This is dogmatism, or "speaking in absolutes", and it's extremely common with pseudo-intellectuals in general. The Dunning-Kruger effect also applies to smart

This is dogmatism, or "speaking in absolutes", and it's extremely common with pseudo-intellectuals in general. The Dunning-Kruger effect also applies to smart people. You don't stop when you are estimating your ability correctly. As you learn more, you gain more awareness of your ignorance and continue being conservative with your self estimates. My own take on this: I think real intelligence by definition requires humility. One has to realize that we can't know the things we don't know, which includes the fact that we can't always trust our own beliefs and opinions because we might be relying on faulty or incomplete information, or we might be suffering from a mental health problem, whether we are aware of it or not. "As a rule, strong feelings about issues do not emerge from deep understanding." -Sloman and Fernbach