“If Earth is considered a closed system, there will be less for all forever. The frontier is closed, the wilderness is gone, nature is being destroyed by human consumers, while billions are starving. The future indeed looks grim, and there are, ultimately, no really long-range, positive solutions, nor motivation for making the sacrifices and doing the hard work needed now, unless we understand that we are evolving from an Earth-only toward an Earth-space or universal species.”

“Of all the generations of humans that have walked the surface of the Earth — for 100,000 years, going back when we first left Africa — the generation now alive is the most important.

The generation now alive, the generation that you see, looking around you, for the first time in history, is the generation that controls the destiny of the planet itself.”