I visited an ad hoc elementary school in Surakarta that used an old semi, a shipping container, a bus and train car as class rooms. The children had adorned every inch of them, painting murals and plastering them with homework assignments and art projects. The entire school was off every grid and built from virtually 100% recycled content. It made me think how silly it would be to even attempt LEED certification for a place like this. USGBC hasn't conceived of a rating high enough to encapsulate the social, environmental and economic innovation of this place. And so began a clearer sense for me of what true sustainability might be.
This might lead us to see sustainability as the continuing survival of the human race through preservation of the environment. Wandering through that tiny school, though, made me believe sustainability is not purely biological, but rather the capacity for the human race to preserve humanity.