What is the philosophical argument in Chapter 8 regarding the transient nature of life and the body?

In Chapter 8, the text emphasizes the fleeting and constantly changing nature of both life and the physical body. It uses the analogy of a lamp's flame, which appears constant but is different every moment, to illustrate the state of the body. The chapter notes that childhood, youth, and old age are distinct phases, yet the transition between them goes unnoticed. It states, 'What is seen one moment perishes the next,' highlighting the impermanence of our physical form, which is described as being as transient as a peepal leaf. This philosophical view, as detailed in Chapter 8, serves as a powerful reminder of life's brevity and the urgency of pursuing the true purpose of human birth, which is self-realization.