Charles Mackay 
Extraordinary Popular Delusions and the Madness of Crowds 
Understanding the Forces Behind Group Mentality, Thoughts and Actions

This edition represents an early study of crowd psychology by Scottish journalist Charles Mackay. The book chronicles its subjects in three parts: ‘National Delusions’, ‘Peculiar Follies’, and ‘Philosophical Delusions’. Mac Kay was an accomplished teller of stories, though he wrote in a journalistic and somewhat sensational style. The subjects of Mackay’s debunking include alchemy, crusades, duels, economic bubbles, fortune-telling, haunted houses, the Drummer of Tedworth, the influence of politics and religion on the shapes of beards and hair, magnetisers (influence of imagination in curing disease), murder through poisoning, prophecies, popular admiration of great thieves, popular follies of great cities, and relics. Present-day writers on economics, such as Michael Lewis and Andrew Tobias, laud the three chapters on economic bubbles. Scientist and astronomer Carl Sagan mentioned the book in his own discussion about pseudoscience, popular delusions, and hoaxes.
Charles Mackay was a Scottish poet, journalist, author, anthologist, novelist, and songwriter.