Although my own experience may be very little, one thing that I can say for certain is that I feel that through Buddhist training, I feel that my mind has become much more calm. That's definite. Although the change has come about gradually, perhaps centimeter by centimeter," he laughed, "I think that there has been a change in my attitude towards myself and others. Although it's difficult to point to the precise causes of this change, I think that it has been influenced by a realization, not full realization, but a certain feeling or sense of the underlying fundamental nature of reality, and also through contemplating subjects such as impermanence, our suffering nature, and the value of compassion and altruism.

— Dalai Lama

from The Art of Happiness