As long as there is a lack of the inner discipline that brings calmness of mind, no matter what external facilities or conditions you have, they will never give you the feeling of joy and happiness that you are seeking. On the other hand, if you possess this inner quality, a calmness of mind, a degree of stability within, then even if you lack various external facilities that you would normally consider necessary for happiness, it is still possible to live a happy and joyful life.

— Dalai Lama

from The Art of Happiness