Wide diversification is only required when investors do not understand what they are doing.

If you expect to be a net saver during the next 5 years, should you hope for a higher or lower stock market during that period? Many investors get this one wrong. Even though they are going to be net buyers of stocks for many years to come, they are elated when stock prices rise and depressed when they fall. This reaction makes no sense. Only those who will be sellers of equities in the near future should be happy at seeing stocks rise. Prospective purchasers should much prefer sinking prices.

The ability to say no is a tremendous advantage for an investor.

I always say that in investing you want to buy stock in a company that has a business that's so good that an idiot can run it, because sooner or later one will. We have a country like that.

Cash never makes us happy, but it's better to have the money burning a hole in Berkshire's pocket than resting comfortably in someone else's.

I read annual reports of the company I'm looking at and I read the annual reports of the competitors - that is the main source of material.

I'm sitting with six and a half billion dollars we're going to use to close the Mars-Wrigley deal on October 6. I've got to hand over that six and a half billion on October 6. Now, I have to be very careful about who I leave it in between now and then, because they're expecting that he show up.