Charles Mackay's Extraordinary Popular Delusions and the Madness of Crowds is a timeless study of human folly, mass psychology, and the irresistible power of collective obsession. First published in 1841, the book explores how entire societies can fall under the sway of irrational beliefs, speculative frenzies, and dangerous superstitions. Mackay vividly recounts some of history's most famous manias, including the Dutch Tulip Bubble, the South Sea Company scandal, and the Mississippi Scheme. He also examines witch hunts, alchemy, fortune-telling, and other cultural crazes that reveal the ease with which reason can be abandoned in favor of fear, greed, or blind faith. Written with wit, clarity, and moral insight, Mackay's work is more than a catalog of historical curiosities. It is a warning against the dangers of groupthink and the cyclical nature of mass hysteria, showing how easily people can be swept up in movements that defy logic. Generations of readers—from historians and economists to psychologists and investors—have returned to this book for its engaging stories and enduring lessons about human behavior. Extraordinary Popular Delusions and the Madness of Crowds remains a classic, as relevant today as in the nineteenth century, reminding us that the madness of crowds is never far from the surface of society.