How does Chapter 17 contrast the choices made by a wise person versus a dull-witted person when faced with Shreya and Preya?

According to Chapter 17, the fundamental difference between a wise person and a dull-witted one lies in their ability to choose between Shreya (the good) and Preya (the pleasant). A wise, courageous, and intelligent individual is likened to a swan that can drink only the pure milk from a mixture of milk and water; similarly, they cling only to Shreya and turn away from Preya. In stark contrast, the chapter states that a dull-witted person, caught in the cycle of maintaining their body, family, and wealth, is conquered by Preya and embraces it. Even when both paths are available, this inherent lack of discrimination makes the right choice exceedingly difficult for them.