This chapter is a continuation of the previous two chapters. The first chapter, free travel, tells us how to get rid of the material world. The second chapter, the theory of the homology of all things, tells us what is the real "Tao body" and what is the real origin of all things. The third chapter is that the "master of health preservation" naturally falls on people, and what is the biggest problem for people-life and death. The whole chapter tells us how to live and die. First of all, we must understand that the life and death of our bodies is only a natural phenomenon, so we can treat our life calmly and objectively. First of all, be cautious in life even if it is extraordinary, because greatness often returns to ordinary in the end. Then tell us to the teacher that appearance is only a superficial phenomenon, and people should have detached and independent personality, so that detached personality will transcend the limitations of the body and give full play to people's greatest potential. Finally, through the death of Lao Dan, the central idea is highlighted: the salary is exhausted. Death is no big deal. What we are really afraid of is not death, but not knowing where to go after death. So as long as you believe that spiritual life is always bright, you will not be afraid of death. And being able to find this truth that can make us live and die, and continue our brilliant life, this truth is "Tao", and knowing where the real "Tao" is is the real health care.