Managing director and chief investment officer, Vanguard
I got my number-one piece of financial advice in an investments course at the University of Chicago business school in 1979. It may sound a little self-serving: Index investing is a great way to gain exposure to the marketplace.
The second-best advice I ever received came from a friend of my parents. He said, if you think investments are going to do something within a certain time frame, double that time frame. It could be anything from growth stocks outperforming value stocks to the dollar strengthening. That kind of advice gives you a dose of humility: It acknowledges that trying to exploit a trend is very difficult, even if you're right about it, because your timing may be all off.
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