Buck discusses the concept of stoicism and its application in modern life. Stoicism is a timeless philosophy that teaches us to master our emotions, focus on what matters, and thrive in the chaos of modern life. The key idea in stoicism is that we have power over our minds, not outside events. We can control our actions, thoughts, and responses, but we cannot control external circumstances. Stoicism teaches us to focus our energy on what we can control and let go of everything else. It also emphasizes the importance of perceiving events in a way that empowers us and leads to growth. The Stoics believed in living in accordance with virtue, which includes wisdom, courage, justice, and discipline. They also emphasized the concept of memento mori, reminding us of our mortality and the importance of living with purpose and urgency.