I believe that accurate knowledge is very, very important, but find that out in free time. Don't let it take over every hour of the day. Perhaps most important, talk about it.

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.

My mother always taught us that if people don't agree with you, the important thing is to listen to them. But if you've listened to them carefully and you still think that you're right, then you must have the courage of your convictions.

One individual cannot possible make a difference, alone. It is individual efforts, collectively, that makes a noticeable difference - all the difference in the world!

I cannot remember a time when I did not want to go to Africa to study animals.

We can't leave people in abject poverty, so we need to raise the standard of living for 80% of the world's people, while bringing it down considerably for the 20% who are destroying our natural resources.

If you look into their [chimpanzees] eyes, you know you're looking into a thinking mind. They teach us that we are not the only beings with personalities, minds capable of rational thought, altruism and a sense of humor. That leads to new respect for other animals, respect for the environment and respect for all life.