Michael Lewis on why fatherhood makes him risk averse – even averse to the stock market, which he covers.

A few years ago a piece in the University of Michigan medical journal argued that the reason the internet bubble reached such ridiculous heights was that huge numbers of investors were now taking drugs that lowered their inhibitions. With a third of the U.S. investing population on Prozac or some other mood-enhancing drug, the paper concluded, it was no wonder that so many people believed the market would simply keep rising.