In parts of Montana, salt concentrations in soil water, have reached those double those of seawater.

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?

Declarations of love amuse me. Especially when unrequited.

I didn't just see a child in my dreams—I felt it in my heart.

Conclusions that philosophers first establish by way of torturous reasoning have a way, over time, of leaking into shared knowledge.

He who fears he shall suffer already suffers what he fears.

Appearances are a glimpse of the unseen.

Say goodbye to the oldies, but goodies, because the good old days weren't always good and tomorrow ain't as bad as it seems

He who knows himself knows god.

I tend to be a bit of a workaholic, but I also can't function without some sort of domesticity as well.

The invasion of illegal aliens is threatening the health of many Americans.

There is a difference between a job and the promise of jobs, there is a difference between economic development and the promise of economic development.