Punishment may make us obey the orders we are given, but at best it will only teach an obedience to authority, not a self-control which enhances our self-respect.
Bio: George David Wald was an American scientist who was best known for his work with pigments in the retina. He won a share of the 1967 Nobel Prize in Physiology or Medicine with Haldan Keffer Hartline and Ragnar Granit.