The mentally disturbed do not employ the Principle of Scientific Parsimony: the most simple theory to explain a given set of facts. They shoot for the baroque.

When psychologically unfit form the majority in any sect, and yet proclaim to be the only fittest, will not only be a threat to the existence of the sane minority, but are surely catastrophic for the human race as a whole!

Every time you feel like mocking a person you disagree with politically by implying that they are mentally ill, I want you to instead imagine you are talking to every single person who actually is mentally ill and telling them they are worthless. That's how it makes mentally ill people feel. Doesn't seem very progressive now does it?