No government is here forever. And there are other forces - the most potent force in our society, in fact, big business - doing good for the environment.

History as well as life itself is complicated -- neither life nor history is an enterprise for those who seek simplicity and consistency.

Forced to choose between limiting population or trying to increase food production, we chose the latter and ended up with starvation, warfare, and tyranny.

The adoption of agriculture, supposedly our most decisive step toward a better life, was in many ways a catastrophe from which we have never recovered.

AIDS and malaria and TB are national security issues. A worldwide program to get a start on dealing with these issues would cost about $25 billion... It's, what, a few months in Iraq.

We're uncomfortable about considering history as a science. It's classified as a social science, which is considered not quite scientific.

Biology is the science. Evolution is the concept that makes biology unique.

Technology has to be invented or adopted.

Rhino-mounted Bantu shock troops could have overthrown the Roman Empire. It never happened.

Human societies vary in lots of independent factors affecting their openness to innovation.

Why did human development proceed at such different rates on different continents for the last 13,000 years?

Sometimes I think we can tell how important it is to risk by how dangerous it is to do so.

You don't change your style by changing your bag. You change it with your clothes.

If you're doing something, if you're following something that is directly at odds with who you are, you've got to slow down and ask yourself why you're following that dream.

As president, I could run the Trump organization, great, great company, and I could run the company - the country. I'd do a very good job, but I don't want to do that.

The secret is to just keep moving.

The sea is whipping the skyThe sky is whipping the seaYou can hide away forever from the stormBut you'll never hide away from me.

Peace equals ability to handle conflict, with empathy, nonviolence, and creativity.

People go tanning because they like to feel tan. You feel more sexy when you're tan and I don't understand why you would tax on that, because you're making yourself feel more happy about yourself.

Small developers can compete on creativity not on scale or staff size.... Nintendo is willing to help bring these ideas to life.