Can you summarize the key teachings of Chapter 17 from the Sai Satcharitra regarding the paths of Shreya and Preya?

Chapter 17 of the Sai Satcharitra provides a detailed discourse on the two distinct paths available to humans: Shreya, the path of salvation and wisdom, and Preya, the path of worldly pleasure and ignorance. The chapter uses the analogy of a swan separating milk from water to illustrate how a wise and courageous person chooses Shreya, while a 'dull-witted' individual gets caught up in Preya due to attachments to wealth, status, and sensory gratification. The text asserts that the true purpose of human life is to discard Preya and embrace Shreya. This requires overcoming obstacles like ignorance (Maya), cravings, lust, and anger.