"Overconsumption is the engine of war. It forces nations to intervene with other nations, to compete with other nations, to exploit other nations. You cannot simply blame political leaders or political theories when people’s way of life itself is generating the need for this exploitation." 
"People who are living in the wealthy nations are encouraged to spend and to consume, to expand their lives, to own more things, to have more obligations, but in reality they cannot really afford this. And so they become overextended, and then life presents unanticipated events—illnesses, other problems, expenses that were unforeseen."
"Overconsumption, of course, has an impact on the world. When it is undertaken by a whole nation of people, it becomes the engine of war. It drives nations to intervene in other nations, to try to control other nations to gain access to their resources. It engenders deception and unethical behavior and ultimately war itself, as the appetites of a whole nation now drive it to struggle and to fight with other nations over who will have access to the resources of those other nations. You may say, “Well, I’m just one person. I don’t consume much. What difference does it make? It does not make a difference.” But to Knowledge within you which is wholly honest and wholly ethical it does make a difference. And to how you feel about yourself and your behavior and your value, it does make a difference. Perhaps it is slight. But as these slights repeat themselves they grow in scope and they erode your self confidence. They erode your self evaluation and your self esteem." 
"You must realize that you must live simply, that you must use resources very conscientiously, that the preservation of resources is not simply a focus for nations and governments, but for each individual." 
"Live simply. Own only the minimum of what you need. Relieve yourself of unnecessary possessions. Focus your work on essential goods and services. Support your local commerce, and learn to get around without the use of an automobile to the greatest extent possible." 
"Those people who are choosing to live differently in the wealthy nations, they are promoting real change by demonstration. Those people who are taking care of the poor and depressed and deprived peoples of the world, they are promoting real change. Those people who are consuming less of the world, as a matter of moral and ethical principle, they are promoting real change. Those people who are committing themselves to what humanity will need in the future and not simply to the fashions and fantasies of humanity, they are part of real change." 
2008 financial crisis
"Do not think that when you get through this crisis, it will all be fine again, and humanity can continue its overconsumption of the world, like locusts upon the land, consuming everything in sight, degrading the very world that sustains you and that gives you life."