Extraordinary Popular Delusions and the Madness of Crowds

This book, first published in 1841, is an early study of crowd psychology by Charles Mackay.

It chronicles numerous instances of mass hysteria and popular delusions, including economic bubbles like the South Sea Bubble and Tulipomania, the Crusades, witch-hunts, and other peculiar follies.

Mackay presents these examples to illustrate how easily the masses can be led astray by various delusions and how human folly remains a constant across different times and places.

The book is divided into sections such as 'National Delusions,' 'Peculiar Follies,' and 'Philosophical Delusions,' and is known for its engaging and witty narrative style.