The Introduction begins by laying out the process of evolution and the importance of the brain’s role in it. Wiest states that humans would not be so advanced, empathetic, or successful without the parts of brain function that make humans depressed and anxious. The Introduction lays the groundwork for the book’s underlying message that ideas can change people’s lives.

Wiest argues that every culture accepts as truth certain things that are not actually objective. Once accepted as truth, humans are no longer capable of seeing it as cultural or subjective. The author argues that planning to be happy in a future that is inherently unpredictable makes it difficult to achieve happiness. What one ends up experiencing is something different, and maybe even better, but it is foreign and therefore perceived as emotionally “bad.” Wiest dispels what she considers misconceptions: that happiness is a place at which to arrive and that fear or pain are bad emotions. She states that people create unnecessary problems and barriers in their lives as an avoidance technique. Ultimately, to change one’s life, one must change beliefs and be willing to face problems. A person is not defined by their past since their past is not defined but ever-changing based on how a person views it.