Five Historical Manias That Gripped Societies, Then Disappeared

'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 slowly, and one by one.' Charles Mackay may have written those words in 1841 in his social science classic, Extraordinary Popular Delusions and the Madness of Crowds, but what he has to say about mass manias and the behavior of crowds remains absolutely relevant today - as anyone who's ever gone to a midnight sale of one of the Twilight books could tell you.

Mob mentality also goes some of the way - but not all the way - in explaining these real manias and outbreaks of strange behavior that came on disturbingly fast and disappeared just as rapidly.