I've had the joy of spending thousands of hours under the sea. I wish I could take people along to see what I see, and to know what I know.

We are all together in this, we are all together in this single living ecosystem called Planet Earth. As we learn how we fit into the greater scheme of things, and begin to understand how the system works, we can plan ahead, we can use the resources responsibly, to show some respect for this inheritance that goes back 4.6 billion years.

Far and away, the greatest threat to the ocean, and thus to ourselves, is ignorance. But we can do something about that.

No creature on Earth ever has organized themselves in ways that we have, with the capacity to alter the nature of nature the way we have.

Success underwater depends mostly on how you conduct yourself. Diving can be the most relaxing experience in the world. Your weight seems to disappear. Space travel will be available only to a few individuals for some time, but the oceans are available to almost everyone - now.

Earth as an ecosystem stands out in the all of the universe. There's no place that we know about that can support life as we know it, not even our sister planet, Mars, where we might set up housekeeping someday, but at great effort and trouble we have to recreate the things we take for granted here.

Never again will we have this good a chance as we now have to find an enduring place for ourselves within the natural systems that keep us alive. It's a sweet spot in history. That's why this is such a critical time.