Be neither too remote nor too familiar.

There's nothing like a jolly good disaster to get people to start doing something.

Business is recognizing the role it can play in combatting climate change. Thank God, is all I can say, for there is a desperately urgent need for business to play that role. Your lobbying influence can be substantial, but together, united and in large enough numbers it could prove decisive in turning the tide.

If you chuck away too many things, you end up discovering there was value in them.

The world's forests need to be seen for what they are - giant global utilities, providing essential public services to humanity on a vast scale. They store carbon, which is lost to the atmosphere when they burn, increasing global warming. The life they support cleans the atmosphere of pollutants and feeds it with moisture. They act as a natural thermostat, helping to regulate our climate and sustain the lives of 1.4 billion of the poorest people on this Earth.

If you think about the impact of climate change, [it should be how] a doctor would deal with the problem. A scientific hypothesis is tested to absolute destruction, but medicine can't wait. If a doctor sees a child with a fever, he can't wait for [endless] tests. He has to act on what is there. The risk of delay is so enormous that we can't wait until we are absolutely sure the patient is dying.

If you think about your and my grandchildren, this is what really worries me. I don't want them - if I'm still alive by then - to say, 'Why didn't you do something about it?', when you could have done.