There were two elders living together in a cell, and they had never had so much as one quarrel with one another. One therefore said to the other: Come on, let us have at least one quarrel, like other men. The other said: I don’t know how to start a quarrel. The first said: I will take this brick and place it here between us. Then I will say: It is mine. After that you will say: It is mine. This is what leads to a dispute and a fight. So then they placed the brick between them, one said: It is mine, and the otehr replied to the first: I do believe that it is mine. The first one said again: It is not yours, it is mine. So the other answered: Well then, if it is yours, take it! Thus they did not manage after all to get into a quarrel.
Thomas Merton The Wisdom of the Desert: Some Sayings of the Desert Fathers
(New York, New Directions, 1960: p 67)