Thomas Midgley Jr. Invented leaded fuel and CFCs. Norman Borlaug developed semi-dwarf, high-yield, disease-resistant wheat varieties credited with saving over

Thomas Midgley Jr. Invented leaded fuel and CFCs. Norman Borlaug developed semi-dwarf, high-yield, disease-resistant wheat varieties credited with saving over a billion people from starvation. Ignaz Semmelweis discovered that it's a good idea to wash your hands before carrying out surgery.