Only through focus can you do world-class things, no matter how capable you are.

I went public too soon. Stay private as long as you can.

I'm an investor in a number of biotech companies, partly because of my incredible enthusiasm for the great innovations they will bring.

In most of these things our foundation is a co-funder, so I can say that a polio or an HIV vaccine, that I'm putting our resources behind it in a very big way and the U.S. government would be the best partner for those efforts.

In the US in the 1900's 60 % of people were employed on the farms. Today it's less than 1%. If you told people back then that this would happen they wouldn't have believed it. If you told them we would have therapy, massages and spas that played important parts in our lives they would've have believed us.

The next time someone tells you we can trim the budget by cutting aid, I hope you will ask whether it will come at the cost of more people dying.

I can understand wanting to have millions of dollars; there's a certain freedom, meaningful freedom, that comes with that.