There is nothing more powerful than the made-up mind.

When I was born, the world's population was 3.5 billion. There are now 6.8 billion people on the planet. By 2050, that's expected to rise to 9.4 billion. What's more, the Earth's resources aren't growing; they're decreasing - and rapidly.

The swim at Deception Island was by far the hardest swim I've ever done. Antarctica is a very unforgiving environment. If you don't train properly, you'll die.

The blues is also existential and offers a sense of mature reflection that enabled it to be the leitmotif of modern life.

I think that I was slightly naive. I thought that if I showed people the beauty of the Arctic and the beauty of the polar bears that they would care so much that they would stand up and try to make a change.

Of all the creatures in the world that really frighten me - the hyena in Africa, the great white shark - leopard seals are near the top of the list. They're killers. If my team spots one, they'll pull me out of the water.

If we pass on an unsustainable environment to our children we have failed them.