The power of your subconscious mind by Joseph Murphy, this book is really a great and very popular book currently I am reading on. I feel very positive whenever I read this book. This book is about the beliefs and notions that case an influence on our subconscious minds.
Other popular books written by Dr. Murphy that include The Miracle of Mind Dynamics, Your Infinite Power to Be Rich, The Amazing Laws of Cosmic Mind and Secrets of the I-Ching.