“Men, it has been well said, think in herds; it will be seen that they go mad in herds, while they only recover their senses one by one.”

Emphasising the difficulty of resisting collective error · Extraordinary Popular Delusions and the Madness of Crowds, preface

• Hope
• Truth

“The history of the world is but the history of the human mind, and the history of the human mind is but the history of its errors and its follies.”

The wording is commonly attributed to Mackay, but its exact textual source is difficult to verify. · Extraordinary Popular Delusions and the Madness of Crowds

• Memory
• Truth

“Every age has its peculiar folly—some scheme, project, or fantasy into which it plunges, spurred on either by the love of gain, the necessity of excitement, or the mere force of imitation.”

Observing how profit, excitement, and imitation drive mass behaviour · Extraordinary Popular Delusions and the Madness of Crowds, preface

• Fame
• Truth