through.

Had a similar experience trying to read that. You know you meet or have to work with people like that in your life and hopefully you use those experiences to remind yourself what kind of person you don't want to be.