During the past two centuries, innovation has more than doubled our life span and given us cheap energy and more food. If we project what the world will be like 10 years from now without continuing innovation in health, energy or food, the picture is dark.

The barrier to change is not too little caring; it is too much complexity. To turn caring into action, we need to see a problem, see a solution, and see the impact. But complexity blocks all three steps.

When you write a piece of software you assume a certain type of hardware. If you assume hardware that's too powerful then you can't sell many copies cause very few people have that machine. If you assume hardware that's too simple your product can't do as much.

Depending on how quickly you get ocean rise, you have people who live in river deltas [at risk]. Bangladesh is largely a river delta, and the rising sea level means that when storms come in, the human sanitation is backing up, the ability to farm, it's destructive-type situations like you saw in New Orleans with Katrina. You're increasing the frequency of that stuff in low-lying areas fairly dramatically.

If you’re a person struggling to eat and stay healthy you might have heard about Michael Jordan or Muhammad Ali, but you’ll never have heard of Bill Gates.

If your goal is to make the world a better place, one thing you can do is pick a specific challenge that you really care about. Then, learn as much as you can about it and try to volunteer your time to help an organization that is working in this area. While you're doing that, look for creative new ways to use technology to tackle parts of the problem that you come in contact with.

The concept of this so-called "TerraPower reactor" is that you, in the same reactor, you both burn and breed. So, instead of making plutonium and then extracting it, we take uranium - the 99.3 percent that you normally don't do anything with - we convert that, and we burn it.