If something's expensive to develop, and somebody's not going to get paid, it won't get developed. So you decide: Do you want software to be written, or not?

Philanthropy, although it's tiny compared to the government, it's 2% of the US economy, which is the largest percentage, other than the Middle East.

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

Understanding science and pushing the boundaries of science is what makes me immensely satisfied.

The obvious mathematical breakthrough would be development of an easy way to factor large prime numbers.

Today, we take the risk of nuclear war quite seriously, climate change not so much and epidemics least of all. But no single country, not even the United States, is well prepared. And even if one country is doing the right things to protect itself, it has to be a global thing.

I'm a great believer that any tool that enhances communication has profound effects in terms of how people can learn from each other, and how they can achieve the kind of freedoms that they're interested in.