With earth's burgeoning human population to feed we must turn to the sea with understanding and new technology. We need to farm it as we farm the land.

We must alert and organise the world's people to pressure world leaders to take specific steps to solve the two root causes of our environmental crises - exploding population growth and wasteful consumption of irreplaceable resources. Overconsumption and overpopulation underlie every environmental problem we face today.

The real cure for our environmental problems is to understand that our job is to salvage Mother Nature. We are facing a formidable enemy in this field. It is the hunters... and to convince them to leave their guns on the wall is going to be very difficult.

Through the window of my mask I see a wall of coral, its surface a living kaleidoscope of lilac flecks, splashes of gold, reddish streaks and yellows, all tinged by the familiar transparent blue of the sea.

We have to prepare for what life could become in 40 years. We need to outline what is possible and what is impossible with the non-renewable resources of the Earth. What role will technological improvement play? Taking all this into account, what kind of life can we produce in the best way for 10 billion people? That's a problem that needs to be solved.

I experimented with all possible maneuvers-loops, somersaults and barrel rolls. I stood upside down on one finger and burst out laughing, a shrill, distorted laugh. Nothing I did altered the automatic rhythm of the air. Delivered from gravity and buoyancy, I flew around in space.

What is a scientist after all? It is a curious man looking through a keyhole, the keyhole of nature, trying to know what's going on.