Reality will always blindside those who turn their backs on it.
Joseph P. Overton created the Overton Window to describe the limits of politically acceptable discourse. Topics within the Window can be discussed, while subjects outside are suppressed. The Overton Window moves as society changes. It can be forced to move by opinion leaders. One example comes from Hans Christian Anderson’s story The Emperor’s New Clothes. The con men proclaim that only smart people can see the clothes. This puts the subject that the emperor is in fact naked outside the Overton Window. No one wants to mention it, lest he be thought stupid.
Crystallization is the phenomenon by which a group arrives at a common opinion and then enforces that opinion by punishing dissenters. Crystallization is very harmful to the progress of science. New hypotheses that cover new facts face resistance. The forming, breaking, and reforming of opinion about the Emperor’s New Clothes demonstrates this process.
A Preference Cascade occurs when people realize that an opinion they each held privately is in fact held by many other people. This can cause drastic changes in group behavior. Returning to the Emperor’s New Clothes, once the child states that the Emperor is naked, all the adults feel free to state the same thing. They start mocking the Emperor and the con men are forced to flee for their lives.
When the Overton Window not longer includes reality, in other words when reality can no longer be discussed, the stage is set for a preference cascade. Crystallization may make it harder to reference reality in a discussion. However, eventually reality will force itself into the public discussion. The resulting cascade can be very violent.