Most people think that slapping other parts of the body is safer while slapping the head is more dangerous. Some people even think that slapping the head can make people stupid. However, many clinical trials have proven that the opposite is true. Slapping the head is safer than slapping other parts of the body because the skull protects the brain, and the more you slap the head, the smarter you become, especially for the elderly and children. Regarding head diseases, headaches are the most common, followed by diseases of the mouth, teeth, ears, nose, eyes, and other head organs. For middle-aged and elderly people, diseases related to the brain and nerves increase with age. For the convenience of inquiry and discussion, I classified the diseases of the mouth, ears, nose, and eyes into independent reports, and included brain nerve diseases in the neurodegenerative disease list as another report. However, headaches are related to all the above diseases. Western medicine connects them with anatomy and the nervous system, while traditional Chinese medicine focuses on the relationship between them through meridians. The PL method further simplifies the theory of traditional Chinese medicine, replacing meridians and acupoints with parts, making clinical operations easier to popularize among the public. So, both traditional Chinese medicine and Western medicine have been simplified.