But why are there some areas-- like politics and religion-- where irrationality seems especially pronounced? My answer is that irrationality, like ignorance, is sensitive to price, and false beliefs about politics and religion are cheap. If you underestimate the costs of excessive drinking, you can ruin your life. In contrast, if you underestimate the benefits of immigration, or the evidence in favor of the theory of evolution, what happens to you? In all probability, the same thing that would have happened to you if you knew the whole truth.

In a sense, then, there is a method to the average voter's madness. Even when his views are completely wrong, he gets the psychological benefit of emotionally appealing political beliefs at a bargain price. No wonder he buys in bulk.