One man watches a river flow by. If he does not wish it to flow, to change ceaselessly in accord with its nature, he will suffer great pain. Another man understands that nature of the river is to change constantly, regardless of his likes and dislikes, and therefore he does not suffer. To know existence as this flow, empty of lasting pleasure, void of self, is to find that which is stable and free of suffering, to find true peace in the world.