Black-Scholes works for short-term options, but if it's a long-term option and you think you know something [about the underlying asset], it's insane to use Black-Scholes.

'Crowd folly', the tendency of humans, under some circumstances, to resemble lemmings, explains much foolish thinking of brilliant men and much foolish behavior - like investment management practices of many foundations represented here today. It is sad that today each institutional investor apparently fears most of all that its investment practices will be different from practices of the rest of the crowd.

If the same family were always on the bottom, then you'd have big resentments. But if DuPonts go down and Pampered Chef up, [that's good]. That much churn makes people think the system is fairer. Buffett: We don't like churn now, but we liked it more 30-40 years ago.

If we mix only a moderate minority share of turds with the raisins each year, probably no one will recognize what will ultimately become a very large collection of turds.

It takes character to sit there with all that cash and do nothing. I didn't get to where I am by going after mediocre opportunities.

If (investing) weren't a little difficult, everybody would be rich.

Acquire worldly wisdom and adjust your behavior accordingly. If your new behavior gives you a little temporary unpopularity with your peer group then to hell with them.