Stupidity is a mystery. No one has ever observed it or heard it or felt it. We can see and hear and feel only what stupidity does. We know it makes people say strange things, make poor decisions, and ignore obvious facts. But we cannot say what stupidity is like.

We cannot even say where stupidity comes from. Some say it might stem from ignorance or misinformation. Others think that social influences or emotional bias produce some of it. All everyone knows is that stupidity seems to be everywhere and that there are many ways for it to surface.