Each evening, I ached for the shelter of my tent, for the smallest sense that something was shielding me from the entire rest of the world, keeping me safe not from danger, but from vastness itself. I loved the dim, clammy dark of my tent, the cozy familiarity of the way I arranged my few belongings all around me each night.

And there are my cats, engaged in a ritual that goes back thousands of years, tranquilly licking themselves after the meal. Practical animals, they prefer to have others provide the food ... some of them do. There must have been a split between the cats who accepted domestication and those who did not.

I became an environmentalist because I love the living world, but I spend much of my life thinking about electricity, industrial processes and civil engineering.

Nature! We live in her midst and know her not. She is incessantly speaking to us, but betrays not her secret. We constantly act upon her, and yet have no power over her. Variant: NATURE! We are surrounded and embraced by her: powerless to separate ourselves from her, and powerless to penetrate beyond her.

A large animal needs a large area. If you protect that area, you're also protecting thousands of other plants and animals. You're saving all these species that future generations will want - you're saving the world for your children and your children's children. . . . The destruction of species is final. If you lose a species, you lose the genes, you lose all the potential drugs and potential foods that could be useful to the next generations. The ecosystems will not function as they have.

The ecological crisis shows the urgency of a solidarity which embraces time and space... A greater sense of intergenerational solidarity is urgently needed. Future generations cannot be saddled with the cost of our use of common environmental resources.