The human population can no longer be allowed to grow in the same old uncontrollable way. If we do not take charge of our population size, then nature will do it for us and it is the poor people of the world who will suffer most

All we can hope for is that the thing is going to slowly and imperceptibly shift. All I can say is that 50 years ago there were no such thing as environmental policies.

We really need to kick the carbon habit and stop making our energy from burning things. Climate change is also really important. You can wreck one rainforest then move, drain one area of resources and move onto another, but climate change is global.

There is no question that climate change is happening; the only arguable point is what part humans are playing in it.

If my grandchildren were to look at me and say, 'You were aware species were disappearing and you did nothing, you said nothing', that I think is culpable. I don't know how much more they expect me to be doing, I'd better ask them.

The question is, are we happy to suppose that our grandchildren may never be able to see an elephant except in a picture book?

You'll find people where their conditions aren't changing in any way, its rather rare for them to be happy.