The United States has long thought of itself as the land of infinite plenty, and historically we did have abundant resources. But now we are gradually exhausting our fisheries, our topsoil, our water. On top of that, we're coming to the end of world resources.

Introspection and preserved writings give us far more insight into the ways of past humans than we have into the ways of past dinosaurs. For that reason, I'm optimistic that we can eventually arrive at convincing explanations for these broadest patterns of human history.

Native Americans had only stone and wooden weapons and no animals that could be ridden. Those military advantages repeatedly enabled troops of a few dozen mounted Spaniards to defeat Indian armies numbering in the thousands.

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

I've always been a strong supporter of environmental protection and initiatives in that area. But I'm willing to set priorities. If we have to make reductions in one place, we'll have to-in order to increase another place, I'm willing to do that.

I don't own designer clothes, or a sports car, or a huge house, but I am seeing the world, experiencing amazing things, and I have become an environmental campaigner.

What is the future going to say about us now? What are our kids going to look at us and say, 'How could you not stop that person from getting into power? How could you not stop that environmental disaster that you saw coming a mile away?'

The paradigm of the 'Aquarian Conspiracy' sees humankind embedded in nature. It promotes the autonomous individual in a decentralized society... The new perspective respects the ecology of everything: birth, death, learning, health, family, work, science, spirituality, the arts, the community, relationships, politics.