The core premise of the book is that your mind is divided into two parts: the Conscious Mind (the gatekeeper and reasoner) and the Subconscious Mind (the powerhouse and executor). Dr. Murphy argues that the subconscious mind does not argue; it simply accepts whatever the conscious mind believes to be true. By learning to "reprogram" this deeper part of the mind through techniques like visualization and affirmation, a person can change their health, wealth, and relationships.