The quote from Hilary Mantel's "Learning to Talk" contrasts the concepts of duty and beauty. The "straight line of Duty" symbolizes the path that one must take to fulfill responsibilities and adhere to moral obligations. It suggests that following this straightforward path is essential for achieving clarity and purpose in life.

On the other hand, the "curved line of Beauty" represents the allure of aesthetic experiences and the more whimsical aspects of life. While beauty is appealing and perhaps more enjoyable, it may divert one from the seriousness of duty. Thus, the quote emphasizes the importance of balancing the pursuit of duty and beauty, encouraging individuals to prioritize their responsibilities while also recognizing the charm that life's curves provide.