To thrive on this finite planet humans need to reduce material and energy consumption by over 80%, and do so, most likely, by mid-century. The need for such a radical change in our behavior derives from an expectation of diminishing and, eventually, leveling material and energy abundance, and an appreciation of the climate disruption caused by our consumption.
Such a transition will be historically unprecedented, but it need not be a collapse, nor a return to a distant past. It will involve giving up business-as-usual thinking and the misdirected hope that, given time, we can return to normal. It will require our adapting to a more appropriate pace. Transitioning to a sustainable patterns of living requires using a psychology of transitions. We must plan for, motivate, and maintain radical, yet perhaps delightful, behavior change starting with each of us, where we are, now.