"Wizard's First Rule: people are stupid." Richard and Kahlan frowned even more. "People are stupid; given proper motivation, almost anyone will believe almost anything. Because people are stupid, they will believe a lie because they want to believe it's true, or because they are afraid it might be true. People's heads are full of knowledge, facts, and beliefs, and most of it is false, yet they think it all true. People are stupid; they can only rarely tell the difference between a lie and the truth, and yet they are confident they can, and so are all the easier to fool.
"Because of Wizards First Rule, the old wizards created Confessors, and Seekers, as a means of helping find the truth, when the truth is important enough. Darken Rahl knows the Wizard's Rules. He is using the first one. People need an enemy to feel a sense of purpose. It's easy to lead people when they have a sense of purpose. Sense of purpose is more important by far than the truth. In fact, truth has no bearing in this. Darken Rahl is providing them with an enemy, other than himself, a sense of purpose. People are stupid; they want to believe, so they do."
Wizards are wrong and their own data proves it. If a person will believe anything because of motivation, it's not stupidity that causes belief but motivation. But the real motivations people have are unconscious. So again believing something because you are unconsciously motivated to and have no idea that you are is not stupid but acting our unconscious behavior. Furthermore, the more intelligent a person is the better able they are to do this, and even furthermore than that is the fact that this can't be cured by intellect but only by feeling. You can never think your way to what you feel, you can only feel it and it is exactly the fear of feeling our unconscious motivations that cause them to exist.