A philosopher asked his pupils to fill a vase until it overflowed. “Why does it spill?”
“Because it is full,” they said.
“No,” he replied. “It spills because it cannot hold more. Life is like this vase. Stuff it with anger, greed, fear, and the smallest nudge will spill you over.”
One pupil carried that image for life. People said he had the calm of a saint. His secret was simple: he had stopped filling his vase.