That's a central part of philosophy, of ethics. What do I owe to strangers? What do I owe to my family? What is it to live a good life? Those are questions which we face as individuals.

Sometimes we know the best thing to do, but fail to do it. New year's resolutions are often like that. We make resolutions because we know it would be better for us to lose weight, or get fit, or spend more time with our children. The problem is that a resolution is generally easier to break than it is to keep.

When diamonds' role in fuelling violent conflict in Africa gained worldwide attention, the diamond industry established the Kimberley process in order to keep ""blood diamonds"" out of international trade.

I'm not overly alarmist about it, but I do think there are some worrying signs, like the growing accumulation of wealth by a very small proportion of the population, plus elections in the US are much more dominated by money than anywhere else calling itself a democracy.

Building a 'Green Gabon' has always been a central pillar of my government, and in 2014, I introduced a new legal framework that puts environmental protection and sustainable development firmly at the heart of our future economic growth.

When sustainability is viewed as being a matter of survival for your business, I believe you can create massive change.

We will need to reach out to all those actors - to governments, to civil societies, to businesses - and help in mobilizing them to help in this fight against climate change.

One volcano puts out more toxic gases - one volcano - than man makes in a whole year. And when you look at this 'climate change,' and when you look at the regular climate change that we all have in the world, we have warm and we have cooling spells.