Put another way, the chimpanzees' closest relative is not the gorilla but humans.

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?

I think that most of us instinctively avoid people with mental illness.

Much of my high-jinx have been drug-related. When you're under 30, whatever, but once you're past 40 it's just ugly.

To this noble end the delegates had pledged their lives, their fortunes, and their sacred honor.

A good man not only forbears those gratifications which are forbidden by reason and religion, but even restrains himself in unforbidden instances.

One knows one's madnesses, by and large. By and large the knowledge is vacuous. The notion of naming the beast to conquer it is the idiot optimism of psychotherapy.

The hand is the visible part of the brain.

You ain't ever gonna get an Academy Award for doing 'Crank,' and you certainly won't for doing all the other movies I've done.

Human civilization is not something achieved against nature; it is rather the outcome of the working of the innate qualities of man.

Eventually, I decided that thinking was not getting me very far and it was time to try building.

Follow your passion. Magic has no formula.