Interview with Eugene Fama: Rational Irrationality : The New Yorker:
"It’s easy to say prices went down, it must have been a bubble, after the fact. I think most bubbles are twenty-twenty hindsight. Now after the fact you always find people who said before the fact that prices are too high. People are always saying that prices are too high. When they turn out to be right, we anoint them. When they turn out to be wrong, we ignore them. They are typically right and wrong about half the time."And another:
"The variance of stock returns for the market as a whole went up to, like, sixty per cent a year—the Vix measure of volatility was running at about sixty per cent. What that implies is not a credit market crisis. It would be stupid for anybody to give credit in those circumstances, because the probability that any borrower is going to be gone within a year is pretty high. In an efficient market, you would expect that debt would shorten up. Any new debt would be very short-term until that volatility went down."
Read more here.