How does Chapter 17 use the analogy of the swan to illustrate the choice between Shreya and Preya?

In Chapter 17, the analogy of the swan is used to demonstrate the power of discrimination in choosing the spiritual path. The text explains that just as milk and water can be mixed together, so are Shreya (the good) and Preya (the pleasant) blended in life. However, a swan, or 'Maral,' possesses the unique ability to drink only the pure milk from the mixture, leaving the water behind. In the same way, the chapter teaches that those who are courageous, intelligent, and wise can discern and cling only to Shreya, effectively separating it from the allure of Preya and always turning away from worldly temptations.