Have you ever watched a dog interact with its owner? The dog repeatedly looks at the owner, taking cues constantly. The owner is the leader, and the dog is a pack animal alert for every cue of what the owner wants it to do. Participants in the stock market are doing something similar. They constantly watch their fellows, alert for every clue of what they will do next. The difference is that there is no leader. The crowd is the perceived leader, but it comprises nothing but followers. When there is no leader to set the course, the herd cues only off itself, making the mood of the herd the only factor directing its actions.