No one in his right mind would walk into the cockpit of an airplane and try to fly it, or into an operating theater and open a belly. And yet they think nothing of managing their retirement assets. I've done all three, and I'm here to tell you that managing money is, in its most critical elements even more demanding than the first two.

The key thing about any fund is to make sure its expenses are low. You know, if you look at the funds in your plan and you see that they're all charging 1.5 and 2 percent,you've gota bad plan.

Mutual fund manager performance does not persist and the return of stock picking is zero.

It's human nature to find patterns where there are none and to find skill where luck is a more likely explanation (particularly if you're the lucky manager).

Do the math. Expect catastrophes. Whatever happens, stay the course.

You have to understand your own psychology. You have to understand that human beings weren't really designed to invest. We have all these emotions that are appropriate responses if you're being chased by a tiger, but they're terrible responses if you've got a 30-year time horizon to think about investment or when you're trying to manage investment over 30 years.

Investment success accrues not so much to the brilliant as to the disciplined.