In contexts of uncertainty, herding is what Prechter terms “pre-rational.” It is not governed by the same part of the brain and the same mental processes as solving a math problem or rational herding in contexts of certainty—queuing up early with your friends for what you all know will be a sold out concert. Pre-rational herding impulses take precedence over rational reflexion and are the fundamental psychological driver of inherently uncertain financial markets. So-called rational reflexion comes into play after the impulsive imperative, and is nothing more than rationalization for impulsive action or inaction performed either before or after the rationalization. Following the herd in financial markets brings participants to grief, because the herd always has and always will buy high and sell low.

This is an excerpt of Robert Gore's review of Robert Prechter's Socionomic Theory of Finance. For the full review, please click the above link.