I like the evening in India, the one magic moment when the sun balances on the rim of the world, and the hush descends, and ten thousand civil servants drift homeward on a river of bicycles, brooding on the Lord Krishna and the cost of living.

So my message is in whichever realm, be it going into space or going into the deep sea, you have to balance the yin and yang of caution and boldness, risk aversion and risk taking, fear and fearlessness. No great accomplishment takes place, whether it be a movie or a deep ocean expedition, or a space mission, without a kind of dynamic equipoise between the two. Luck is not a factor. Hope is not a strategy. Fear is not an option.

With 'Avatar,' I thought, Forget all these chick flicks and do a classic guys' adventure movie, something in the Edgar Rice Burroughs mold, like John Carter of Mars - a soldier goes to Mars.

I've tried not to get sucked into the Hollywood hierarchy system. Personally, I don't like it when people are deferential to me because I'm an established filmmaker. It's a blue-collar sensibility.

Every time you dive, you hope you'll see something new - some new species. Sometimes the ocean gives you a gift, sometimes it doesn't.

Climate change is critical to me because I'm a parent; I feel a sense of responsibility to the future. I'm not going to be around to see its worst effects, which are going to be hitting in the 2030s, '40s, '50s, but my kids will.

The film industry is about saying 'no' to people, and inherently you cannot take 'no' for an answer.