In 'The New Psychology' by Charles F. Haanel, the author of 'The Master Key System', you will learn how to unlock the power of positive thinking. Haanel believe that if you learn to think in a certain way than success can be yours. An important self-help book by one of the most important self help authors ever. Without Haanel we would never have had 'The Secret' or 'The Power of Positive Thinking'.