Ending Greed Within

In Tea Words Volume II, Master Sheng Yen explores the ways in which what appear to be "external" problems that are "out there" are actually manifestations of internal states of being. Whenever people fight to save the planet, for example, they must ask the question, do the problems in life come from "outside", in some external condition, or do they really come from deep within? I have found in my own life, it's greed for some kind of mental or physical comfort that often causes a lot of mental problems and hardships.
   Master Sheng Yen remarks:

...we must each try to have less greed, hatred, ignorance, arrogance, and doubt in our minds. This will naturally lead the world in a better direction. It will become a purer, healthier, and safer place in which to live. How do we achieve this goal? We must depend on the teachings, concepts, and methods of practice of Buddhadharma. Only with these can we reach the goal of purity of mind. Only when the mind is pure can the external environment become pure. Only when you attain purity of mind can you see the purity of the external world. Without this inner peace and purity, the world will always be troubled by problems (p.24)

When we look at this paragraph, we might reflect, how do internal states of being relate to the state of the world? One obvious way is that through wanting many things, people contribute to overproduction and consumption. It's only when I am consuming "just enough" and have the attitude that "enough is enough" that I allow life to naturally take its course without trying to accumulate too much.
  Another point is that when a person is less greedy for things, they are more available for others, which can lessen loneliness in the world. A person with two empty hands has much more to give than one with two full, clenched fists. When I am too absorbed in holding onto something, even an ideal or a dream, I end up losing the gift of the present moment. I am also unable to provide the greatest gift that I can offer anyone, namely, my undivided attention and presence.
 
Sheng Yen (2013) Tea Words Volume II. Elmhurst NY: Dharma Drum Publications