The idea of excessive diversification is madness.

Well the open-outcry auction is just made to turn the brain into mush: you've got social proof, the other guy is bidding, you get reciprocation tendency, you get deprival super-reaction syndrome, the thing is going away... I mean it just absolutely is designed to manipulate people into idiotic behavior.

Investing is where you find a few great companies and then sit on your ass.

Where you have complexity, by nature you can have fraud and mistakes. You'll have more of that than in a company that shovels sand from a river and sells it. This will always be true of financial companies, including ones run by governments. If you want accurate numbers from financial companies, you're in the wrong world.

Obviously if you want to get good at something which is competitive, you have to think about it and practice a lot. You have to keep learning because world keeps changing and competitors keep learning. You have to go to bed wiser than you got up. As you try to master what you are trying to do – people who do that almost never fail utterly. Very few have ever failed with that approach. You may rise slowly, but you are sure to rise.

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.

I regard the amount of brainpower going into money management as a national scandal. When some idiot would get rich, they'd say, 'Well, old Charlie was out in the field playing the big brass tuba on the day it rained gold.' A lot of people have become rich lately who were playing the tuba on the day it rained gold.