The single most important problem is our misguided focus on identifying the single most important problem!

One way to explain the complexity and unpredictability of historical systems, despite their ultimate determinacy, is to note that long chains of causation may separate final effects from ultimate causes lying outside the domain of that field of science.

All human societies go through fads in which they temporarily either adopt practices of little use or else abandon practices of considerable use.

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

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

I'd rather spend my leisure time doing what some people call my work and I call my fun.

But this was the only way of life that humans knew for their first 6m years on the planet. In giving it up over the past few thousand years, we have lost our vulnerability to disease and cold and wild animals, but we have also lost good ways to bring up children, look after old people, stave off diabetes and heart disease and understand the real dangers of everyday life.