"For 50 years the environmental movement has unsuccessfully argued that we should save the planet for moral reasons, that there were more important things than money. Ironically, it now seems it will be money -- through the economic impact of climate change and resource constraint -- that will motivate the sweeping changes necessary to avert catastrophe.
The reason is we have now reached a moment where four words -- the earth is full -- will define our times. This is not a philosophical statement; this is just science based in physics, chemistry and biology. There are many science-based analyses of this, but they all draw the same conclusion -- that we're living beyond our means."