A short, bitter parable preserved as Gaster's exemplum No. 210 teaches the kind of lesson a Jew is meant to carry with him into the street.
A man was clearing his field of stones. Rather than haul them to a pile on his own land, he threw them one by one onto the public road so that he would not have to store them. A chasid, a pious man, passing by, saw what he was doing and rebuked him.
"Friend, this makes no sense. You are taking stones from a place that does not really belong to you and throwing them into a place that does."
The worker laughed. "What are you talking about? This field is mine. The road belongs to no one."
The pious man said no more and walked on.
Years passed. The man fell on hard times and was forced to sell the field. One afternoon he found himself walking along that same public road he had once pelted with stones. And in the dusk his foot caught. He stumbled. Again. Again. He cursed the unseen obstructions, and when he bent to examine them, he recognized the very stones he had thrown there years before.
The field that had seemed permanently his was no longer his. But the road — the public road, the one he had thought belonged to no one — still belonged to him, because he still had to walk it.
The rabbis teach from this parable a principle that runs through all of Jewish ethics. Reshut ha-rabim, the public domain, is no one's property and everyone's property. What you toss into the common road, sooner or later, you will trip over yourself. Private fortunes change; the road keeps every stone.