When it comes to fund managers and market strategists, this year's hero usually turns into next year's zero.

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.

Wall Street is littered with the bones of those who knew just what to do, but could not bring themselves to do it.

The key aspect of an index fund is that many of them, not all of them, but many of them are extremely cheap.

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.

When it comes to fund managers and market strategists, this year's hero usually turns into next year's 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).