Unrestrained automobility, hedonism, individualism, and conspicuous consumption cannot be sustained because they take more than they give back. A spiritually impoverished world cannot be sustained because meaninglessness, anomie, and despair will corrode the desire to be sustained and the belief that humanity is worth sustaining. But these are the very things that distinguish the modern age from its predecessors. Genuine sustainability, in other words, will come not from superficial changes but from a deeper process akin to humankind growing up to a fuller stature.
- David W. Orr