"No one prospers unless he renders benefit to others."
A good line, but free-market zealots parrot that no one enters a transaction unless they want to. But then we get monopolists and mafia in the garbage business and corrupt unions, because they know how to get someone else's buck so well- yet the victims benefit. So, how about:
"No one prospers unless she renders fair benefit to others."
You prosper most, when those around you prosper fairly by your actions. OR even better:
"One prospers most by providing more than fair benefits to others."