elections in 20 social scientists demonstrated that large groups sharing similar ideas on social media may operate like echo chambers amplifying and strengthening beliefs in misinformation. Popular delusions began so early, spread so widely, and have lasted so. 'Financier Bernard Baruch credited the lessons he learned from Extraordinary Popular Delusions with his decision to sell all his stock ahead of the crash of 1929' (Wikipedia article on Extraordinary Popular Delusions, accessed 12-09-08).īetween the U.S. The memoirs of the South - Sea madness and the Missis- sippi delusion are more. 'Other bubbles described by Mackay are the South Sea Company bubble of 1711–1720, and the Mississippi Company bubble of 1719–1720. Allegedly, some tulip bulb varieties briefly became the most expensive objects in the world, 1637. According to Mackay, during this bubble, speculators from all walks of life bought and sold tulip bulbs and even futures contracts on them. 'Among the alleged bubbles or financial manias described by Mackay is the Dutch tulip mania of the early seventeenth century. The sub-headings of the three volumes were 'National Delusions', 'Peculiar Follies', and 'Philosophical Delusions.' It also contained early discussions of topics which were much later studied by sentiment analysis. The three volume work published in London on what later came to be called 'investor psychology' contained, among many other things, notable descriptions of financial bubbles. In 1841 Scottish poet, journalist, and song writer Charles Mackay issued Memoirs of Extraordinary Popular Delusions and the Madness of Crowds.

Memoirs of popular delusions