According to Chapter 8, what is the 'true duty' of human life, and how does it contrast with a life of mere existence?

Chapter 8 of the Sai Satcharitra presents a profound philosophy on human existence. It argues that if life is wasted solely on the four activities of eating, sleeping, fear, and mating, there is no meaningful difference between a human and a dog. The text explicitly states that the true duty of human birth is the attainment of the Supreme Self (Paramatman). As explained in Chapter 8, a life dedicated only to nourishing the body and seeking sensual pleasure is considered useless. The chapter challenges the reader to use wisdom and recognize that the potential for self-realization is what makes human birth truly great, unlike the mere survival instincts shared with dogs and pigs.