The stone and the clam

A stone passed a century at the bottom of a riverbed, at rest while the world whipped by through the water flowing overhead.

One day, a clam lodged itself up against the stone, where it could take a break from the endless toil of feeding itself and hiding from predators. The clam then commented, “Thank you stone, for letting me settle away from the constant pull of the river's current, I was in need of a break.”

“You are most welcome, do stay as long as you like” rejoined the stone.

Soon, however, the clam grew hungry once more, and set out to make its way downstream. Before it left, it spoke “Stone, you and I are much alike. We are hard, smooth, and rounded, and we spend our days in the river's bed. But, how do you manage to stay put for so long. I've been here only a short while, and now feel the need to be off again.”

“First,” recounted the stone, “you were tired, and so you rested. And then your hunger made you restless to be on the move again. This should give you your answer.”

Only a stone is without need.