This is one of the first and more profound books produced by the whole of the New Thought movement. It inspired authors as Orison Swett Marden, William Walker Atkinson, Christian D.Larson and others, that inspired by "Master Mulford", continued in the search for the inner forces that are part of every single human being, and which, well used, can take us to success, prosperity and happiness. This collection includes all six volumes, each volume originally a book itself. You will find in it phrases, advice and wisdom that is the base for all modern writers. Mulford is the source of sources.