Can you summarize the core message of Chapter 17 regarding the paths of Shreya and Preya?

Chapter 17 of the Shri Sai Satcharitra explains the two distinct paths available to humans: Shreya, the path of salvation and good, and Preya, the path of worldly joy and pleasure. The chapter describes these two as being as opposite as light and darkness. It teaches that Shreya is the form of wisdom (Vidya), while Preya is the form of ignorance (Avidya). A person whose mind gravitates towards Preya, driven by worldly attachments, ultimately falls away from their true self-interest. In contrast, as the text illustrates, the wise and fortunate choose Shreya, which is the true purpose of human life. The chapter uses the analogy of a swan separating milk from water to describe how the wise discern and choose the good path.