Climate scientists think of nothing but climate and then express their concerns in terms of constructs such as global mean surface temperature. But we live in a world in which all sorts of change is happening all the time, and the only way to understand what climate change will bring is to tell stories about how it manifests in people's lives.

Most of what we think of as distinctively human has occurred in the last 10,000 years in the Holocene - a period in which the Earth was abnormally quiet.

One of the real dangers of our time is people's indifference to history.

Our differences should not be exaggerated.

Moral revolutions are typically seen retrospectively. Prospectively, the revolutionaries tend to look like crazy people, and sometimes they are.

Increasingly both environmentalists and animal ethicists recognize the enormous destruction caused by animal agriculture.

It's obvious that there are vast variety of consequentialist views, depending on what we think goodness consists in, what our notion of consequence is, and what level (or levels) of human action we think the principle should be applied.