How does Chapter 8 describe the physical human body and its ever-changing nature?

In Chapter 8, the human body is depicted as being in a constant state of flux, despite appearing singular and constant. The text uses the analogy of a lamp's flame, which looks the same from beginning to end but is actually different every moment. Similarly, the stages of life like childhood, youth, and old age come and go without anyone noticing the exact transition. What is seen one moment perishes in the next. Furthermore, the chapter provides a stark description of the body as a 'washroom of excrement and urine' and a 'foul place of phlegm, pus, and saliva,' emphasizing its impurity and the ever-present reality of death at every moment.