It's easy to become hopeless. So people must have hope: the human brain, the resilience of nature, the energy of young people and the sort of inspiration that you see from so many hundreds of people who tackle tasks that are impossible and never give up and succeed.

We have a responsibility toward the other life-forms of our planet whose continued existence is threatened by the thoughtless behavior of our own human species. . . . Environmental responsibility – for if there is no God, then, obviously, it is up to us to put things right.

You're thinking about putting scientists into small cages and doing research on them. I wish it could happen sometimes.

Farm animals feel pleasure and sadness, excitement and resentment, depression, fear, and pain. They are far more aware and intelligent than we ever imagined...they are individuals in their own right.

Every individual matters and has a role to play in this life on Earth.

I don't care two hoots about civilization. I want to wander in the wild.

Especially now when views are becoming more polarized, we must work to understand each other across political, religious and national boundaries.