All my life I've been dogged by guilt because I feel there is this difference between the way I look and the way I feel inside.

As an artist I just can't think of a better life than the one I've been blessed with. It's just a great ride.

The meter is ticking [particularly in the face of climate change], so you've got to get to as much as you can as fast as you can. I grew up with 'This Land Is Our Land,' and public land doesn't belong to that administration or this one. We want our kids to grow up with real natural places, not just photos of them.

The way I deal with arthritis is to keep moving. As long as I can play hard tennis, as long as I can ski or ride a horse - all kinds of things can come your way. As long as you can, do it. People who retire die. My dad retired and died shortly after. Just keep moving.

We've poisoned the air, the water, and the land. In our passion to control nature, things have gone out of control. Progress from now on has to mean something different. We're running out of resources and we are running out of time.

I was raised in California during the Second World War and into the '50s and everything was fine, everything was great. The sun always shone, everybody looked healthy and wore ties and smoked in restaurants, and there were cars for everybody - except us, because I came from a lower class neighbourhood. But [in France] I realised there was a different point of view, so when I came back to America a year and a half later I was much more focused on my own country culturally and politically.

Now is not the time to repudiate environmental balance, but rather it is the time for all of us to work together - politician, advocate, rancher, scientist, and citizen. Only by doing this will the United States move forward and be a leader in environmental issues and ensure sustainability to our delicate ecosystem.