The Master Key to Riches - A Sequel to Think and Grow RichA Lifetime of Study Condensed and Clarified In 1908, Andrew Carnegie challenged Hill to discover and publish the practical Philosophy of Achievement that Carnegie knew existed, but had never been assembled. Published in 1928, Law of Success distilled Hill's interviews with over 500 "movers and shakers" of his day into a 16 volume course that became an overnight bestseller. It was published almost exactly 20 years after that Carnegie interview. In