The optimum human population of earth is zero.

I founded Friends of the Earth to make the Sierra Club look reasonable. Then I founded the Earth Island Institute to make Friends of the Earth seem reasonable.

Free shackled rivers!...The finest fantasy of eco-warriors in the West is the destruction of [Glen Canyon] Dam and the liberation of the Colorado [River].

I believe that human overpopulation is the fundamental problem on Earth Today" and, "We humans have become a disease, the Humanpox

The optimum human population of earth is zero.

Capitalism is a cancer in the biosphere.

Phasing out the human race will solve every problem on earth, social and environmental.