Bubbles without markets
Robert J. Shiller reminds us that bubbles go beyond markets:
But, before we conclude that we should now, after the crisis, pursue policies to rein in the markets, we need to consider the alternative. In fact, speculative bubbles are just one example of social epidemics, which can be even worse in the absence of financial markets. In a speculative bubble, the contagion is amplified by people’s reaction to price movements, but social epidemics do not need markets or prices to get public attention and spread quickly.