Now, we put out a lot of carbon dioxide every year, over 26 billion tons. For each American, it's about 20 tons. For people in poor countries, it's less than one ton. It's an average of about five tons for everyone on the planet. And, somehow, we have to make changes that will bring that down to zero.

We have completely eradicated smallpox; we have almost eradicated polio. That's the miracle of vaccines, which is even greater than that of antibiotics.

[AIDS ] is not a short-term emergency but it is something that, just like smallpox was many decades ago, we should aim for complete eradication.

If you really could take the CO2, when you burn hydrocarbons - coal, for example - if you could really capture the carbon and sequester it - they call it CCS - if the extra capital cost, energy cost, and storage costs over time didn't make it super expensive, then that's another path that you could go down.

There are websites that any government wants to block. The truth about the Internet is that it's extremely hard to block anything - extremely hard. You'll never get perfect blocking.

Software is the magic thing whose importance only goes up over time.

Software is a great combination between artistry and engineering. When you finally get done and get to appreciate what you have done it is like a part of yourself that you've put together. I think a lot of the people here feel that way.