The first responsibility of a professional

The first responsibility of a professional was spelled out clearly, twenty-five hundred years ago, in the Hippocratic oath of the Greek physician: Primum non nocere-"Above all, not knowingly to do harm." (...) (This) is the basic rule of professional ethics, the basic rule of an ethics of public responsibility. (...)

The Essential Drucer
Peter F. Drucker
Collins Business (HarperCollins)