In the introduction, the author, Dr. Joe Dispenza, defines “placebo” as a harmless, non-active treatment, like a sugar pill or saline injection, which benefits its recipient because they expect a benefit. Placebo, the Latin word for “I will please,” is the medical term for a harmless, neutral treatment used as a control to prove the benefit of a new medication or treatment during trial, study, or experimentation. These fake treatments sometimes induce real, positive change—a phenomenon known as the placebo effect—suggesting that the expectation of improvement is sometimes enough to trigger physical healing. The author posits that individuals can deliberately trigger this effect in themselves, effectively becoming the placebo and enacting positive change simply by believing in their ability to do so. The introduction then warns that this book will not contain any discussion of the ethics of placebo treatment in medical trials or a discussion of “various healing modalities” (xxxi) both medically proven and/or holistic, and instead will address what the author considers to be the most intriguing modality: healing through thought alone.

The introduction then provides a brief overview of the contents of the book. Part 1, Chapters 1-10, comprises all the details and background information required to understand the placebo effect and how it can work.