That is "having to believe." It is usually related to income, but only because most people cannot imagine how they would eat without money, so income = food to their inner lizard.
They honestly believe they look at all the "facts" but they eliminate any and all sources that may present evidence to the contrary. Imagine, for instance, a doctor makes all of his money selling Wonderdrug. Wonderdrug makes most of his patients get better, but every time a blue eyed patient takes wonder drug they come in and tell him they hate it, it makes them sick. The doctor MAY consider that maybe blue eyed people are somehow to blame, they do not metabolize Wonderdrug correctly, perhaps.
Well, all of the doctors patients get together for a Town picnic, and they start talking about Wonderdrug and it turns out that many brown and green eyed people have problems, too. A few mentioned it, but the doctor did not seem too worried so they are not either. They all like the doctor so much... some just don't take it, or live with the side effects, or honestly believe the side effects are a NEW disease that they need Magicdrug to treat, so they are sent to the specialist for that.
The blue eye theory of the doctor is based on his choice to look for an external cause, he KNOWS Wonderdrug is not the problem. The first two or three people to complain all just happened to have blue eyes, and now when anyone complains he does not even look, he assumes they have blue eyes. One day, a group of his patients come to him and say "We want you to stop presciribing Wonderdrug, it is making people sick." How would doctor react to that news?
Oversimplified, but I think you can get my point, if you want to. Then again, you may just need Amazadrug... ;)
Most folks HAVE to believe their government is good, because the government is now our only "safety net."
And then of course there are trolls.
This is the article that got my posting privileges revoked: